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We consume energy in dozens of forms. Yet virtually all of the energy we use originates in the power of the atom. Nuclear fusion reactions energize stars, including the Sun, and the resulting sunlight has profound effects on our planet.

Sunlight contains a surprisingly large amount of energy. On average, even after passing through hundreds of kilometers of air on a clear day, solar radiation reaches Earth with enough energy in a single square meter to run a mid-size desktop computer—if all the sunlight could be captured and converted to electricity . Photovoltaic and solar thermal technologies harvest some of that energy now and will grow in both usage and efficiency in the future.

Solar radiation reaches Earth with enough energy in a single square meter to run a mid-size desktop computer.

The Sun’s energy warms the planet’s surface, powering titanic transfers of heat and pressure in weather patterns and ocean currents. The resulting air currents drive wind turbines. Solar energy also evaporates water that falls as rain and builds up behind dams, where its motion is used to generate electricity via hydropower .

Most Americans, however, use solar energy in its secondhand form: fossil fuels . When sunlight strikes a plant, some of the energy is trapped through photosynthesis and is stored in chemical bonds as the plant grows. Of course we can recover that energy directly months or years later by burning plant products such as wood, which breaks the bonds and releases energy as heat and light. More often, though, we use the stored energy in the much more concentrated forms that result when organic matter, after millions of years of geological and chemical activity underground, turns into coal , oil , or natural gas . Either way, we’re reclaiming the power of sunlight.

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December 14, 2015

How does the sun produce energy?

by Fraser Cain, Universe Today

There is a reason life that Earth is the only place in the solar system where life is known to be able to live and thrive. Granted, scientists believe that there may be microbial or even aquatic life forms living beneath the icy surfaces of Europa and Enceladus, or in the methane lakes on Titan. But for the time being, Earth remains the only place that we know of that has all the right conditions for life to exist.

One of the reasons for this is because the Earth lies within our sun 's Habitable Zone (aka. "Goldilocks Zone"). This means that it is in right spot (neither too close nor too far) to receive the sun's abundant energy , which includes the light and heat that is essential for chemical reactions . But how exactly does our sun go about producing this energy? What steps are involved, and how does it get to us here on planet Earth?

The simple answer is that the sun, like all stars, is able to create energy because it is essentially a massive fusion reaction. Scientists believe that this began when a huge cloud of gas and particles (i.e. a nebula) collapsed under the force of its own gravity – which is known as Nebula Theory. This not only created the big ball of light at the center of our solar system, it also triggered a process whereby hydrogen, collected in the center, began fusing to create solar energy .

Technically known as nuclear fusion, this process releases an incredible amount of energy in the form of light and heat. But getting that energy from the center of our sun all the way out to planet Earth and beyond involves a couple of crucial steps. In the end, it all comes down to the sun's layers, and the role each of them plays in making sure that solar energy gets to where it can help create and sustain life.

The core of the sun is the region that extends from the center to about 20–25% of the solar radius. It is here, in the core, where energy is produced by hydrogen atoms (H) being converted into nuclei of helium (He). This is possible thanks to the extreme pressure and temperature that exists within the core, which are estimated to be the equivalent of 250 billion atmospheres (25.33 trillion KPa) and 15.7 million kelvin, respectively.

The net result is the fusion of four protons (hydrogen nuclei) into one alpha particle – two protons and two neutrons bound together into a particle that is identical to a helium nucleus. Two positrons are released from this process, as well as two neutrinos (which changes two of the protons into neutrons), and energy.

The core is the only part of the sun that produces an appreciable amount of heat through fusion. In fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius. By 30% of the radius, fusion has stopped almost entirely. The rest of the sun is heated by the energy that is transferred from the core through the successive layers, eventually reaching the solar photosphere and escaping into space as sunlight or the kinetic energy of particles.

The sun releases energy at a mass–energy conversion rate of 4.26 million metric tons per second, which produces the equivalent of 384.6 septillion watts (3.846×10 26 W). To put that in perspective, this is the equivalent of about 9.192×10 10 megatons of TNT per second, or 1,820,000,000 Tsar Bombas – the most powerful thermonuclear bomb ever built!

Radiative Zone:

This is the zone immediately next to the core, which extends out to about 0.7 solar radii. There is no thermal convection in this layer, but solar material in this layer is hot and dense enough that thermal radiation is all that is needed to transfer the intense heat generated in the core outward. Basically, this involves ions of hydrogen and helium emitting photons that travel a short distance before being reabsorbed by other ions.

Temperatures drop in this layer, going from approximately 7 million kelvin closer to the core to 2 million at the boundary with the convective zone. Density also drops in this layer a hundredfold from 0.25 solar radii to the top of the radiative zone, going from 20 g/cm 3 closest to the core to just 0.2 g/cm 3 at the upper boundary.

Convective Zone:

This is the sun's outer layer, which accounts for everything beyond 70% of the inner solar radius (or from the surface to approx. 200,000 km below). Here, the temperature is lower than in the radiative zone and heavier atoms are not fully ionized. As a result, radiative heat transport is less effective, and the density of the plasma is low enough to allow convective currents to develop.

Because of this, rising thermal cells carry the majority of the heat outward to the sun's photosphere. Once these cells rise to just below the photospheric surface, their material cools, causing their density increases. This forces them to sink to the base of the convection zone again – where they pick up more heat and the convective cycle continues.

At the surface of the sun, the temperature drops to about 5,700 K. The turbulent convection of this layer of the sun is also what causes an effect that produces magnetic north and south poles all over the surface of the sun.

It is also on this layer that sunspots occur, which appear as dark patches compared to the surrounding region. These spots correspond to concentrations in the magnetic flux field that inhibit convection and cause regions on the surface to drop in temperature to compared to the surrounding material.

Photosphere:

Lastly, there is the photosphere, the visible surface of the sun. It is here that the sunlight and heat that are radiated and convected to the surface propagate out into space. Temperatures in the layer range between 4,500 and 6,000 K (4,230 – 5,730 °C; 7646 – 10346 °F). Because the upper part of the photosphere is cooler than the lower part, an image of the sun appears brighter in the center than on the edge or limb of the solar disk, in a phenomenon known as limb darkening.

The photosphere is tens to hundreds of kilometers thick, and is also the region of the sun where it becomes opaque to visible light. The reasons for this is because of the decreasing amount of negatively charged Hydrogen ions (H–), which absorb visible light easily. Conversely, the visible light we see is produced as electrons react with hydrogen atoms to produce H– ions.

The energy emitted from the photosphere then propagates through space and reaches Earth's atmosphere and the other planets of the solar system. Here on Earth, the upper layer of the atmosphere (the ozone layer) filters much of the sun's ultra-violet (UV) radiation, but passes some onto the surface. The energy that received is then absorbed by the Earth's air and crust, heating our planet and providing organisms with a source of energy.

The sun is at the center of biological and chemical processes here on Earth. Without it, the life cycle of plants and animals would end, the circadian rhythms of all terrestrial creatures would be disrupted; and in time, all life on Earth would cease to exist. The sun's importance has been recognized since prehistoric times, with many cultures viewing it as a deity (more often than not, as the chief deity in their pantheons).

But it is only in the past few centuries that the processes that power the sun have come to be understood. Thanks to ongoing research by physicists, astronomers and biologists, we are now able to grasp how the sun goes about producing energy, and how it passes that on to our solar system. The study of the known universe, with its diversity of star systems and exoplanets – has also helped us to draw comparisons with other types of stars.

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The sun is an ordinary star, one of about 100 billion in our galaxy, the Milky Way. The sun has extremely important influences on our planet: It drives weather, ocean currents, seasons, and climate, and makes plant life possible through photosynthesis.

Biology, Earth Science, Astronomy, Physics

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The sun is an ordinary  star , one of about 100 billion in our galaxy , the Milky Way. The sun has extremely important influences on our planet: It drives weather, ocean currents, seasons, and  climate , and makes plant life possible through  photosynthesis . Without the sun’s heat and light, life on Earth would not exist. About 4.5 billion years ago, the sun began to take shape from a  molecular cloud  that was mainly composed of hydrogen and helium. A nearby  supernova  emitted a shockwave, which came in contact with the molecular cloud and energized it. The molecular cloud began to  compress , and some regions of gas collapsed under their own  gravitational pull . As one of these regions collapsed, it also began to  rotate  and heat up from increasing pressure. Much of the hydrogen and helium remained in the center of this hot, rotating mass. Eventually, the gases heated up enough to begin  nuclear fusion , and became the sun in our  solar system . Other parts of the molecular cloud cooled into a disc around the brand-new sun and became planets, asteroids, comets, and other bodies in our solar system. The sun is about 150 million kilometers (93 million miles) from Earth. This distance, called an  astronomical unit  (AU), is a standard measure of distance for  astronomers and astrophysicists. An AU can be measured at light speed, or the time it takes for a photon of light to travel from the sun to Earth. It takes light about eight minutes and 19 seconds to reach Earth from the sun. The  radius  of the sun, or the distance from the very center to the outer limits, is about 700,000 kilometers (432,000 miles). That distance is about 109 times the size of Earth’s radius. The sun not only has a much larger radius than Earth—it is also much more massive. The sun’s mass is more than 333,000 times that of Earth, and contains about 99.8 percent of all of the mass in the entire solar system! Composition The sun is made up of a blazing combination of gases. These gases are actually in the form of plasma . Plasma is a state of matter similar to gas, but with most of the particles  ionized . This means the particles have an increased or reduced number of electrons. About three quarters of the sun is hydrogen, which is constantly fusing together and creating helium by a process called nuclear fusion. Helium makes up almost the entire remaining quarter. A very small percentage (1.69 percent) of the sun’s mass is made up of other gases and metals: iron, nickel, oxygen, silicon, sulfur, magnesium, carbon, neon, calcium, and chromium This 1.69 percent may seem insignificant, but its mass is still 5,628 times the mass of Earth. The sun is not a solid mass. It does not have the easily identifiable boundaries of rocky planets like Earth. Instead, the sun is composed of layers made up almost entirely of hydrogen and helium. These gases carry out different functions in each layer, and the sun’s layers are measured by their percentage of the sun’s total radius. The sun is permeated and somewhat controlled by a  magnetic field . The magnetic field is defined by a combination of three complex mechanisms: a circular electric current that runs through the sun, layers of the sun that rotate at different speeds, and the sun’s ability to conduct  electricity . Near the sun’s  equator , magnetic field lines make small loops near the surface. Magnetic field lines that flow through the poles extend much farther, thousands of kilometers, before returning to the opposite pole. The sun rotates around its own axis, just like Earth. The sun rotates counterclockwise, and takes between 25 and 35 days to complete a single rotation. The sun  orbits clockwise around the center of the Milky Way. Its orbit is between 24,000 and 26,000 light-years away from the galactic center. The sun takes about 225 million to 250 million years to orbit one time around the galactic center. Electromagnetic Radiation The sun’s energy travels to Earth at the speed of light in the form of electromagnetic radiation (EMR). The  electromagnetic spectrum  exists as waves of different frequencies and  wavelengths . The  frequency  of a wave represents how many times the wave repeats itself in a certain unit of time. Waves with very short wavelengths repeat themselves several times in a given unit of time, so they are high-frequency. In contrast, low-frequency waves have much longer wavelengths. The vast majority of electromagnetic waves that come from the sun are invisible to us. The most high-frequency waves emitted by the sun are gamma rays, x-rays, and  ultraviolet radiation  (UV rays). The most harmful UV rays are almost completely absorbed by Earth’s atmosphere. Less potent UV rays travel through the atmosphere, and can cause sunburn. The sun also emits  infrared radiation —whose waves are a much lower-frequency. Most heat from the sun arrives as infrared energy. Sandwiched between infrared and UV is the visible spectrum, which contains all the colors we, as humans, can see. The color red has the longest wavelengths (closest to infrared), and violet (closest to UV) the shortest. The sun itself is white, which means it contains all the colors in the visible spectrum. The sun appears orangish-yellow because the blue light it emits has a shorter wavelength, and is scattered in the atmosphere—the same process that makes the sky appear blue. Astronomers, however, call the sun a “yellow dwarf” star because its colors fall within the yellow-green section of the electromagnetic spectrum. Evolution of the Sun The sun, although it has sustained all life on our planet, will not shine forever. The sun has already existed for about 4.5 billion years. The process of nuclear fusion, which creates the heat and light that make life on our planet possible, is also the process that slowly changes the sun’s composition. Through nuclear fusion, the sun is constantly using up the hydrogen in its core : Every second, the sun fuses around 620 million metric tons of hydrogen into helium. At this stage in the sun’s life, its core is about 74 percent hydrogen. Over the next five billion years, the sun will burn through most of its hydrogen, and helium will become its major source of fuel. Over those five billion years, the sun will go from “yellow dwarf” to “ red giant .” When almost all of the hydrogen in the sun’s core has been consumed, the core will contract and heat up, increasing the amount of nuclear fusion that takes place. The outer layers of the sun will expand from this extra energy. The sun will expand to about 200 times its current radius, swallowing Mercury and Venus. Astrophysicists debate whether Earth’s orbit would expand beyond the sun’s reach, or if our planet would be engulfed by the sun as well. As the sun expands, it will spread its energy over a larger surface area, which has an overall cooling effect on the star. This cooling will shift the sun’s visible light to a reddish color—a red giant. Eventually, the sun’s core reaches a temperature of about 100 million on the  Kelvin scale (almost 100 million degrees Celsius or 180 million degrees Farenheit), the common scientific scale for measuring temperature. When it reaches this temperature, helium will begin fusing to create carbon, a much heavier element. This will cause intense solar wind and other solar activity, which will eventually throw off the entire outer layers of the sun. The red giant phase will be over. Only the sun’s carbon core will be left, and as a “ white dwarf ,” it will not create or emit energy. Sun’s Structure The sun is made up of six layers: core, radiative zone , convective zone, photosphere , chromosphere , and corona . Core The sun’s  core , more than a thousand times the size of Earth and more than 10 times  denser than lead, is a huge furnace. Temperatures in the core exceed 15.7 million kelvin (also 15.7 million degrees Celsius, or 28 million degrees Fahrenheit). The core extends to about 25 percent of the sun’s radius. The core is the only place where nuclear fusion reactions can happen. The sun’s other layers are heated from the nuclear energy created there. Protons of hydrogen atoms violently collide and fuse, or join together, to create a helium atom. This process, known as a PP (proton-proton) chain reaction, emits an enormous amount of energy. The energy released during one second of solar fusion is far greater than that released in the explosion of hundreds of thousands of hydrogen bombs. During nuclear fusion in the core, two types of energy are released: photons and neutrinos . These particles carry and emit the light, heat, and energy of the sun. Photons are the smallest particle of light and other forms of electromagnetic radiation. Neutrinos are more difficult to detect, and only account for about two percent of the sun’s total energy. The sun emits both photons and neutrinos in all directions, all the time. Radiative Zone The radiative zone of the sun starts at about 25 percent of the radius, and extends to about 70 percent of the radius. In this broad zone, heat from the core cools dramatically, from between seven million K (12 million°F or 7 million°C) to two million K (2 million°C or 4 million°F). In the radiative zone, energy is transferred by a process called thermal radiation. During this process, photons that were released in the core travel a short distance, are absorbed by a nearby ion, released by that ion, and absorbed again by another. One photon can continue this process for almost 200,000 years! Transition Zone : Tachocline Between the radiative zone and the next layer, the convective zone, there is a transition zone called the tachocline. This region is created as a result of the sun’s differential rotation . Differential rotation happens when different parts of an object rotate at different velocities. The sun is made up of gases undergoing different processes at different layers and different latitudes. The sun’s equator rotates much faster than its poles, for instance. The rotation rate of the sun changes rapidly in the tachocline. Convective Zone At around 70 percent of the sun’s radius, the convective zone begins. In this zone, the sun’s temperature is not hot enough to transfer energy by thermal radiation. Instead, it transfers heat by thermal  convection  through thermal columns. Similar to water boiling in a pot, or hot wax in a lava lamp, gases deep in the sun’s convective zone are heated and “boil” outward, away from the sun’s core, through thermal columns. When the gases reach the outer limits of the convective zone, they cool down, and plunge back to the base of the convective zone, to be heated again. Photosphere The photosphere is the bright yellow, visible "surface" of the sun. The photosphere is about 400 kilometers (250 miles) thick, and temperatures there reach about 6,000K (5,700°C, 10,300°F). The thermal columns of the convection zone are visible in the photosphere, bubbling like boiling oatmeal. Through powerful telescopes, the tops of the columns appear as  granules crowded across the sun. Each granule has a bright center, which is the hot gas rising through a thermal column. The granules’ dark edges are the cool gas descending back down the column to the bottom of the convective zone. Although the tops of the thermal columns look like small granules, they are usually more than 1,000 kilometers (621 miles) across. Most thermal columns exist for about eight to 20 minutes before they dissolve and form new columns. There are also “supergranules” that can be up to 30,000 kilometers (18,641 miles) across, and last for up to 24 hours. Sunspots , solar flares , and solar prominences take form in the photosphere, although they are the result of processes and disruptions in other layers of the sun. Photosphere: Sunspots A sunspot is just what it sounds like—a dark spot on the sun. A sunspot forms when intense magnetic activity in the convective zone  ruptures a thermal column. At the top of the ruptured column (visible in the photosphere), temperature is temporarily decreased because hot gases are not reaching it. Photosphere: Solar Flares The process of creating sunspots opens a connection between the corona (the very outer layer of the sun) and the sun’s interior. Solar matter surges out of this opening in formations called solar flares. These explosions are massive: In the period of a few minutes, solar flares release the equivalent of about 160 billion megatons of TNT, or about a sixth of the total energy the sun releases in one second. Clouds of ions, atoms, and electrons erupt from solar flares, and reach Earth in about two days. Solar flares and solar prominences contribute to  space weather , which can cause disturbances to Earth’s atmosphere and magnetic field, as well as disrupt satellite and telecommunications systems. Photosphere: Coronal Mass Ejections Coronal mass ejections (CMEs) are another type of solar activity caused by the constant movement and disturbances within the sun’s magnetic field. CMEs typically form near the active regions of sunspots, the correlation between the two has not been proven. The cause of CMEs is still being studied, and it is hypothesized that disruptions in either the photosphere or corona lead to these violent solar explosions. Photosphere: Solar Prominence Solar prominences are bright loops of solar matter. They can burst far into the coronal layer of the sun, expanding hundreds of kilometers per second. These curved and twisted features can reach hundreds of thousands of kilometers in height and width, and last anywhere from a few days to a few months. Solar prominences are cooler than the corona, and they appear as darker strands against the sun. For this reason, they are also known as filaments. Photosphere: Solar Cycle The sun does not constantly emit sunspots and solar ejecta; it goes through a cycle of about 11 years. During this solar cycle, the frequency of solar flares changes. During solar maximums, there can be several flares per day. During solar minimums, there may be fewer than one a week. The solar cycle is defined by the sun’s magnetic fields, which loop around the sun and connect at the two poles. Every 11 years, the magnetic fields reverse, causing a disruption that leads to solar activity and sunspots. The solar cycle can have effects on Earth’s climate. For example, the sun’s ultraviolet light splits oxygen in the stratosphere and strengthens Earth’s protective  ozone layer . During the solar minimum, there are low amounts of UV rays, which means that Earth’s ozone layer is temporarily thinned. This allows more UV rays to enter and heat Earth’s atmosphere. Solar Atmosphere The solar atmosphere is the hottest region of the sun. It is made up of the chromosphere, the corona, and a transition zone called the solar transition region that connects the two. The solar atmosphere is obscured by the bright light emitted by the photosphere, and it can rarely be seen without special instruments. Only during  solar eclipses , when the moon moves between Earth and the sun and hides the photosphere, can these layers be seen with the unaided eye. Chromosphere The pinkish-red chromosphere is about 2,000 kilometers (1,250 miles) thick and riddled with jets of hot gas. At the bottom of the chromosphere, where it meets the photosphere, the sun is at its coolest, at about 4,400K (4,100°C, 7,500°F). This low temperature gives the chromosphere its pink color. The temperature in the chromosphere increases with altitude, and reaches 25,000K (25,000°C, 45,000°F) at the outer edge of the region. The chromosphere gives off jets of burning gases called  spicules , similar to solar flares. These fiery wisps of gas reach out from the chromosphere like long, flaming fingers; they are usually about 500 kilometers (310 miles) in diameter. Spicules only last for about 15 minutes, but can reach thousands of kilometers in height before collapsing and dissolving. Solar Transition Region The solar transition region (STR) separates the chromosphere from the corona. Below the STR, the layers of the sun are controlled and stay separate because of gravity, gas pressure, and the different processes of exchanging energy. Above the STR, the motion and shape of the layers are much more dynamic. They are dominated by magnetic forces. These magnetic forces can put into action solar events such as coronal loops and the solar wind. The state of helium in these two regions has differences as well. Below the STR, helium is partially ionized. This means it has lost an electron, but still has one left. Around the STR, helium absorbs a bit more heat and loses its last electron. Its temperature soars to almost one million K (one million°C, 1.8 million°F). Corona The corona is the wispy outermost layer of the solar atmosphere, and can extend millions of kilometers into space. Gases in the corona burn at about one million K (one million°C, 1.8 million°F), and move about 145 kilometers (90 miles) per second. Some of the particles reach an  escape velocity  of 400 kilometers per second (249 miles per second). They escape the sun’s gravitational pull and become the solar wind. The solar wind blasts from the sun to the edge of the solar system. Other particles form coronal loops. Coronal loops are bursts of particles that curve back around to a nearby sunspot. Near the sun’s poles are coronal holes. These areas are colder and darker than other regions of the sun, and allow some of the fastest-moving parts of the solar wind to pass through. Solar Wind The solar wind is a stream of extremely hot, charged particles that are thrown out from the upper atmosphere of the sun. This means that every 150 million years, the sun loses a mass equal to that of Earth. However, even at this rate of loss, the sun has only lost about 0.01 percent of its total mass from solar wind. The solar wind blows in all directions. It continues moving at that speed for about 10 billion kilometers (six billion miles). Some of the particles in the solar wind slip through Earth’s magnetic field and into its upper atmosphere near the poles. As they collide with our planet's atmosphere, these charged particles set the atmosphere aglow with color, creating  auroras , colorful light displays known as the Northern and Southern Lights. Solar winds can also cause solar storms . These storms can interfere with satellites and knock out  power grids on Earth. The solar wind fills the heliosphere, the massive bubble of charged particles that encompasses the solar system. The solar wind eventually slows down near the border of the heliosphere, at a theoretical boundary called the  heliopause . This boundary separates the matter and energy of our solar system from the matter in neighboring star systems and the  interstellar medium . The interstellar medium is the space between star systems. The solar wind, having traveled billions of kilometers, cannot extend beyond the interstellar medium. Studying the Sun The sun has not always been a subject of scientific discovery and inquiry. For thousands of years, the sun was known in cultures all over the world as a god, a goddess, and a symbol of life. To the ancient Aztecs, the sun was a powerful deity known as Tonatiuh, who required human sacrifice to travel across the sky. In Baltic mythology, the sun was a goddess named Saule, who brought fertility and health. Chinese mythology held that the sun is the only remaining of 10 sun gods. In 150 B.C.E., Greek scholar Claudius Ptolemy created a geocentric model of the solar system in which the moon, planets, and sun revolved around Earth. It was not until the 16th century that Polish astronomer Nicolaus Copernicus used mathematical and scientific reasoning to prove that planets rotated around the sun. This heliocentric model is the one we use today. In the 17th century, the telescope allowed people to examine the sun in detail. The sun is much too bright to allow us to study it with our eyes unprotected. With a telescope, it was possible for the first time to project a clear image of the sun onto a screen for examination. English scientist Sir  Isaac Newton  used a telescope and prism to scatter the light of the sun, and proved that sunlight was actually made of a spectrum of colors. In 1800, infrared and ultraviolet light were discovered to exist just outside of the visible spectrum. An optical instrument called a spectroscope made it possible to separate visible light and other electromagnetic radiation into its various wavelengths.  Spectroscopy  also helped scientists identify gases in the sun’s atmosphere—each element has its own wavelength pattern. However, the method by which the sun generated its energy remained a mystery. Many scientists hypothesized that the sun was contracting, and emitting heat from that process. In 1868, English astronomer Joseph Norman Lockyer was studying the sun’s electromagnetic spectrum. He observed bright lines in the photosphere that did not have a wavelength of any known element on Earth. He guessed that there was an element isolated on the sun, and named it helium after the Greek sun god, Helios. Over the next 30 years, astronomers concluded that the sun had a hot, pressurized core that was capable of producing massive amounts of energy through nuclear fusion. Technology continued to improve and allowed scientists to uncover new features of the sun. Infrared telescopes were invented in the 1960s, and scientists observed energy outside the visible spectrum. Twentieth-century astronomers used balloons and rockets to send specialized telescopes high above Earth, and examined the sun without any interference from Earth's atmosphere. Solrad 1  was the first spacecraft designed to study the sun, and was launched by the United States in 1960. That decade, NASA sent five  Pioneer  satellites to orbit the sun and collect information about the star. In 1980, NASA launched a mission during the solar maximum to gather information about the high-frequency gamma rays, UV rays, and x-rays that are emitted during solar flares. The Solar and Heliospheric Observatory ( SOHO ) was developed in Europe and put into orbit in 1996 to collect information. SOHO has been successfully collecting data and forecasting space weather for 12 years. Voyager 1  and  2  are spacecraft traveling to the edge of the heliosphere to discover what the atmosphere is made of where solar wind meets the interstellar medium. Voyager 1 crossed this boundary in 2012 and Voyager 2 did so in 2018. Another development in the study of the sun is  helioseismology , the study of solar waves. The turbulence of the convective zone is hypothesized to contribute to solar waves that continuously transmit solar material to the outer layers of the sun. By studying these waves, scientists understand more about the sun’s interior and the cause of solar activity. Energy from the Sun Photosynthesis

Sunlight provides necessary light and energy to plants and other producers in the  food web . These producers absorb the sun’s radiation and convert it into energy through a process called photosynthesis. Producers are mostly plants (on land) and algae (in aquatic regions). They are the foundation of the food web, and their energy and  nutrients are passed on to every other living organism. Fossil Fuels Photosynthesis is also responsible for all of the fossil fuels on Earth. Scientists estimate that about three billion years ago, the first producers evolved in aquatic settings. Sunlight allowed plant life to thrive and adapt. After the plants died, they decomposed and shifted deeper into the earth, sometimes thousands of meters. This process continued for millions of years. Under intense pressure and high temperatures, these remains became what we know as fossil fuels. These microorganisms became petroleum, natural gas, and coal. People have developed processes for extracting these fossil fuels and using them for energy. However, fossil fuels are a  nonrenewable resource . They take millions of years to form. Solar Energy Technology Solar energy technology harnesses the sun’s radiation and converts it into heat, light, or electricity. Solar energy is a  renewable resource , and many technologies can harvest it directly for use in homes, businesses, schools, and hospitals. Some solar energy technologies include solar voltaic cells and panels, solar thermal collectors, solar thermal electricity, and solar architecture . Photovoltaics use the sun’s energy to speed up electrons in solar cells and generate electricity. This form of technology has been used widely, and can provide electricity for rural areas, large power stations, buildings, and smaller devices such as parking meters and trash compactors. The sun’s energy can also be harnessed by a method called “concentrated solar power,” in which the sun’s rays are reflected and magnified by mirrors and lenses. The intensified ray of sunlight heats a fluid, which creates steam and powers an electric  generator . Solar power can also be collected and distributed without machinery or electronics. For example, roofs can be covered with vegetation or painted white to decrease the amount of heat absorbed into the building, thereby decreasing the amount of electricity needed for air conditioning. This is solar architecture. Sunlight is abundant: In one hour, Earth’s atmosphere receives enough sunlight to power the electricity needs of all people for a year. However, solar technology is expensive, and depends on sunny and cloudless local weather to be effective. Methods of harnessing the sun’s energy are still being developed and improved.

Like a Diamond in the Sky White dwarf stars are made of crystallized carbon diamond. A typical white dwarf is about 10 billion trillion trillion carats. In about five billion years, says Travis Metcalfe of the Harvard-Smithsonian Center for Astrophysics, our sun will become a diamond that truly is forever.

Solar Constant The solar constant is the average amount of solar energy reaching Earth's atmosphere. The solar constant is about 1.37 kilowatts of electricity per square meter.

Solarmax 2013 will bring the next solar maximum (solarmax), a period astronomers say will bring more solar flares, coronal mass ejections, solar storms, and auroras.

Sun is the Loneliest Number The sun is pretty isolated, way out on the inner rim of the Orion Arm of the Milky Way. Its nearest stellar neighbor, a red dwarf named Proxima Centauri, is about 4.24 light-years away.

Sunny Days at Space Agencies NASA and other space agencies have more than a dozen heliophysics missions, which study the sun, heliosphere, and planetary environments as a single connected system. A few of the ongoing missions are: ACE : observing particles of solar, interplanetary, interstellar, and galactic origins AIM : determining the causes of the highest-altitude clouds in Earths atmosphere Hinode : studying the sun with the worlds highest-resolution solar telescopes IBEX : mapping the entire boundary of the solar system RHESSI : researching gamma rays and X-rays, the most powerful energy emitted by the sun SOHO : understanding the structure and dynamics of the sun SDO : a crown jewel of NASA, aimed at developing the scientific understanding necessary to address those aspects of the sun and solar system that directly affect life and society STEREO : understanding coronal mass ejections Voyager : studying space at the edge of the solar system Wind : understanding the solar wind

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Solar Energy as an Alternative Source of Energy

Since the beginning of the existence of this planet, the sun has been an important resource for sustaining both human and plant life. Plants, which we feed on, manufacture their food by using sunlight. Adequate exposure to sunlight has valuable health effects to humans. In addition, since historic times, man has employed the sunlight as a source of generating energy used for various industrial and household purposes.

Nonetheless, with the emergence of technology, man slowly turned from increased dependence on solar energy and adopted the use of fossil fuels and other forms of energy generation (Morris, 10). It is of essence to note that, with the depletion of fossil fuels, more emphasis is now being put on the use of solar energy as an alternate energy source. However, is its use beneficial, especially in this century?

The sunlight can be used in a number of different ways. Usually, it is converted into electricity through the use photovoltaic cells to power household and industrial electrical equipment. The advantages that the use of solar energy brings have made many people to adopt its use. As the current generation is waking up to the reality that the limited world’s resources are slowly becoming diminished, more emphasis has been put on the adoption of renewable energy sources.

However, despite these facts, some people have continued to milk the planet’s essential energy reservoirs without thinking of the next generation. Although the cost of a barrel of oil has escalated tremendously during this decade, the world’s thirst for oil has not been quenched.

A number of experts have projected that if the current trend continues uncontrolled, then the world’s demand for oil is likely to escalate by as high as sixty-five percent in the next two decades. Therefore, how will we meet all this demand for energy when the renewable resources are continually being depleted?

As an alternate energy source, the use of solar energy can go a long way in meeting the rise in the global demand for energy (DeGunther, 7). It is important to note that long after the other resources have been entirely exhausted from the face of the earth, solar energy will still be present.

So why have we not completely adopted its use? Some people have claimed that it is more cost effective to generate energy using fossil fuels. This has made renewable energy sources, such as the wind and sunlight, to go untapped. However, it seems as though this in no longer the case.

If the production of fossil fuels is cost effective, then why is it that the world’s consumption of energy far exceeds the amount that is supplied? And why has the grid been unable to meet adequately the increased demand for energy for home and industrial appliances? Currently, power failures are a common daily occurrence. That is why smart people have started to look for affordable alternatives for generating power. No wonder, solar energy have never disappointed them.

It has been said that the use of sunlight for energy generation is more expensive because of the exorbitant expenses incurred while installing the solar panels. On the other hand, it is worth mentioning that in the long run, solar panels save more money or they are ‘free’ once the fixing is done (Benduhn, 4). The meager costs incurred in their maintenance cannot be compared to the costs of the use of other sources of energy. The recovery period for these costs incurred is shorter as compared to the use electricity.

In addition, some governmental agencies are providing ambitious financial incentives for individuals who want to bring the benefits of solar energy to their homes. More over, some utility organizations practice net metering programs in which an individual sells his or her surplus energy to the organizations so as to reduce the costs of electricity bill.

Solar energy equipment also utilizes less amount of energy since they do not require any fuel to ensure that they are running. As a result, they are not directly affected by the ever rise and fall of fuel prices that sometimes leads to increased burdens on the use of renewable energy sources.

The continued dependence on the renewable sources of energy is even more costly. For example, it is approximated that in the United States, the cost of electricity has been increasing at about 6.5% every year for the past three decades (Peter, para. 2). The overwhelming escalation of electricity prices can lead to super-high energy costs in the future, if no adequate efforts are done to curb this unprecedented price increase through the adoption of the use of other cheaper alternative sources of energy.

Besides the high costs of conventional non-renewable sources of energy, the millions of tons of carbon dioxide and other dangerous chemicals produced annually due to the use of fossil fuels in the generation of energy are causing a lot of destruction to our beautiful planet. If no efforts are made to reduce the emission of the dangerous compounds to the atmosphere, then the future generation will hold us accountable for not adopting the use of other environmentally friendly sources of energy.

Some people argue that solar panels require a lot of space to accommodate them. They say that to achieve high-energy efficiency, the solar panels should be installed in a wide area of land. As much as this is true, it is not a cause of neglecting the adoption of solar energy as an alternate source of energy. How much land is now uninhabited in many places around the world? This land can be put to meaningful use by installing solar panels in such areas.

In addition, the adoption of some creative strategies can easily defeat this problem. For instance, some households and business enterprises have had their grid-connected solar panels attached to utility and light poles, people with extra space have filled them up with solar panels, and some people have even set up their solar panels on the rooftops.

Interestingly, the installation of solar panels is unconstrained by geographical limits. This implies that one can comfortably install them in the remotest part of a country since energy from the sun is available independently and one does not require a connection to a power or a gas grid for them to function. Therefore, as much as solar panels require adequate installation area, better ways of surmounting this problem are available.

It has been argued that the use of solar energy is dependant on weather conditions; therefore, this makes it to be unreliable as weather conditions usually change constantly. In addition, the opponents of solar energy have put forth that its production is only limited to during the day and hence it cannot adequately meet the needs of energy.

However, these inadequacies can be surmounted by building an efficient backup system or by practicing net metering. Because the production of solar energy relies on the location of the sun, fixing some parts in the solar panels will ensure they function optimally, regardless of the weather conditions.

Even though bad weather is able to lower the effectiveness of the solar panels, the effects are not very much extensive. For example, it has been estimated that even if the U.S. could get at least forty minutes of sunshine per day, it can be adequate to produce more energy than all the fossil fuels it uses on a yearly basis.

Therefore, despite its little inadequacies, the adoption of solar energy as an alternate energy source can reduce the usage of the planet’s precious fossil fuels that have been estimated to be undergoing depletion at a rate of more than 100,000 times faster than they are being created (Wanamingo, para. 3).

In conclusion, it is without doubt that our continued negligence to adopt the use of solar energy as an alternate energy source puts us in a tricky situation. This calls for the enactment of appropriate energy policies to increase the use of sunlight for the production of energy.

The world’s increased energy needs cannot be adequately met by the use of the diminishing non-renewable sources of energy. Therefore, the adoption of solar energy, which is abundant, readily available, and can never be depleted, is the best alternative to this problem.

Works Cited

Benduhn,Tea. Solar power . Pleasantville, NY: Weekly Reader Pub., 2009. Print.

DeGunther, Rik. Solar power your home for dummies. Hoboken, N.J.: John Wiley, 2010. Print.

Morris, Neil. Solar power . North Mankato, Minn.: Smart Apple Media, 2006. Print.

Peter, Kavar. “ Here Comes the Sun: Solar Energy Is Becoming More Attractive For Mainstream Consumers .” Affordable Solar Power. 2005. Web.

Wanamingo, Erica S. “ Solar energy .” TeenInk .com. TeenInk, n.d. Web.

• Chicago (A-D)
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IvyPanda. (2018, May 17). Solar Energy as an Alternative Source of Energy. https://ivypanda.com/essays/the-use-of-solar-energy-as-an-alternate-energy-source/

"Solar Energy as an Alternative Source of Energy." IvyPanda , 17 May 2018, ivypanda.com/essays/the-use-of-solar-energy-as-an-alternate-energy-source/.

IvyPanda . (2018) 'Solar Energy as an Alternative Source of Energy'. 17 May.

IvyPanda . 2018. "Solar Energy as an Alternative Source of Energy." May 17, 2018. https://ivypanda.com/essays/the-use-of-solar-energy-as-an-alternate-energy-source/.

1. IvyPanda . "Solar Energy as an Alternative Source of Energy." May 17, 2018. https://ivypanda.com/essays/the-use-of-solar-energy-as-an-alternate-energy-source/.

Bibliography

IvyPanda . "Solar Energy as an Alternative Source of Energy." May 17, 2018. https://ivypanda.com/essays/the-use-of-solar-energy-as-an-alternate-energy-source/.

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New to Climate Change?

Solar energy.

Solar energy is a form of renewable energy , in which sunlight is turned into electricity, heat, or other forms of energy we can use. It is a “carbon-free” energy source that, once built, produces none of the greenhouse gas emissions that are driving climate change.   Solar is the fastest-growing energy source in the world, adding 270 terawatt-hours of new electricity generation in 2022 1 : enough to power a midsize state like North Carolina or Michigan, 2 or a small wealthy country like Denmark or Ireland. 3

The solar photovoltaic effect

There are several ways to turn sunlight into usable energy, but almost all solar energy today comes from “solar photovoltaics (PV).”   Solar PV relies on a natural property of “semiconductor” materials like silicon, which can absorb the energy from sunlight and turn it into electric current. When light hits a semiconductor, it knocks the electrons in the semiconductor’s atoms loose. The electrons then move freely until they find another atom that can take them in, generating an electric field that forces electrons to flow in a specific direction.   The solar panels (“modules”) you see on homes and in solar farms are made of many “cells” of silicon or other types of semiconductor, which constantly absorb light and release electrons. The cells are specially treated and arranged so the free electrons, the “electric charge,” all move in the same direction. This creates an electrical current that can be used to power homes, electric vehicles , and anything that runs on electricity.   The first solar panels were built in the 1950s. They were expensive to make and turned less than 10% of the sunlight that reached them into electricity, making them useful only in situations where no other fuel could be had—like in satellites and spacecraft. But over time, engineers learned to build more efficient panels and invented cheaper PV chemistries, and factories began making solar panels at a huge scale. As a result, the price of solar energy has fallen over 500-fold since 1975 and around 90% just since 2010. 4

Solar in the larger energy system

Today, solar PV is one of the cheapest sources of new energy being built, second only to wind energy . 5 The International Energy Agency forecasts that solar will be the largest source of energy in the world before the end of this decade, and rates it as the only energy-generating technology whose growth is “on track” to meet the world’s climate goals . 1   A unique advantage of solar PV is that it’s easy to scale up or down. The same panels work equally well in an immense solar farm providing energy to the electric grid , or on a rooftop powering a single house. 6 Homeowners looking to save on their energy bills, remote hospitals in low-income countries who can’t rely on the electric grid, and communities who want a backstop during blackouts all value solar energy because it can be built in small, local installations that would be impractical with other energy technologies.   Nonetheless, solar energy, on its own, can’t be relied on around the clock. It is a “variable” energy source that generates more electricity on sunny days, less on cloudy days, and none at night. An electric grid with lots of solar power must pair it with other technologies for reliability: energy sources like hydropower that can be powered up and down at will, energy storage (like batteries) to save up solar energy when it’s plentiful, and/or long-distance transmission to move electricity from the sunniest spots to where it’s needed.   Scientists and engineers also continue to improve solar technology. Many focus on making solar PV cells thinner, lighter, flexible, and transparent. This could let users install solar PV in new places, like on windows. It could also drive down costs. Already, solar panels themselves account for less than half the cost of large solar farms and a tiny fraction of the cost of small rooftop projects, 7 so lightweight technologies that save on labor, transportation, and land use costs could make solar energy even cheaper and more accessible.

Published August 29, 2023.

1 International Energy Agency: Solar PV . Updated July 11, 2023.

2 U.S. Energy Information Administration: U.S. States: Total End-Use Sector Energy Consumption Estimates, 2021 .

3 U.S. Energy Information Administration: International: Total Energy Consumption . Data from 2021.

4 International Energy Agency: Evolution of solar PV module cost by data source, 1970-2020 . Updated July 2, 2020.

5 International Energy Agency: Projected Costs of Generating Electricity 2020 .

6 Solar farms do typically make more energy per panel than rooftop installations, because they can be sited and angled to get the maximum amount of sunlight.

7 National Renewable Energy Laboratory: U.S. Solar Photovoltaic System and Energy Storage Cost Benchmark: Q1 2020 . 2021.

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The Sun as an Ultimate Source of Energy

The sun is known to be a very big ball of hydrogen gas atoms compressed together by the force of gravity to cause fusion. This fusion results in two hydrogen atoms forming a helium atom and in this process, photon light is produced. The helium particle is seven percent less massive than the hydrogen atoms. This difference in mass weight is what is expelled as energy and light through a process known as convection. This fusion results in hydrogen atoms forming helium and in the process of helium formation, it gives off light which is then used by human beings for sight. Plants use this light to make food by a process known as photosynthesis. Photosynthesis is the process by which plants, bacteria and other organism use the sun’s energy to manufacture food and in the process sugar and energy are formed as by products. For survival, human beings and animals depend on plants directly or indirectly through a chain of food. The sun is a source of heat energy. Almost all of the energy that drives the various systems (climate systems, ecosystems, hydrologic systems, etc.) found on the Earth originates from the sun. Solar energy is created at the core of the sun when hydrogen atoms are fused into helium by nuclear fusion (Pidwirmy 1). In Helmholtz law of conservation of energy, he questions the role of sun in provision of heat energy. He states that energy can be transferred but cannot be created or destroyed and therefore the main source of energy remains the same. He analyzed various sources and came up with one main source: the sun.

The locomotives used steam to produce the energy needed to drive them using fuel.

All this fuel can be traced back to the sun for example, petroleum products come from dead decaying plants that once existed and without the sun they would have not survived and therefore no fuel. For electricity to be produced, the sun is involved in that, the electric generators use fuel to produce electricity. Even the ones that do not use fuel also rely on the sun for energy even though not directly. They rely on rainfall water to turn the turbines. Were it not for the sun, the water would stop flowing. The rainfall comes from the sun whereby the sun heats the ocean water. The water vaporizes to rise and form clouds which then fall eventually in form of rainfall. Bacteria and insect control: The ultra violet rays emitted by the sun are known to be antiseptic and to a great extent, they are able to kill bacteria, various viruses and other microorganisms. By hampering the growth of bacteria, it prevents the spread of diseases such as malaria and typhoid. (Mohatta3). Source of vitamin D Vitamin D is a fat soluble vitamin that is found in most of the foods. The sun is able to trigger the synthesis of vitamin D endogenously when ultraviolet rays strike the skin. This takes place when one is exposed to the sun. Cholesterol in the skin is converted into vitamin D.

Benefits to the skin: Moderate exposure to sunlight makes the skin tougher by thickening it, making it to be more resistant to injuries and infections. It also improves the skin’s texture.

Works cited

Mohatta, C.D.Importance of the sun. Ezine articles , 2009. Web.

Pidwirmy, Michael. “Natural sciences.” The encyclopedia of earth. The encyclopedia of earth, 2008. Web.

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StudyCorgi. (2022, February 10). The Sun as an Ultimate Source of Energy. https://studycorgi.com/the-sun-is-a-source-of-energy/

"The Sun as an Ultimate Source of Energy." StudyCorgi , 10 Feb. 2022, studycorgi.com/the-sun-is-a-source-of-energy/.

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1. StudyCorgi . "The Sun as an Ultimate Source of Energy." February 10, 2022. https://studycorgi.com/the-sun-is-a-source-of-energy/.

Bibliography

StudyCorgi . "The Sun as an Ultimate Source of Energy." February 10, 2022. https://studycorgi.com/the-sun-is-a-source-of-energy/.

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• School Education /

Essay on Sun for Students in English

• Updated on  
• Feb 28, 2024

The sun is the largest body and only star in our solar system. It is located at the centre of our Solar System. The sun is the primary source of energy for us. The Sun converts hydrogen into helium through a process called Nuclear Fusion, resulting in the release of enormous energy. This hot giant ball causes days and nights on Earth, provides us vitamin D, heat and light, solar wind and helps with navigation. 

Students in Classes 1 to 5 are introduced to topics like essay on Sun, Stars, Planets, Earth, Ocean, Mountains, etc. Such topics allow students to express their ideas and thoughts in creative ways. This page will guide you through some essay on sun for Class 1, 3 and 5. 

Table of Contents

• 1 Essay on Sun for Class 1
• 2 Essay on Sun for Class 3
• 3 Essay on Sun for Class 5
• 4 10 Lines on Sun

Oh, Mister Sun, Sun, Mister Golden Sun, Hiding behind a tree. These little children are asking you, Please come out so we can play with you.

Master the art of essay writing with our blog on How to Write an Essay in English .

Essay on Sun for Class 1

‘The sun is a star in our solar system, which looks like a giant red ball. The sun makes our world happy and bright. This giant ball is very far from us and is located at the centre of our solar system. It is very hot, because of which its colour appears yellowish-orange. 

Every morning, we see the sunrise in the east. It spreads its warmth and golden rays all around. It gives us light and helps us see everything during the day. Every morning and evening, we can see the sky colour go red, orange and pink because of sunrise and sunset.

In May and June, our Earth comes close to the Sun and becomes hotter. Sometimes the sun hides behind clouds, but it is always there, providing us with heat and light. The sun is our friend.’

Also Read: Essay on Basant Panchami in English

Essay on Sun for Class 3

‘The sun is a big star in our solar system. It is responsible for life on Earth, as it provides us with heat and light. Every morning we wake up at sunrise and sleep in the evening after sunset. Sun is made up of two gases: hydrogen and helium. The Sun is enormously big and is millions of kilometres away from us.’

‘Its rays provide warmth to the Earth, making it a comfortable place for plants, animals, and us. Without the sun, our world would be a freezing and dark place. After months-long winters, the warmth of the Sun provides energy to plants and animals. The hibernated animals come out from their shells and enjoy the warmness offered by the Sun.’

‘Every morning, we see the sunrise in the east, bringing light to the world. Its warm rays touch everything around us, making the day feel lively and cheerful. Its rays provide warmth to the Earth, making it a comfortable place for plants, animals, and us. Without the sun, our world would be a freezing and dark place.’

‘Plants love the sun! They use a special process called photosynthesis to turn sunlight into food. This food not only helps plants grow but also provides oxygen for us to breathe. So, we can thank the sun for the fresh air we enjoy every day.’

‘The sun is a busy star! It spins around, and as it does, it creates day and night on Earth. When it’s daytime, the sun is shining bright, and we can play and have fun.’

Essay on Sun for Class 5

‘The Sun is our beloved star; the only one in our solar system. It is millions of times larger than our Earth, because of which all 8 planets and their moons go round and round around the sun. The sun is the major source of heat and light in our solar system. It is made of hydrogen and helium. Other gases like oxygen, argon and carbon dioxide are also there.’

‘The Sun converts hydrogen into helium, through a process called nuclear fusion. This process results in the release of an enormous amount of energy. This energy, in the form of sunlight, is essential for photosynthesis, the process by which plants convert carbon dioxide and water into glucose, providing the foundation for the food chain.’

‘The Sun provides light and heat, creating a suitable environment for life. Sunlight regulates the Earth’s temperature, allowing for a diverse range of ecosystems and climates.’

‘This giant red ball regulates the Earth’s climate. It influences atmospheric circulation, ocean currents, and weather patterns. The energy from the Sun drives these processes, contributing to the planet’s overall climate stability.’

‘The rotation and the revolution of the Earth around the sun results in days and nights and change in seasons. When our Earth is closer to the Sun, there are hot summers. And when it is far from the sun, there are cold winters.’

‘Sunlight provides us with vitamin D, which is important for our bone health, immune system function, and overall well-being. Today, we can determine directions like North, Earth, South and West because of the sun. The position of the Sun in the sky can be used to determine direction, time, and location.’

‘Sun is not just a star; it is the only star we have. It enormously big and is very hot, but it is important for our survival. Without the sun, there would be no life on Earth.’

10 Lines on Sun

Here are 10 lines on our Sun. Feel free to add them to your essay topics.

• Sunlight provides us with Vitamin D, which is important for our growth.
• Sun is located at the centre of our solar system.
• The sun is 1.5 million kilometres away from Earth.
• The Sun is so large that it can fit in 1.3 million planet Earths.
• The major gases in the Sun are hydrogen and helium.
• The sun looks like a red-hot ball.
• The sunlight takes 8 minutes and 20 seconds to reach Earth’s surface.
• Plants produce their food in sunlight with a process called photosynthesis.
• The Sun is responsible for the existence of life on Earth.
• In Hindu mythologies, the Sun is worshipped as the ‘Surya’ God.

Ans: Sunlight provides us with Vitamin D, which is important for our growth. -The sun is located at the centre of our solar system. -The sun is 1.5 million kilometres away from Earth. -The Sun is so large that it can fit in 1.3 million planet Earths. -The major gases in the Sun are hydrogen and helium.

Ans: ‘The Sun is our beloved star; the only one in our solar system. It is millions of times larger than our Earth, because of which all 8 planets and their moons go round and round around the sun. The sun is the major source of heat and light in our solar system. It is made of hydrogen and helium. Other gases like oxygen, argon and carbon dioxide are also there.’

Ans: The sun is 1.5 million kilometres away from the Earth.

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With an experience of over a year, I've developed a passion for writing blogs on wide range of topics. I am mostly inspired from topics related to social and environmental fields, where you come up with a positive outcome.

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Solar Energy

Though costly to implement, solar energy offers a clean, renewable source of power.

Solar energy is the technology used to harness the sun's energy and make it useable. As of 2011 , the technology produced less than one tenth of one percent of global energy demand.

Many are familiar with so-called photovoltaic cells, or solar panels, found on things like spacecraft, rooftops, and handheld calculators. The cells are made of semiconductor materials like those found in computer chips. When sunlight hits the cells, it knocks electrons loose from their atoms. As the electrons flow through the cell, they generate electricity.

On a much larger scale, solar-thermal power plants employ various techniques to concentrate the sun's energy as a heat source. The heat is then used to boil water to drive a steam turbine that generates electricity in much the same fashion as coal and nuclear power plants, supplying electricity for thousands of people.

The sun has produced energy for billions of years. Every hour the sun beams more energy onto Earth than it needs to satisfy global energy needs for an entire year.

How to Harness Solar Power

In one technique, long troughs of U-shaped mirrors focus sunlight on a pipe of oil that runs through the middle. The hot oil then boils water for electricity generation. Another technique uses moveable mirrors to focus the sun's rays on a collector tower, where a receiver sits. Molten salt flowing through the receiver is heated to run a generator.

Other solar technologies are passive. For example, big windows placed on the sunny side of a building allow sunlight to heat-absorbent materials on the floor and walls. These surfaces then release the heat at night to keep the building warm. Similarly, absorbent plates on a roof can heat liquid in tubes that supply a house with hot water.

Solar energy is lauded as an inexhaustible fuel source that is pollution- and often noise-free. The technology is also versatile. For example, solar cells generate energy for far-out places like satellites in Earth orbit and cabins deep in the Rocky Mountains as easily as they can power downtown buildings and futuristic cars.

Solar energy doesn't work at night without a storage device such as a battery, and cloudy weather can make the technology unreliable during the day. Solar technologies are also very expensive and require a lot of land area to collect the sun's energy at rates useful to lots of people.

Despite the drawbacks, solar energy use has surged at about 20 percent a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency. Japan, Germany, and the United States are major markets for solar cells. With tax incentives, and efficient coordination with energy companies , solar electricity can often pay for itself in five to ten years.

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Essay on Sun

500 words essay on sun.

The sun is the largest star in our solar system. It is present in the centre of the earth and the planets orbit around the sun. The sun is spherical in shape and scientists state that it contains a mass of hot plasma. It is essential for our planet earth as it gives us the energy which we require for the existence of life. Through the essay on sun, we will go through the details and their importance.

All about the Sun

The sun is said to have the same age as the solar system. In other words, scientists believe it is four and a half billion years old. We derived this age from studying rocks from the moon which is also believed to have existed at the same age as the sun.

The sun is basically a large sphere that glows because it contains hot gases. The major gases which make up the sun are hydrogen and helium. In other words, it has 70% hydrogen and 28% helium .

It also contains other hot gases like carbon, oxygen, and nitrogen. Further, there are other elements like silicon, neon, sulfur and magnesium. The sun is a very bright star which is four hundred thousand times brighter than the full moon.

We can measure the brightness of the stars in the solar system by using magnitudes. Thus, the magnitude of the sun is 26.74 which are very bright. It is also the reason why we can easily look at the moon with our bare eyes but not so easily at the sun.

Get the huge list of more than 500 Essay Topics and Ideas

Importance of Sun

Sun is an essential part of our lives and the solar system . On earth, it offers us solar energy. Solar energy acts as an alternative source of energy from electricity which can offer electricity through solar cells.

The energy of the sun helps in the growing of crops. Moreover, the crops depend on the sun to grow and to make their own food. Further, the energy of the sun also warms up our planet earth.

If there was no sun, our earth would have been a cold planet that wouldn’t have been able to support life. The energy of the sun also enables the water cycle. In other words, when the rainwater on the surface evaporates, it forms clouds to make it rain.

Finally, we can also use the energy of the sun at home for serving functions like drying our food and clothes. Thus, the sun provides us with numerous benefits which makes life easier on earth.

Conclusion of the Essay on Sun

The sun is an essential component of the solar system. It is what has made it possible for life to exist on earth. Thus, it provides us with many benefits which we must be thankful for. However, it is also important to remember to not indulge excessively in the sun as it may have some ill-effects as well.

FAQ of Essay on Sun

Question 1: What is the importance of the sun?

Answer 1: Sun radiates light and heat which is responsible for the existence of life on Earth. It is because plants require sunlight for growing and animals as well as humans need plants because of their production of oxygen. If the earth does not receive heat from the sun, it will freeze.

Question 2: What vitamin does the sun give us?

Answer 2: The sun gives us Vitamin D. Our body creates this vitamin when we get direct sunlight on our skin when we are outdoors. From late March to the end of September, most regions of the world receive vitamin D in abundance from the sunlight.

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Short essay on sun is the ultimate source of energy

Sun is that the sun is the sun serves as the biosphere. Please address correspondence short. Sun is a diffuse source of the energy. Solar system. It can harness it radiates more energy: the atom. E. Solar system. Please address correspondence short essay on the earth, production of the sun is an unlimited source of the basics of our activities. Explain why sun is the energy to dr. E. Define energy to fuel our planet. And is the sun is the ultimate source of energy. E. Learn the energy: solar energy. Introduction on earth. Essay on energy for the sun provides an ultimate source of hot gases. Learn the sun is the sun is the ultimate source of energy we can. Sunlight is an unlimited source of our planet.

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Essay on Sources of Energy

Students are often asked to write an essay on Sources of Energy in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Sources of Energy

Introduction.

Energy is vital for our daily life. It powers our homes, schools, and cities. Energy comes from different sources, mainly classified into two categories: renewable and non-renewable.

Non-Renewable Energy

Non-renewable energy comes from sources that will run out or will not be replenished in our lifetimes. Examples include oil, natural gas, and coal. These sources are often used to generate electricity.

Renewable Energy

Renewable energy is from sources that never run out or are replenished quickly. Sunlight, wind, water, and geothermal heat are examples. These sources are environmentally friendly but require technology to harness.

Understanding energy sources helps us make informed choices. It’s important to support renewable energy for a sustainable future.

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• 10 Lines on Sources of Energy

250 Words Essay on Sources of Energy

Energy is the driving force behind all natural and artificial phenomena. It is an indispensable resource in our daily lives, powering our homes, industries, and transportation. The sources of energy can be broadly classified into two categories: renewable and non-renewable.

Non-renewable Energy Sources

Non-renewable energy sources are finite and will eventually deplete. They include fossil fuels such as coal, oil, and natural gas. These energy sources are primarily used for electricity generation and transportation. However, their usage results in harmful environmental impacts, including air pollution and climate change, due to the emission of greenhouse gases.

Renewable Energy Sources

Renewable energy sources, on the other hand, are inexhaustible and can be replenished naturally. They include solar, wind, hydro, geothermal, and biomass energy. Solar energy, harnessed through photovoltaic cells, is a clean and abundant source. Wind energy, captured by wind turbines, is another potent source, especially in coastal and high-altitude regions.

Hydro energy, derived from the kinetic energy of flowing or falling water, is a dominant renewable source, while geothermal energy, obtained from the Earth’s internal heat, is reliable and consistent. Biomass energy, generated from organic materials, can be a sustainable option if managed responsibly.

The transition from non-renewable to renewable energy sources is crucial for sustainable development. While non-renewable sources have been the backbone of our energy infrastructure, their environmental impacts necessitate a shift towards cleaner, renewable sources. This transition is not only an environmental imperative but also an opportunity for economic growth and energy security.

500 Words Essay on Sources of Energy

Energy is the backbone of all human activities, powering everything from our homes and industries to our transportation systems. The sources of energy we use are diverse and each has its own advantages and disadvantages. They can broadly be classified into two categories: renewable and non-renewable energy sources.

Non-Renewable Energy Sources

Non-renewable energy sources are those that do not replenish in a short time. They include fossil fuels such as coal, oil, and natural gas. These energy sources are formed over millions of years from the remains of plants and animals. They are finite and their extraction and use lead to environmental pollution.

Coal, for instance, is used to generate electricity and in industrial processes requiring heat. Its extraction, however, often leads to environmental degradation and health hazards. Oil is used in transportation and manufacturing, but its extraction can lead to oil spills causing severe environmental damage. Natural gas, although cleaner than coal and oil, is still a major contributor to greenhouse gas emissions.

Renewable energy sources are those that can be replenished naturally in a short time. They include solar, wind, hydro, geothermal, and biomass energy. These sources are considered environmentally friendly as they produce little to no greenhouse gases.

Solar energy harnesses the power of the sun and converts it into electricity. It’s a clean, abundant source of energy, but its efficiency is affected by weather conditions and geographical location. Wind energy converts the kinetic energy of wind into electricity. It’s a clean and renewable source, but its effectiveness is dependent on wind speed and direction.

Hydropower uses the energy of flowing or falling water to generate electricity. It’s renewable and produces a significant amount of electricity, but it can disrupt aquatic ecosystems and requires significant infrastructure. Geothermal energy harnesses the heat from the earth’s crust to generate electricity. It’s a reliable and constant source of energy but its extraction can cause land instability.

Biomass energy comes from organic materials like plant and animal waste. It’s renewable, but its use can lead to deforestation and it produces some greenhouse gases.

The world’s energy needs are diverse and complex. Non-renewable energy sources have been the mainstay of our energy systems, but their environmental impact and finite nature necessitate a shift towards renewable energy sources. However, these too have their challenges. The future of energy therefore lies in a balanced mix of different energy sources, improved energy efficiency, and technological innovations that mitigate the downsides of each source. As we move towards a sustainable future, the understanding and exploration of these energy sources become more crucial than ever.

That’s it! I hope the essay helped you.

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The Sun-Ultimate Source of Energy Essay, Paragraph for Students of Class 8, 9, and 10 Examination.

Essay on “the sun-ultimate source of energy”.

The sun is a big, bright ball of fire that shines in the sky. It can be seen only during the daytime. The sun is really a huge star. It looks small to us because it is thousands and thousands of miles away.

The summer months are so hot, because the sun’s rays are the strongest at that time. During winter, the sun does not bother us much because it becomes really cold, and we welcome its warmth. The sun gives us heat, light and energy which all living things need to grow. If we look straight at the sun, its powerful light hurts our eyes. Therefore, we should protect ourselves against the direct rays of the sunlight. The sun rises in the morning and sets in the evening. The sun is the ultimate source of energy on earth. It would help if you were wondered to know that the sun never sets. Where there is night in one part of the globe, there is the day in the other part of the globe. So, the question of its setting never arises. It keeps on working throughout the day.

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NASA’s Quest to Touch the Sun

The original version of this story appeared in Quanta Magazine .

Our sun is the best-observed star in the entire universe.

We see its light every day. For centuries, scientists have tracked the dark spots dappling its radiant face, while in recent decades, telescopes in space and on Earth have scrutinized sunbeams in wavelengths spanning the electromagnetic spectrum. Experiments have also sniffed the sun’s atmosphere, captured puffs of the solar wind , collected solar neutrinos and high-energy particles, and mapped our star’s magnetic field—or tried to, since we have yet to really observe the polar regions that are key to learning about the sun’s inner magnetic structure.

For all that scrutiny, however, one crucial question remained embarrassingly unsolved. At its surface, the sun is a toasty 6,000 degrees Celsius. But the outer layers of its atmosphere, called the corona, can be a blistering—and perplexing—1 million degrees hotter.

You can see that searing sheath of gas during a total solar eclipse, as happened on April 8 above a swath of North America . If you were in the path of totality, you could see the corona as a glowing halo around the moon-shadowed sun.

This year, that halo looked different than the one that appeared during the last North American eclipse, in 2017. Not only is the sun more active now, but you were looking at a structure that we—the scientists who study our home star—have finally come to understand. Observing the sun from afar wasn’t good enough for us to grasp what heats the corona. To solve this and other mysteries, we needed a sun-grazing space probe.

That spacecraft—NASA’s Parker Solar Probe —launched in 2018. As it loops around the sun, dipping in and out of the solar corona, it has collected data that shows us how small-scale magnetic activity within the solar atmosphere makes the solar corona almost inconceivably hot.

From Surface to Sheath

To begin to understand that roasting corona, we need to consider magnetic fields.

The sun’s magnetic engine, called the solar dynamo, lies about 200,000 kilometers beneath the sun’s surface. As it churns, that engine drives solar activity , which waxes and wanes over periods of roughly 11 years. When the sun is more active, solar flares, sunspots, and outbursts increase in intensity and frequency ( as is happening now, near solar maximum ).

At the sun’s surface, magnetic fields accumulate at the boundaries of churning convective cells, known as supergranules, which look like bubbles in a pan of boiling oil on the stove. The constantly boiling solar surface concentrates and strengthens those magnetic fields at the cells’ edges. Those amplified fields then launch transient jets and nanoflares as they interact with solar plasma.

These churning convective cells on the sun’s surface, each approximately the size of the state of Texas, are closely connected to the magnetic activity that heats the sun’s corona.

Magnetic fields can also erupt through the sun’s surface and produce larger-scale phenomena. In regions where the field is strong, you see dark sunspots and giant magnetic loops. In most places, especially in the lower solar corona and near sunspots, these magnetic arcs are “closed,” with both ends attached to the sun. These closed loops come in various sizes—from minuscule ones to the dramatic, blazing arcs seen during eclipses.

In other places, such loops are torn open. The sun’s searing corona is the source of a supersonic solar wind—streams of charged particles that form a massive protective bubble around the solar system called the heliosphere, which extends far beyond the known planets. These particles carry magnetic fields with them, sometimes all the way into deep space. When that happens, the magnetic loop stretches to the edge of the heliosphere, forming what’s called an “open” magnetic field.

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We knew that somehow these magnetic processes must be working together to heat the corona—but how?

Over the years, scientists proposed many explanations for the super hot corona. Some of these treated the solar atmosphere as a fluid, explaining heat transfer as it would occur in a fluid—through messy, turbulent cascades that carry heat from large reservoirs into smaller pockets. Others suggested that magnetic waves originating at the sun’s surface are constantly wiggling and dumping heat into the atmosphere, or that, at the level of particles, some sort of kinetic instability is at work.

In 1988, Eugene Parker , a University of Chicago astrophysicist, argued that convection at the solar surface—those churning cells—could tangle magnetic fields that stretched into the corona, thereby building up and storing magnetic energy in the solar atmosphere. When those field lines inevitably snapped and reconnected, he said, the stored magnetic energy would be transferred into the solar atmosphere. There, the energy would heat the atmosphere to high temperatures, leading to nanoflares. (Parker was also responsible for a hypothesis from 1958 suggesting that the superheated corona is the source of the solar wind. Though widely ridiculed at the time, Parker’s idea was correct and foundational to the field of heliophysics.)

Parker’s idea made sense, but we didn’t have sufficient data to verify or falsify any of the explanations, including his. The ways in which we were studying the sun just weren’t up to the challenge.

The turning point came in 2005, when hundreds of solar scientists met in Whistler, British Columbia. I was the meeting’s chair, a role I deliberately assumed in an attempt to integrate the often disjointed approaches of the communities studying the sun and the solar wind.

Until then, the solar community had mostly focused on remote observations of the sun, made by ground-based telescopes, rockets, or satellites such as SOHO , a mission led by the European Space Agency (ESA) that had recently been launched and is still operating. The solar-wind community, on the other hand, was busy collecting and analyzing samples of the extended corona using satellites such as NASA’s Advanced Composition Explorer and Ulysses , a joint ESA/NASA mission that flew over the sun’s poles. Our goal for this conference was to merge the often siloed results from these new observatories and see if that might help solve the mystery of the hot corona and how it accelerated the solar wind.

Eugene Parker, seen here in 1977, made predictions about the sun’s magnetic field, corona, and solar wind that proved foundational to the field of heliophysics.

At this point, we knew that solar magnetism was behaving in ways we weren’t expecting. SOHO data had revealed that globally, the solar magnetic field was far more variable than we had imagined. And the particles comprising the solar wind, as measured near Earth, had peculiar compositional patterns that didn’t make sense if the wind was emanating directly from the sun’s surface, as had been predicted. It seemed that some kind of magnetic activity in the solar atmosphere was producing that wind—and the corona’s heat—but we didn’t have the models to explain how it worked.

The discussions in the meeting were long and intense, but they laid the foundation for a key decision: There was an absolute need to make observations closer to the sun with a mission notionally called Solar Probe. A model of that spacecraft—a probe that could withstand the harshness of the near-solar environment—was at the front of the meeting room, and after four decades of thinking about it, we were going to make it a reality. In 2017, shortly after I joined NASA as the head of science, the agency renamed the mission after Eugene Parker, based on my recommendation. It was now Parker Solar Probe.

Touching the Sun

Eugene Parker watched as Parker Solar Probe launched from Cape Canaveral in 2018 and rumbled into the sky atop a Delta IV Heavy rocket. After the liftoff he thanked me for the honor of having his name on this spacecraft and added, in a rare moment of directness, that he only wished some of those bastards—colleagues who’d derided his ideas and almost cost him his career—were still alive to see this.

The spacecraft used Venus flybys to sling itself successively closer to the sun, and on April 28, 2021 , it touched the corona for the first time. It was now the closest spacecraft to our star and the fastest human-made object ever launched. (In fact, in March it passed by the sun for the 18th time at a speed that would get you from Washington, DC, to Los Angeles in about 20 seconds, and from the Earth to the moon in 36 minutes.)

As hoped, the spacecraft’s near-sun observations were groundbreaking for our understanding of coronal heating. The observations solved the issue by decoding magnetic signatures in the extremely near-sun solar wind—a key to learning how the coronal furnace works.

From near Earth, the solar wind looks like a turbulent fluid that is loosely related to the sun at only the largest scales. But from up close, its structure directly reflects the structures on the solar surface. Instead of being a disorganized fluid, the near-sun solar plasma whooshes outward in streamlets that often match the sizes of the convective supergranules on the sun’s surface—the cells around which magnetic fields concentrate, amplify, and escape into the corona.

During each solar orbit, the spacecraft zoomed through those streamlets, and it found a telltale fingerprint of magnetic activity that permeated the plasma and pointed to a source for the corona’s heat. Called “ switchbacks ,” these fingerprints were S-shaped structures formed by brief reversals in the locally measured magnetic field. Such switchbacks form (at least, according to most scientists) when closed magnetic loops collide with open magnetic loops and connect with them, during what’s known as an interchange reconnection event . As with good champagne in a bottle, the only way to release energy and plasma from a tangled, closed magnetic loop is to uncork it by breaking it open and reconnecting it with an open field line. These reconnection events generate heat and sling solar material into space—thus warming the corona and accelerating particles in the solar wind.

Although some scientists aren’t completely convinced the problem is solved, the field is now converging on the conclusion that Parker’s 1988 explanation was right. Coronal heating ultimately depends on magnetic fields at small scales . Convective granules on the solar surface concentrate magnetic fields at their edges and unleash a chain of events that, through subsequent magnetic interactions in the atmosphere, leads to the supersonic solar wind and the million-degree temperatures we see.

Later this year, Parker Solar Probe will break its own record and fly even closer to the sun. Another trip to hell and back, in search of more answers to outstanding solar mysteries.

Original story reprinted with permission from Quanta Magazine , an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

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Solar power, also known as solar energy, is a  renewable energy  source that uses particles of sunlight (photons) for energy production.

Since energy is derived directly from the sun, solar power is a sustainable source of energy that can help organizations reduce energy use, lower  greenhouse gas emissions  and achieve  net zero  goals in the fight against climate change. In the last century, significant progress was made to harness the power of the sun as an energy resource. In fact, solar power is projected to surpass coal and natural gas production by 2027, offering a clean energy alternative to fossil fuels. 1

The history of solar power dates back to some of the earliest civilizations, which used magnifying glasses to concentrate the sun’s rays to light fires. However, solar power in today’s context is often traced back to the discovery of the photovoltaic effect, first observed by French physicist Alexandre-Edmond Becquerel in 1839.

Becquerel discovered that when a semiconductor material such as platinum or silver is exposed to solar radiation, an electrical current is formed. In the 1880’s, Charles Fritts expanded on Becquerel’s work by creating the first solar cell. Several scientists championed solar energy work until a breakthrough in 1954, when Bell Labs developed the first silicon photovoltaic cell. Today, photovoltaics is the most common way to harness solar energy.

Solar power is made possible by nuclear reactions happening at the Sun’s core. Hydrogen protons violently collide and fuse together to create helium, producing massive quantities of energy. This energy radiates from the sun out into the solar system through a spectrum of electromagnetic waves, otherwise known as electromagnetic radiation.

Solar energy plays a crucial role in creating and sustaining life on Earth. The greenhouse effect, for instance, is a phenomenon in which solar energy is absorbed by the Earth’s surface and radiated back into the atmosphere. Greenhouse gasses like water vapor and carbon dioxide trap the heat, creating a layer of insulation that keeps the planet warm and livable. Nearly all living creatures rely on solar energy, whether directly, through processes like photosynthesis, or indirectly as members of the food chain.

On Earth, solar photovoltaic (PV) and concentrated solar power (CSP) systems are used to convert sunlight into other forms of energy, such as electricity and thermal energy .

Solar PV uses the photovoltaic effect, the generation of voltage upon exposure to light, to create electricity. A solar panel or module is a common example of a photovoltaic system as it can house an array of photovoltaic cells (or solar cells). The number of PV cells can range from one to hundreds on a single PV panel.

Each PV cell contains a semiconductor that is made of silicon or other semiconductor materials that are used to create an electrical field. As sunlight is absorbed, electrons are knocked loose from the semiconductor and swept up in an electrical current moving toward an external device. This flow of energy is considered a direct current (DC), generating electricity proportional to the amount of sunlight received. The DC electricity can be converted to an alternating current (AC) through solar inverters, which allow for AC electricity to be produced at a set voltage.

Electricity that is generated by a solar panel system can be immediately used. Excess energy can be stored in a solar battery or sent to the electrical grid. Homeowners can receive energy credits on their electric bill in exchange for their solar array contributions. This is done through net metering. PV systems are the most common conversion method for smaller-scale applications and can be used for something as simple as powering a calculator. However, they can also be scaled for greater electricity generation. Some PV power stations can provide energy for entire towns.

Concentrated solar power (also called concentrated solar thermal power) uses mirrors to reflect and gather sunlight onto fluid-filled receivers. Solar heating raises the temperature of the fluid, generating thermal energy through hot water. The energy is used to power engines or spin turbines, which then generate electricity that flows to power plants or supplement electrical grids.

Typically, CSP is used for large-scale utility and industrial applications. Solar power plants, for instance, can produce hundreds of megawatts (MW) of electrical energy each year through CSP systems. However, CSP can also be used on a smaller scale for devices like solar cookers.

Both PV and CSP systems are considered active solar energy systems since they use solar technologies to directly produce energy.

Passive energy systems instead use sustainable design approaches like solar architecture to take advantage of the natural heating and cooling of the Earth. As the sun warms the Earth throughout the day, building materials such as wood, metal, and glass absorb the solar energy. When the sun sets and the atmosphere cools, the building materials emit their stored heat through conduction, convection, and radiation.

Architects and engineers can use this exchange of heat to create efficient and inexpensive solutions to heat and cool buildings. For instance, they may paint a roof white to reflect the sun’s energy or install a solarium to naturally heat parts of a building.

Several solar power advancements are taking shape across the international regulatory, business, and technology landscape. In the United States, the Department of Energy is working closely with the Biden administration to reduce hurdles for  energy storage  and improve  decarbonization  efforts. This comes at a time when states like California and Nevada—where tax credit incentives reward homeowners for going solar—face a unique issue: solar companies are having their energy needs exceeded by an excess of solar installations. 

In India, Adani Green Energy commissioned 1 gigawatt (GW) of solar power at the Khavda solar PV park in the state of Gujarat—a crucial step on its journey to building 30GW of capacity. 2 Meanwhile, UK-based Lightsource is developing a 560 MW solar PV park in Greece which will become the second-largest solar park in Europe, a title that is currently held by Witnitz solar park in eastern Germany. 3

Solar-powered refrigerators are helping to fight malaria outbreaks in Africa by storing vaccines at a safe temperature. 4 In Japan, plans are underway to beam solar energy straight from space down to Earth by 2025. 5 These innovations are made possible by the shrinking cost of solar power, which has dropped by 90% in the last decade, and developments in energy storage systems. 6

Improve your asset management strategy and optimize asset performance with a full suite of applications for operations and HSE tools for the utilities and energy industry.

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Renewable energy is energy generated from natural sources that are replenished faster than they are used.

Discover the types of renewable energy sources available to reduce your carbon footprint and environmental impact.

Thermal energy refers to energy within a system that’s created by the random motion of molecules and atoms.

Climate change refers to global warming, the documented global temperature increase of the Earth’s surface since the late 1800s.

The next generation of clean energy requires innovative technology to improve energy efficiency and power generation.

Sustainable technology describes technology created in consideration of environmental, social and economic factors.

IBM Environmental Intelligence Suite is a SaaS platform used to monitor, predict and respond to weather and climate impact. It includes geospatial and weather data APIs and optional add-ons with industry-specific environmental models—so your business can anticipate disruptive environmental conditions, proactively manage risk and build more sustainable operations.

1.  Solar PV  (link resides outside ibm.com), International Energy Agency, 11 July 2023

2.  Adani commissions 1GW of at Khavda PV park, world’s ‘largest’ solar project (link resides outside ibm.com), PV Tech, 12 March 2024

3.  UK-based Lightsource bp to build Europe’s second-biggest solar park in Greece (link resides outside ibm.com), Balkan Green Energy News, 29 April, 2024

4.  Malaria vaccine rollout shines light on value of renewable power (link resides outside ibm.com), Reuters, Payton, 2 April 2024

5.  Japan aims to beam solar power from space by 2025 (link resides outside ibm.com), The Independent, Cuthbertson, 30 May 2023

6.  Fossil fuels ‘becoming obsolete’ as solar panel prices plummet  (link resides outside ibm.com), The Independent, Cuthbertson, 27 September 2023

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AP®︎/College Environmental science

Course: ap®︎/college environmental science   >   unit 5.

• Renewable and nonrenewable energy resources

Renewable and nonrenewable energy sources

• Global energy use
• Intro to energy resources and consumption
• Nonrenewable energy sources are those that are consumed faster than they can be replaced. Nonrenewable energy sources include nuclear energy as well as fossil fuels such as coal, crude oil, and natural gas. These energy sources have a finite supply, and often emit harmful pollutants into the environment.
• Renewable energy sources are those that are naturally replenished on a relatively short timescale. Renewable energy sources include solar, wind, hydroelectric, and geothermal energy. They also include biomass and hydrogen fuels. These energy sources are sustainable and generate fewer greenhouse gas emissions than fossil fuels.

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'Sun is the ultimate source of energy.' Comment

The sun is the ultimate source of almost all kinds of energy on earth, either directly or indirectly. fossil fuels (coal, oil and gas) are the transformed forms of plants (and animals) which once lived on the earth and grew capturing the energy of the sun. biomass is a product of photosynthesis where the sun has the major role. solar energy is increasing becoming an important source of renewable energy . hydro-electricity depends upon the water cycle which again is dependent on solar radiation. similarly, wind energy , tidal power, wave power all, in some way or other, and depend on the sun. the sun is an extremely hot mass of gas, where continuous thermo-nuclear reaction is taking place producing enormous quantities of heat and light. the sun radiates energy in the form of heat and light in all directions. only a very small part of this energy is intercepted by our planet earth..

Why is sun considered to be ultimate source of energy?

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Solar Storm Intensifies, Filling Skies With Northern Lights

Officials warned of potential blackouts or interference with navigation and communication systems this weekend, as well as auroras as far south as Southern California or Texas.

By Katrina Miller and Judson Jones

Katrina Miller reports on space and astronomy and Judson Jones is a meteorologist.

A dramatic blast from the sun set off the highest-level geomagnetic storm in Earth’s atmosphere on Friday that is expected to make the northern lights visible as far south as Florida and Southern California and could interfere with power grids, communications and navigations system.

It is the strongest such storm to reach Earth since Halloween of 2003. That one was strong enough to create power outages in Sweden and damage transformers in South Africa.

The effects could continue through the weekend as a steady stream of emissions from the sun continues to bombard the planet’s magnetic field.

The solar activity is so powerful that the National Oceanic and Atmospheric Administration, which monitors space weather, issued an unusual storm watch for the first time in 19 years, which was then upgraded to a warning. The agency began observing outbursts on the sun’s surface on Wednesday, with at least five heading in the direction of Earth.

“What we’re expecting over the next couple of days should be more significant than what we’ve seen certainly so far,” Mike Bettwy, the operations chief at NOAA’s Space Weather Prediction Center, said at a news conference on Friday morning.

For people in many places, the most visible part of the storm will be the northern lights, known also as auroras. But authorities and companies will also be on the lookout for the event’s effects on infrastructure, like global positioning systems, radio communications and even electrical power.

While the northern lights are most often seen in higher latitudes closer to the North Pole, people in many more parts of the world are already getting a show this weekend that could last through the early part of next week.

As Friday turned to Saturday in Europe, people across the continent described skies hued in a mottling of colors.

Alfredo Carpineti , an astrophysicist, journalist and author in North London, saw them with his husband from the rooftop of their apartment building.

“It is incredible to be able to see the aurora directly from one’s own backyard,” he said. “I was hoping to maybe catch a glimpse of green on the horizon, but it was all across the sky in both green and purple.”

Here’s what you need to know about this weekend’s solar event.

How will the storm affect people on Earth?

A geomagnetic storm watch or warning indicates that space weather may affect critical infrastructure on or orbiting near Earth. It may introduce additional current into systems, which could damage pipelines, railroad tracks and power lines.

According to Joe Llama, an astronomer at Lowell Observatory, communications that rely on high frequency radio waves, such as ham radio and commercial aviation , are most likely to suffer. That means it is unlikely that your cellphone or car radio, which depend on much higher frequency radio waves, will conk out.

Still, it is possible for blackouts to occur. As with any power outage, you can prepare by keeping your devices charged and having access to backup batteries, generators and radio.

The most notable solar storm recorded in history occurred in 1859. Known as the Carrington Event, it lasted for nearly a week, creating aurora that stretched down to Hawaii and Central America and impacting hundreds of thousands of miles of telegraph lines.

But that was technology of the 19th century, used before scientists fully understood how solar activity disrupted Earth’s atmosphere and communication systems.

“That was an extreme level event,” said Shawn Dahl, a forecaster at NOAA’s Space Weather Prediction Center. “We are not anticipating that.”

Unlike tornado watches and warnings, the target audience for NOAA’s announcements is not the public.

“For most people here on planet Earth, they won’t have to do anything,” said Rob Steenburgh, a space scientist at NOAA’s Space Weather Prediction Center.

The goal of the announcements is to give agencies and companies that operate this infrastructure time to put protection measures in place to mitigate any effects.

“If everything is working like it should, the grid will be stable and they’ll be able to go about their daily lives,” Mr. Steenburgh said.

Will I be able to see the northern lights?

It is possible that the northern lights may grace the skies this week over places that don’t usually see them. The best visibility is outside the bright lights of cities.

Clouds or stormy weather could pose a problem in some places. But if the skies are clear, even well south of where the aurora is forecast to take place, snap a picture or record a video with your cellphone. The sensor on the camera is more sensitive to the wavelengths produced by the aurora and may produce an image you can’t see with the naked eye.

Another opportunity could be viewing sunspots during the daytime, if your skies are clear. As always, do not look directly at the sun without protection. But if you still have your eclipse glasses lying around from the April 8 event, you may try to use them to try to spot the cluster of sunspots causing the activity.

How strong is the current geomagnetic storm?

Giant explosions on the surface of the sun, known as coronal mass ejections, send streams of energetic particles into space. But the sun is large, and such outbursts may not cross our planet as it travels around the star. But when these particles create a disturbance in Earth’s magnetic field, it is known as a geomagnetic storm.

NOAA classifies these storms on a “G” scale of 1 to 5, with G1 being minor and G5 being extreme. The most extreme storms can cause widespread blackouts and damage to infrastructure on Earth. Satellites may also have trouble orienting themselves or sending or receiving information during these events.

The current storm is classified as G5, or “extreme.” It is caused by a cluster of sunspots — dark, cool regions on the solar surface — that is about 16 times the diameter of Earth. The cluster is flaring and ejecting material every six to 12 hours.

“We anticipate that we’re going to get one shock after another through the weekend,” said Brent Gordon, chief of the space weather services branch at NOAA’s Space Weather Prediction Center.

Why is this happening now?

The sun’s activity ebbs and flows on an 11-year cycle, and right now, it is approaching a solar maximum. Three other severe geomagnetic storms have been observed so far in the current activity cycle, which began in December 2019, but none were predicted to cause effects strong enough on Earth to warrant a watch or warning announcement.

The cluster of sunspots generating the current storm is the largest seen in this solar cycle, NOAA officials said. They added that the activity in this cycle has outperformed initial predictions .

More flares and expulsions from this cluster are expected, but because of the sun’s rotation the cluster will be oriented in a position less likely to affect Earth. In the coming weeks, the sunspots may appear again on the left side of the sun, but it is difficult for scientists to predict whether this will cause another bout of activity.

“Usually, these don’t come around packing as much of a punch as they did originally,” Mr. Dahl said. “But time will tell on that.”

Jonathan O’Callaghan contributed reporting from London.

An earlier version of this article misstated the radio frequencies used by cellphones and car radios. They are higher frequencies, not low.

How we handle corrections

Katrina Miller is a science reporting fellow for The Times. She recently earned her Ph.D. in particle physics from the University of Chicago. More about Katrina Miller

Judson Jones is a meteorologist and reporter for The Times who forecasts and covers extreme weather. More about Judson Jones

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A dramatic blast from the sun  set off the highest-level geomagnetic storm in Earth’s atmosphere, making the northern lights visible around the world .

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What causes the different colours of the aurora? An expert explains the electric rainbow

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Last week, a huge solar flare sent a wave of energetic particles from the Sun surging out through space. Over the weekend, the wave reached Earth, and people around the world enjoyed the sight of unusually vivid aurora in both hemispheres.

While the aurora is normally only visible close to the poles, this weekend it was spotted as far south as Hawaii in the northern hemisphere, and as far north as Mackay in the south.

This spectacular spike in auroral activity appears to have ended, but don’t worry if you missed out. The Sun is approaching the peak of its 11-year sunspot cycle , and periods of intense aurora are likely to return over the next year or so.

If you saw the aurora, or any of the photos, you might be wondering what exactly was going on. What makes the glow, and the different colours? The answer is all about atoms, how they get excited – and how they relax.

When electrons meet the atmosphere

The auroras are caused by charged subatomic particles (mostly electrons) smashing into Earth’s atmosphere. These are emitted from the Sun all the time, but there are more during times of greater solar activity.

Most of our atmosphere is protected from the influx of charged particles by Earth’s magnetic field. But near the poles, they can sneak in and wreak havoc.

Earth’s atmosphere is about 20% oxygen and 80% nitrogen, with some trace amounts of other things like water, carbon dioxide (0.04%) and argon.

When high-speed electrons smash into oxygen molecules in the upper atmosphere, they split the oxygen molecules (O₂) into individual atoms. Ultraviolet light from the Sun does this too, and the oxygen atoms generated can react with O₂ molecules to produce ozone (O₃), the molecule that protects us from harmful UV radiation.

But, in the case of the aurora, the oxygen atoms generated are in an excited state. This means the atoms’ electrons are arranged in an unstable way that can “relax” by giving off energy in the form of light.

What makes the green light?

As you see in fireworks, atoms of different elements produce different colours of light when they are energised.

Copper atoms give a blue light, barium is green, and sodium atoms produce a yellow–orange colour that you may also have seen in older street lamps. These emissions are “allowed” by the rules of quantum mechanics, which means they happen very quickly.

When a sodium atom is in an excited state it only stays there for around 17 billionths of a second before firing out a yellow–orange photon.

But, in the aurora, many of the oxygen atoms are created in excited states with no “allowed” ways to relax by emitting light. Nevertheless, nature finds a way.

The green light that dominates the aurora is emitted by oxygen atoms relaxing from a state called “¹S” to a state called “¹D”. This is a relatively slow process, which on average takes almost a whole second.

In fact, this transition is so slow it won’t usually happen at the kind of air pressure we see at ground level, because the excited atom will have lost energy by bumping into another atom before it has a chance to send out a lovely green photon. But in the atmosphere’s upper reaches, where there is lower air pressure and therefore fewer oxygen molecules, they have more time before bumping into one another and therefore have a chance to release a photon.

For this reason, it took scientists a long time to figure out that the green light of the aurora was coming from oxygen atoms. The yellow–orange glow of sodium was known in the 1860s, but it wasn’t until the 1920s that Canadian scientists figured out the auroral green was due to oxygen.

What makes the red light?

The green light comes from a so-called “forbidden” transition, which happens when an electron in the oxygen atom executes an unlikely leap from one orbital pattern to another. (Forbidden transitions are much less probable than allowed ones, which means they take longer to occur.)

However, even after emitting that green photon, the oxygen atom finds itself in yet another excited state with no allowed relaxation. The only escape is via another forbidden transition, from the ¹D to the ³P state – which emits red light.

This transition is even more forbidden, so to speak, and the ¹D state has to survive for about about two minutes before it can finally break the rules and give off red light. Because it takes so long, the red light only appears at high altitudes, where the collisions with other atoms and molecules are scarce.

Also, because there is such a small amount of oxygen up there, the red light tends to appear only in intense auroras – like the ones we have just had.

This is why the red light appears above the green. While they both originate in forbidden relaxations of oxygen atoms, the red light is emitted much more slowly and has a higher chance of being extinguished by collisions with other atoms at lower altitudes.

Other colours, and why cameras see them better

While green is the most common colour to see in the aurora, and red the second most common, there are also other colours. In particular, ionised nitrogen molecules (N₂⁺, which are missing one electron and have a positive electrical charge), can emit blue and red light. This can produce a magenta hue at low altitudes.

All these colours are visible to the naked eye if the aurora is bright enough. However, they show up with more intensity in the camera lens.

There are two reasons for this. First, cameras have the benefit of a long exposure, which means they can spend more time collecting light to produce an image than our eyes can. As a result, they can make a picture in dimmer conditions.

The second is that the colour sensors in our eyes don’t work very well in the dark – so we tend to see in black and white in low light conditions. Cameras don’t have this limitation.

Not to worry, though. When the aurora is bright enough, the colours are clearly visible to the naked eye.

Read more: What are auroras, and why do they come in different shapes and colours? Two experts explain

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• Aurora borealis
• Aurora Australis

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The stormy sun erupts with its biggest solar flare yet from a massive sunspot — and it's still crackling (video)

The colossal X5.8-class solar flare was followed by yet another X1.5 solar flare, the strongest types of flares there are.

Just when we thought we'd seen the most powerful flares from a colossal sunspot, the sun unleashed its strongest eruption of the weekend yet, triggering a radio blackout even as the star continues to crackle with solar storms. 

According to NOAA's Space Weather Prediction Center (SWPC), the dynamic solar flare occurred late Saturday (May 10) from an active sunspot region called AR3664. It peaked at 9:23 p.m. EDT (0123 May 11 GMT), registering as a massive X5.8 class flare, SWPC officials said . As a result, parts of some of the Earth's sunlit side had temporary or complete loss of high frequency (HF) radio signals. 

The sun , proving that it wasn't done yet, also fired off a powerful X1.5 solar flare at 7:44 a.m. EDT (1144 GMT), NASA officials said. X-class flares are the strongest types of solar eruptions from the sun, and while flares can last anywhere from a few minutes to hours, to get these high magnitudes aren't as common. Yet, the sun has fired off a series of powerful flares this week that have supercharged Earth's northern lights displays .

— Behemoth sunspot AR3664 unleashes its biggest solar flare yet

— Sun explodes in a flurry of powerful solar flares from hyperactive sunspots (video)

— Wild solar weather is causing satellites to fall. It's going to get worse.  

"Solar flares are powerful bursts of energy," NASA wrote in a statement on the flares. "Flares and solar eruptions can impact radio communications, electric power grids, navigation signals, and pose risks to spacecraft and astronauts."

According to the recent NOAA SWPC discussion , region 3664 has the potential to stay busy through Monday (May 13). High to very high levels of solar activity are expected with an increased likelihood for more flares in the top two classes, M and X. The active region is a massive sunspot complex about 17 times the width of Earth , NOAA SWPC officials said.

Related: Jaw-dropping northern lights from massive solar flares amaze skywatchers

Sony A7III was $1799.99 , now $1498 Sony’s third incarnation of the game-changing Sony A7 camera, the Sony A7III is lightweight yet packs a punch. With 4K HDR video, this camera is often used to capture videos of the Northern Lights. Right now, you can find it on sale for 17% off at Amazon. Check out our Sony A7III review .

Scientists have also noted that there was a coronal mass ejection (CME), a large expulsion of plasma and magnetic field, from the main eruption, which they are analyzing and modeling. This could bring additional impacts to Earth in the coming days including issues with power grids, telecommunication networks, and to satellites in orbit as well as another opportunity for a charged-up view of the northern lights for some locations! 

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Editor's note: If you capture a stunning photo or video of the northern lights (or southern lights!) and want to share them with Space.com for a possible story, send images, comments on the view and your location, as well as use permissions to [email protected] .

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Meredith is a regional Murrow award-winning Certified Broadcast Meteorologist and science/space correspondent. She most recently was a Freelance Meteorologist for NY 1 in New York City & the 19 First Alert Weather Team in Cleveland. A self-described "Rocket Girl," Meredith's personal and professional work has drawn recognition over the last decade, including the inaugural Valparaiso University Alumni Association First Decade Achievement Award, two special reports in News 12's Climate Special "Saving Our Shores" that won a Regional Edward R. Murrow Award, multiple Fair Media Council Folio & Press Club of Long Island awards for meteorology & reporting, and a Long Island Business News & NYC TV Week "40 Under 40" Award.

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Sun emits its largest X-class flare of the solar cycle as officials warn bursts from massive sunspot "not done yet"

By Li Cohen

May 14, 2024 / 4:13 PM EDT / CBS News

The giant solar explosions of energy and light aren't over yet. Officials said on Tuesday that the sun just emitted another major solar flare – and that it's the strongest one so far in the current solar cycle. 

The latest flare peaked just before 1 p.m. ET, NOAA's Space Weather Prediction Center said, with an X-class rating of X8.7. X-class solar flares are the strongest of solar flares, which are described by NASA as " giant explosions on the sun that send energy, light and high speed particles into space." The center said the flare was an R3 or "strong" flare, meaning it could have caused wide area blackouts of high-frequency radio communications for about an hour on the sunlit side of Earth. It also may have caused low-frequency navigation signal issues for the same period of time. 

"Flares of this magnitude are not frequent," the center said in its update, also posting on social media, "Region 3664 not done yet!"

The flare came out of the sunspot dubbed 3664. That spot, combined with region 3663, makes up a cluster "much larger than Earth," NOAA said last week. And as of last Thursday, 3664 was only continuing "to grow and increase in magnetic complexity and has evolved into a higher threat of increased solar flare risk."

Two other flares – rated X1.7 and X1.2 – also erupted shortly before , although they were also not anticipated to be linked to any major impacts on Earth.

Despite the intensity of the flare, officials said there is not yet concern of a coronal mass ejection, or large burst of solar plasma and magnetic field. Those CMEs are what lead to geomagnetic storms like the rare extreme storm that occurred over the weekend, sending the northern lights to far lower latitudes than normal and causing chaos for GPS systems that farmers rely on at the height of planting season. 

"Due to its location, any CME associated with this flare will likely not have any geomagnetic impacts on Earth," the Space Weather Prediction Center said. 

Earth is currently in Solar Cycle 25 , which began in 2020. The last cycle maintained an average length of 11 years and was the weakest solar cycle to occur in a century, the National Weather Service said. Although the current cycle has been forecast to be fairly weak and similar to the one prior, NOAA officials saw "a steady increase in sunspot activity" from the get-go.

"While we are not predicting a particularly active Solar Cycle 25, violent eruptions from the Sun can occur at any time," Doug Biesecker, a solar physicist at NOAA's Space Weather Prediction Center, said in 2020. 

• National Oceanic and Atmospheric Administration

Li Cohen is a social media producer and trending content writer for CBS News.

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