Literally at the center of our galaxy lies a reason for our existence: the sun. The sun has often been personified in mythology as a life-bringer. In ancient Egypt, the sun god Ra was the father of the Egyptian civilization, particularly the pharaohs, giving the royal family the divine right to rule. Apollo and Helios in Greek mythology are both personified as light deities connected to the sun and both established and maintained order in the universe with their many powers. Aztec legends attribute the sun to many gods, each bringing gifts to mankind that improve their lives by keeping them fed and warm and protecting them from their enemies. In short, the importance of this glowing orb that travels the sky has always been acknowledged and respected. With the advances of modern science and astronomy, we have been able to become even more acquainted with the facts and science behind the workings of this fantastically complex and important celestial body.

What is the sun?
The sun is classified as a G2 type V yellow star. "G2" refers to the elemental signature that the sun emits (mainly that it emits more calcium and magnesium than other stars); "type V" tells us that the sun is classified as a dwarf star, which means relative to other stars, our sun is a smaller size than giant stars like Betelgeuse. That doesn't mean our sun is tiny: In fact, it's 875,000 miles across and could fit 1,600 Saturns inside of it! The classification as a yellow star tells us that our Sun is in the medium to low range when it comes to star temperature.

How was it formed?
The sun was formed from a large cloud of space dust and gases, which gravity acted upon to draw it together. After a few million years, the force of gravity pulling all of these bits together brought about a rotational force that helped concentrate all of this swirling matter toward its center, causing a gradual increase in temperature. As more matter was pulled in by gravity, energy output continued to increase until there was enough energy to cause a nuclear reaction. Once this explosion had occurred, our sun was born as a new star.

What is it made of?
Our sun is actually a big, burning ball of plasma. The most prominent gas is hydrogen, which makes up the majority of the sun's composition (around 70%). Helium is the next plentiful gas on the sun and comprises around 28% of the sun's gases. The remaining small percentage is filled by gases like neon and particulates of iron, silicon, and other elements.

How does it create energy?
Due to the high temperatures in the center of the sun, the hydrogen nearest to this innermost core is so hot that it actually breaks down into smaller particles, protons and electrons, and those particles fuse with particles of helium. As these hydrogen molecules are being toasted to bits and then fused with other atoms, they release massive amounts of energy, which is always trying to move outward. This is called nuclear fusion, which is how the sun creates most of its energy.

How does it provide energy to the Earth?
The sun emits rays that travel through space to the Earth. Some of these light rays we can see, but others, like X-rays, we can't see. The type of energy the Earth receives from the sun is called radiant energy. When these rays of energy enter the atmosphere, some bounce off the clouds and are sent back out into space, but most are absorbed by the Earth and transformed into heat. This heat warms the planet to keep it from getting too cold and warms the water on Earth, evaporating it and starting the water cycle. The energy we receive from the Sun also enables our plant life to create food for itself, which helps to generate oxygen for us and stabilizes our food chain.

What are the layers of the solar atmosphere?
Like Earth, the sun is made up of many layers. The innermost layer is called the core, and it is a dense, solid, and extremely hot orb of metal (27,000,000 degrees Farenheit!). Right outside the core is the solar envelope, which puts pressure on the core and maintains the core's high temperature. Next is the photosphere: This layer is what we're seeing when the sun shines, and this is also the layer we can observe sun spots on - these are cooler areas on the sun's surface. After that is the chromosphere, a layer only visible during a solar eclipse; it produces a red glow around the sun, caused by the high concentration of hydrogen. The corona is the final and outermost layer of the sun, and like the chromosphere, it is only visible during a solar eclipse.

Does the sun rotate?
Yes! The sun isn't just hanging out there; it does actually rotate on its own axis. The sun turns a full rotation on its axis once every 26 days. Incredibly, different parts of the sun rotate at different rates. The fastest rotation of the sun occurs at the sun's equator, and at each of the poles, the sun's rotation is actually slower: It takes 30 days for the poles to fully rotate. This type of rotation is called differential rotation.

What are solar flares?
A solar flare is a reaction that occurs as the result of a buildup of magnetic energy in the solar atmosphere. When this energy is suddenly released, there is a quick flash of brightness, which we define as a solar flare. Solar flares are set off when large magnetic loops on the sun called prominences come into contact with each other. A solar flare releases a huge amount of energy; average solar flares contain energy bursts nearly ten million times greater than those caused by volcanic activity on earth. Due to the sun's brightness, it's very difficult to see solar flares even with a telescope (and you should never look directly at the sun, as you can damage your eyes). To detect a solar flare, scientists use special equipment to measure emissions of radiation, which tell them when a solar flare is occurring and classify it based on the concentration of the X-ray wavelengths it emits.

What is a solar eclipse?
A solar eclipse is a celestial phenomenon in which the moon comes between Earth and the sun. There are two types of eclipses. The first, a total eclipse, means that the sun is completely blocked by the moon for a few moments; the second type, a partial eclipse, is when the sun is not fully blotted out by the moon. Eclipses can only occur during the new moon phase of our moon, and they often do not occur every time there is a new moon because of the different angles at which Earth, the moon and the sun all rotate. But eclipses do occur more than you might think; there are at least two solar eclipses a year, though usually, they are only partial eclipses.
Article written by Lexi Westingate
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