Environment

Amazing Facts About the Sun

How much do you know about the Sun, the source for all life on Earth?

10. The sun is mostly made of hydrogen and helium.

The sun is primarily made up of two gases - hydrogen and helium. Hydrogen makes up approximately three-quarters of the mass of the sun while helium gas takes up the rest. The sun also contains negligible amounts of oxygen, silicon, neon, carbon, magnesium, nitrogen, sulfur, and iron gases. In its composition, the sun needs to satisfy two critical conditions. The first one is that it has to occupy the generally accepted range of its mass which is 1.4 x 1029 kg and 3.0 x 1032 kg. The second requirement is that the sun should exhibit nuclear fusion.

9. The temperature of the sun's surface? 10,000 degrees fahrenheit.

The sun’s temperature is mainly influenced by its gravitational attraction. Temperatures are highest at the core of the sun where they can go up to 27 million degrees Fahrenheit. This temperature is a result of nuclear fusion whereby hydrogen atoms fuse to form Helium. The fusion produces large amounts of energy which radiate outward to the surface of the sun. From the core of the sun, energy moves to the radiative zone where it stays for approximately 1 million years then moves to the convective zone. Temperatures at the convective zone drop to about 3.5 million degrees Fahrenheit. The sun’s energy then moves to the photosphere where the temperatures reduce further to about 10,000 degrees Fahrenheit. At this point, the sun’s radiation becomes visible light.

8. The sun is over 4.5 billion years old.

The sun, being a star, has a life cycle which is dependent on its mass. Accordingly, the sun is estimated to be 4,600,000,000 years old. It has converted about half of its hydrogen into helium and will need about 5 billion more years to burn the rest. Hence the sun will exist 5 billion years to come. Astronomers determine the age of the sun through a process called radiometric dating.

7. And it has not changed in 4 billion years.

The sun has not changed so far as it has been in its main sequence stage for most of the time. The main sequence stage is characterized by nuclear fusion which produces energy and light to the earth. The sun will not change for the next 5 billion years. After this long duration of time, hydrogen and helium supply will be depleted and the sun will enter the Red Giant stage. Here the core of the sun will heat up and get denser leading to an increase in the size of the sun so much that it will explode.

6. If you stare at the sun for too long, you can burn your retinas.

Staring at the sun for too long without using binoculars fitted with filters is harmful to the retina. The sun’s rays have a component known as the Ultra Violent (UV) radiation. The UV radiation is classified into three namely UV-A, UV-C, and UV-B. The UV-C is not harmful to the eyes. However, UV-A and UV-B negatively affect the eyes in the short and long run. Short term exposure to the UV-radiation causes photokeratitis that is commonly called “sunburn of the eye.” However, the long term effect is that the eye develops cataracts later in life. Eventually, the human eye retina may burn.

5. The sun is actually white - not yellow.

The sun is made up of colors as plentiful as those that form the rainbow. When all colors are put together the resultant color is white. Hence, this is the sun’s real color and photos of the sun taken by astronauts clearly indicate this. However, when observed from the earth, the sun’s color ranges from whitish-yellow to red. The reason for this is that the earth scatters the colors with higher wavelengths such as red, orange and yellow and not those with shorter wavelengths. As such it is these wavelengths that make us describe the sun as red, orange or yellow.

4. The sun contains 99% of the Solar System's mass.

The sun is the most massive and largest object in the solar system. Having occupied 99% of the Solar System, the other 1% is largely made up of the giant planets such as Jupiter and Saturn. The sun is approximately 1,989,100,000,000,000,000,000 billion kg. 70% of the its mass is Hydrogen gas while 28% is Helim. The 2% of the sun’s mass represents the other gases. In comparison to the mass of Earth, the sun’s mass is equal to 333,060 Earths. However, studies show the sun is slowly losing its mass over time. It is doing so by converting its mass into energy and light, as well as through its solar wind. Compared to other stars, there are stars which are almost 100 times as massive as the sun. For instance, the largest star is VY Canis Majoris and its radius is 1800-2100 times that of the sun’s radius. The mass of the sun can be measured using the Newton’s laws of motion and the law of gravity.

3. In fact, the Earth could fit inside the Sun 1 million times.

The diameter of the earth is 12,756 km while that of sun’s diameter is 1,392,000 km. Hence the diameter of the sun is 109 times that of the earth. Therefore if the earth is squashed inside the sun, 1.3 million earths will fit into it. However, if the earth’s spherical shape is maintained then there will be 960,000 earths fitting into the sun.

2. Sometimes, it may appear as if there is more than one sun in the sky, thanks to sun dogs.

Also known as parhelia, sun dogs are “mock-suns” that usually appear as bright spots on both sides of the sun. Sun dogs are members of the halo family. They are formed when light interacts with ice crystals in the air and appear at 22 ͦ to the left and right of the sun. They are most conspicuous when the Sun is close to the horizon.

1. Scientists say that eventually, in a long time from now, the sun will consume the Earth.

5 billion years to come the sun will increase in size, encompassing the orbits of Mercury, Venus, and Earth. If the sun does not consume the earth then, the new earth’s proximity to the sun will make it impossible for it to support any life in it. If the earth is engulfed by the sun in its red giant stage, it will collide with gas particles. Consequently, the earth’s orbit will decay and spiral inward.

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