The Sun sustains all life on our planet


The Sun is at the center of our solar system. We've learned that the Sun is a huge ball of ionized gas. It's thought to be approximately 4.5 billion years old, and it is the star Earth revolves around. This star is the lifeblood of the Earth and supports all life on our planet. Without it, there would be no food or fossil fuels. This star that we depend on so much is the reason there are seasons on Earth, it also causes ocean currents and the weather patterns on the Earth.

Now that is massive

The mass of our star is over 300,000 times as massive as the Earth. It contains over 99% of the mass in the solar system. Intense gravitational attraction holds it together. Gravitational attraction causes the extremely high temperature and pressure inside the core. It is over 160 times as dense as water.

Going inside our star

The temperature inside the core is 16 million degrees Kelvin. That is hot enough for thermonuclear fusions reactions to occur. The energy that is released by these fusions reactions keeps our solar system's star from collapsing and helps it stay in gaseous form. The amount of energy produced is 383 billion trillion kilowatts. That would be like 100 billion tons of dynamite exploding every second!

The interior of our solar system's star has two distinctive areas apart of the solar core. A radiative area and a convective area. After the solar core, is the radiative zone. Then on through to the convective zone. The temperature gradually decreases in these zones from 8 million degrees Kelvin to 7000 degrees Kelvin.

The photosphere

The surface of our star is called the photosphere. It is 500 kilometers thick and it is also where most of the light and radiation escape. It is the place where sun spots take place. The chromosphere is next. It looks like a reddish rim and it can be seen during solar eclipses. Next comes the corona and it is known as the solar wind.

Watch this video of the surface of our Sun

Here's another video about Sun storms

More Sun resources

What are solar eclipses?

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