1. The Sun
The sun is mostly hydrogen with about 10% helium and other elements. The nuclear reaction in the core changes the hydrogen to helium and releases tremendous amounts of energy as light, heat, x-rays, and high speed particles. As this happens the constant churning of the gases causes an intense magnetic field and other effects. Sunspots, solar winds, prominences and flares are some of these effects.
We think of the Earth as a huge place. The diameter of the Sun is about 100 times wider than the Earth as can be seen in the diagram at left. Our Sun is an average size star but it has 98% of all the mass of the solar system. Some stars are as small as the Earth while others can be 500 times bigger than our Sun.Rocky Earth-like planets are really hard to find around other stars because they are lost in the glare of the star.
We can only see the outer layers of the sun during eclipses.
The picture above shows the corona. Not seen is the solar wind which also influences the Earth's magnetic field and auroras. The solar wind is predicted to extend more than 50 A.U. (50 times the distance from the sun to the Earth. One Astronomical Unit is 149,597,870 km.) which is a really huge distance.
The picture at right shows the corona. Not seen is the solar wind which also influences the Earth's magnetic field and auroras. The solar wind is predicted to extend more than 50 A.U. (50 times the distance from the sun to the Earth. One Astronomical Unit is 149,597,870 km.) which is a really huge distance.
Solar flares can sometimes leave the sun and zoom towards Earth. When the high speed particles from the sun contact the Earth's magnetic field it produces a lighting effect known as the aurora. Here it is seen from the Space Shuttle in orbit.
