|
The sun is the star at the center of the solar system. It formed about 5 billion years ago from a huge cloud of gas and dust. About 109 Earths would fit across the face of the sun! One large sunspot could hold several Earths. The sun\'s diameter is 864 thousand miles. Most of the mass in the solar system is in the sun (99%). The sun spins on its axis from left to right. It takes about 26 days for the sun to spin one time. The sun\'s outer atmosphere is called the corona. Its inner atmosphere is called the chromosphere. Below the photosphere are the convective zone, the radiative zone, and the core. The sun\'s core converts 700 million tons of hydrogen gas into 695 million tons of helium gas every second. The remaining 5 million tons of matter is converted to pure energy. That 5 million tons is about 600 times the amount of water flowing over Niagara Falls in one second. The temperature at the sun\'s core is 15 million degrees (K). Although sunspots are very hot, they are slightly cooler than the rest of the photosphere so they look darker. Sunspots have a dark center called the Umbra and a lighter ring around the outside called the Penumbra. It takes 50 million years for the energy formed deep inside the sun to reach Earth. Earth only gets one-billionth of the total energy produced by the sun. Light, traveling at 186 thousand miles per second, takes just over 8 minutes to reach Earth from the sun. Apollo was both the Greek and Roman god of the sun. He brought life-giving heat and light to Earth and was the patron god of musicians and poets.
Sunspots are slightly cooler than the rest of the sun\'s surface, which makes them look darker
Two large prominences arc away from the sun.
|
