１２ Life of Stars【What is the Universe？】Dialogue with the Universe
・Big star burns out faster than small one.
（Since stars have a
limited supply of hydrogen in their cores, they have a limited lifetime as main
sequence stars. This lifetime is proportional to f M / L, where f is the
fraction of the total mass of the star, M, available for nuclear burning in the
core and L is the average luminosity of the star during its main sequence
lifetime. Because of the strong dependence of luminosity on mass, stellar
lifetimes depend sensitively on mass.）[1]
•
The lifetime of the sun is about 100 million years. The life of stars of 10
times weight of the sun is from 1 / 1000 to 1 / 100.
・The Sun formed about 4.6 billion years ago. It will
exit the main sequence in approximately 5 billion
years and start to turn into a red giant. [2]
【Refereces】
1.
The Life and Death of
Stars NASA
2.
Wikipedia：Sun
0 件のコメント:
コメントを投稿