Stars are giant nuclear reactors


Stars are giant nuclear reactors
No-one know how many stars there are.Star exist in group called Galaxies.Our own star, the Sun, is part of a galaxies called the Milkey way.The milkey way contains about100 thousand millions stars.At the present time,astronomers are aware of more than 100 thousand million galaxies.So the total number of stars in the universe is enormous.

Because most stars are very far away, even the best telescopes show them as just spots of light.But our own sun is mucher closer.Astronomers can study the sun to find out about what happens inside stars.

The sun is made up of gas.Most of the gas is hydrogen.The temperature at the surface of the sun is about 6000 degree celsius.Deep inside the sun, the temperature is Stars are giant nuclear reactors16000000 degree celcius.Inside the sun,the nuclei of hydrogen atoms fuse together to form helium atoms.This is called nuclear fusion.It is release enormous amounts of energy.Human have also made nuclear fusion happen,using hydrogen bombs.Scientist are now trying to make nuclear fusion happen in a controlled way,so that the energy released can be used to electricity.

The energy released from the sun is given off as electromagnetic radiation.All kinds of electromagnetic radiation are released,ranging from X rays to radio waves.We are most aware of the visible light emitted from the sun,and the infrared radiation,which warms the earth.But the sun and other stars can also be studied by observing the other kinds of radiation which they emit,especially radio waves


0 comments:

Post a Comment

Twitter Delicious Facebook Digg Favorites More