Stars
Star Nurseries
Life of a star:
Stars start as dust and gas.
When a star is born the gas and dust come together to form a star cluster.
Gas forms into knots as gravity pulls it together.
As gas comes closer together it heats up.
Then the gas starts whirling around.
The protostar gives out jets of gas from its hole.
The gas particles join together in the hot center and finally the star begins to shine.
On a clear night people cannot see more than 2,000 stars.
Our sun is 93 million miles away.The next nearest star is 300,000 times farther than the sun.
There are 200 billion stars in the Milky Way.
About a third of the stars that we can see with our own eyes are double or triple stars, as can be seen by a telescope.
Stars are not shaped like stars. They are shaped like balls.
If a star gets too close to the black hole and interferes with its gravity the star would get sucked into the hole so that not even light could escape.
Stars the size of our sun will burn about 10,000 million years.
The life span of the stars varies. The smaller the star the longer it is going to burn.
Stars have a different brightness when they burn. The hotter the star, the brighter it shines.
Stars vary in color. The main colors are red, yellow, white and blue. Blue stars burn the hottest and red stars burn the coolest. Our sun is a yellow star.
There are two types of star clusters: the open clusters and the globular clusters. An open cluster is bright young stars which have just formed and are still relatively close together in space. A globular cluster is millions of stars grouped together which appear as very faint stars.
There are 4 types of galaxies: spiral galaxy, a barrel galaxy, an elliptical galaxy and an irregular galaxy. A spiral galaxy has a bright middle and two curving arms on its outside. A barrel galaxy has a middle with one arm at each end. An elliptical galaxy has old red stars in it with not much gas or dust. They vary in shape from circle to oval. An irregular galaxy is just clouds and stars and has no fixed shape.
Most astronomers believe the Milky Way (our galaxy) is a spiral, but some believe it is a barrel, spiral galaxy.
Check out the Constellations