Milky Way Galaxy
Our sun is part of a gigantic cloud of stars called the Milky Way
Galaxy.
The Milky Way
On a clear summer night you can sometimes see a bright haze in part of
the sky. This haze is called the Milky Way. It looks like a gigantic
cloud of stars, close together. Actually, the stars are many trillions
of miles (kilometers) apart. But there are so many of them, they look
like a glowing cloud.
The Milky Way is part of an even bigger cloud of stars. This star cloud
is shaped like a pancake with a bulge in the middle. It contains more
than 100 billion
stars. This huge mass of stars is called a galaxy—the Milky Way
Galaxy.
Our sun is one of the stars in this galaxy. The sun is far out near the
pancake’s edge. We cannot see all the way to the bulging center. Clouds
of gas and dust, like thick fog, block our view.
Just as the earth moves around the sun, the sun and other stars move
around the center of the galaxy. But the galaxy is so enormous, and the
sun is so far from its center, that it takes the sun about 225 million
years to go all the way around!
the Milky Way
The glowing cloud we call the Milky Way is made up of billions of
stars that are trillions of miles (kilometers) apart. The white line
in the photograph is the track of an artificial satellite circling the
earth.
