The Milky Way is the faint, hazy band of light that you can see stretching right across the night sky.
Looking through binoculars, you would see that the Milky Way is made up of countless stars.
A galaxy is a vast group of stars, and the Milky Way is the galaxy we live in.
There are billions of galaxies in space.
The Milky Way is 100,000 light-years across and 1000 light-years thick. It is made up of 100 billion stars.
All the stars are arranged in a spiral (like a giant Catherine wheel), with a bulge in the middle.
Our Sun is just one of the billions of stars on one arm of the spiral.
The Milky Way is whirling rapidly, spinning our Sun and all its other stars around at 100 million km/h. The Sun travels around the galaxy once every 200 million years – a journey of 100,000 light-years.
The huge bulge at the center of the Milky Way is about 20,000 light-years across and 3000 thick. It contains only very old stars and little dust or gas.
There may be a huge black hole in the very middle of the Milky Way.