The Rhythmic Sky Page 21

7. Milky Way

Another feature in the sky, especially at very clear nights, is the Milky Way, a band of many stars. This is our galaxy in which the Sun with its planets is only a very minor and hardly significant object, one of about several hundred billion stars. That lane across the sky shows us the Galactic Plane, the disk of the Milky Way galaxy.

Some parts of the Milky Way appear dark, as if there are few stars in that region. This is only apparent, it is caused by large clouds of hydrogen and stellar dust, that block the visible light. In the southern hemisphere we can see the centre of our galaxy in the constellation of Sagittarius.

The galactic centre in the direction of Sagittarius.
The primary stars of Sagittarius are indicated in red.
Image Wikipedia



Artist reconstruction of the Milky Way galaxy,
based on what we have observed in many different wavelengths. Our Solar System is located somewhere in one of the outer spiral arms.
Image M. Garlick, APOD, NASA.