This is our galaxy, the "Milky Way", viewed from above.
The Milky Way is a large spiral galaxy containing roughly 100 billion stars disposed in the form of a disk, with several spiral arms coiling around a central bulge.
The diameter of the disk is about 100 000 light years and the Sun is located about 30 000 light years from the Milky Way’s nucleus on the Orion arm, at the center of the little red grid.
This grid delimits a square area of about 1500 x 1500 light years, magnified in the map below.
This is the galactic environment within 1500 light years from Sol, rich of gas clouds.
Note the "
Dumbbell nebula" on the top left,
Polaris on the bottom left,
the Pleiades and
Betelgeuse below the central red grid,
Rigel (Beta Orionis) on the bottom right,
Hadar (Beta Centauri) on the top right,
Antares above the central red grid.
The red grid is a square area of about 400x400 light years, magnified in the map below, with our Sun at the center.
This image represents the solar neighborhood. Our solar system is located in an unusual region of space called the "Local Bubble" because the ISM (InterStellar Medium) in this area is much less dense than the ISM surrounding it.
Scientists believe that this bubble may have been created by a supernova explosion.
http://fi.wikipedia.org/wiki/Paikallinen_kuuma_kupla
