The Milky Way
The Milky Way, as seen
from the Earth (AAO)
The Milky Way is a spiral galaxy, with a central bulge of intermediate
size. The disk is composed by 4 spiral arms, being the Sun placed between the
arm of Sagittarius and the arm of Perseus. The Milky Way has a diameter of 80 000
light years and an estimated amount of about 200 billion stars. The Sun travels
around the Milky Way once every 240 million years.
_