Cassiopeia Project - Milky Way

An educational video from the Cassiopeia Project website

Transcript:

Twelve and a half Billion Years ago, the universe was littered with the remains of
first generation stars, and billions of second generation stars were born from
these clouds.
Small groups of these new stars were drawn to each other gravitationally and
merged to form ever larger and larger groups. Our own galaxy, the Milky Way, is
an example of a spiral galaxy born in this early era.,
Today it contains about 200 billion stars, and it is still growing as it absorbs small
neighboring clusters of stars.
The center of our galaxy is in the direction of the constellation Sagittarius, and
like most large galaxies, there is a monstrous black hole at the center.
The disk of our galaxy is about 100,000 light years across and on average is only
about 12,000 light years thick.
Our own sun is a third generation star and is located about two thirds of the way
out on the spiral arm named Orion. We are about 26,000 light years from the
center.
The Milky Way is a member of a group of 20 or 30 galaxies and star clusters
called our local group. The largest galaxy in this group is our sister spiral galaxy,
Andromeda.