1. Galaxy Clusters

2. Neighbors There are two close galaxies in the southern hemisphere.
kpc
1 - 2 billion stars
Gas bridge between
These are the Magellanic Clouds.
ESO

3. Satellite Galaxies
The Milky Way has 200 billion stars and a large gravitational force.
Smaller galaxies in orbit
There are 9 dwarf galaxies within 500,000 ly.

4. Sister Galaxy The nearest large galaxy is in Andromeda. M31
20% larger Milky Way
0.78 Mpc = 2.5 Mly
T. Van, earthsky.org
D. Locke, dl-digital.com

5. Local Group
Milky Way, M31, and the Triangulum Galaxy plus satellites make up the Local Group.
54 separate galaxies
Over 1 trillion stars
10 Mly = 3.1 Mpc across

6. Future Milky Way
The Milky Way and Andromeda galaxies orbit a common center of gravity.
Slowly pulled together by gravity
In about 4 billion years they will collide.
This will set off a round of new star formation.

7. Virgo Cluster The Virgo Cluster includes more than 2000 galaxies.
They all exert gravity on each other.
X-ray views show the collisions of gas and dust.
visible
x-ray

8. Supercluster The Local Group orbits the massive Virgo Cluster.
Many clusters make up the Virgo Supercluster.

9. Universe There are over 200 billion observable galaxies.
Sky Surveys put together composite images.
All superclusters are moving around a universal Great Attractor.
200 Mly = 60 Mpc

10. Structure
Computer simulations are used to model the evolution of galaxies in the universe.
Filaments
Voids