ESA Science & Technology03-Aug-2005 11:13:30
 

Galaxies and the Expanding Universe

Local Group

Gravity draws galaxies together into groups known as galactic clusters, which orbit around their centre. As well as the stars, gas and dust that make up the galaxies, the galactic cluster is embedded in vast clouds of extremely hot gas, filling the spaces between the galaxies. However, scientists have calculated that the galaxies and the gas on their own do not have sufficient mass to allow the cluster to hold together. Therefore, they deduce that something called dark matter must be present in order to provide sufficient mass to produce the gravitational pull required.

  Galaxy

R.A.

Dec

Distance
(kpc)

1

Milky Way 17h45m -28°56m

7.7

2

Sagittarius Dwarf 18h55m -30°29m

22.9

3

LMC 05h23m -69°45m

48.3

4

SMC 00h52m -72°49m

60.3

5

Ursa Minor Dwarf 15h09m +67°12m

66.1

6

Sculptor Dwarf Spheroidal 01h00m -33°42m

84.3

7

Sextans Dwarf Spheroidal 10h13m -01°36m

85.9

8

Draco Dwarf 17h20m +57°54m

85.9

9

Carina Dwarf 06h41m -50°57m

97.7

10

Fornax Dwarf Spheroidal 02h39m -34°26m

134.9

The Milky Way is part of a galactic cluster known as the Local Group. The Milky Way and the Andromeda Nebula are the only two bright members of the Local Group. Other members include the Milky Way€™s two small companion galaxies, the Large and Small Magellanic Clouds. Most galaxies are members of clusters containing up to thousands of galaxies.

The 10 nearest members of the Local Group.  Click to load an interactive java applet containing the positions of all the galaxies in the local group. Use your mouse to rotate the applet and the up and down arrow keys to zoom in and out.



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