Galaxy Story

The Galaxy in Which We Live

Page 6 of 6

Dynamics of Local Group Galaxies

Our Milky Way Galaxy belongs to a cluster of galaxies named the Local Group. There are other members of the Local Group like the Large Magellanic Cloud, the Small Magellanic Cloud, or the Andromeda galaxy (M31). Finding out about the orbits of these nearby galaxies will give us hints on how the Universe looked soon after the Big Bang.

Fundamental Physics

Einstein's General Theory of Relativity states that light is deflected when passing close to a massive body.

When observing stars from the Earth or from a satellite , we can measure the displacement of the stellar image due to the Sun. It is important to measure this and other relativistic numbers and see if they fit predictions of General Relativity, in view of recent suggestions that Einstein's theory might break down at such levels.

More detailed information can be found on the Gaia web site.

Click on the thumbnail below to explore how the path of light is affected by the size and mass of a stellar body as the light passes nearby:

The Effect of Gravity on Light


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