Imagine the Universe!

Hubble's Constant and Distance to M31

You now know that you need two pieces of information in order to use Hubble's Law to solve for M31's velocity: the distance to M31 and Hubble's constant.

Looking up "distance to M31" on the web, it is easy to find that the Andromeda galaxy (the other name for M31) is 2,900,000 light years away. Wow! That seems like a long way, but actually the Andromeda galaxy is one of our nearby neighbors! The value of Hubble's constant, H0 is trickier. It is currently generally accepted that Hubble's constant falls betwen 75 and 85 km/sec/Mpc. Finding the exact value is an area of active research in astronomy today!

Info Click here for more information on Hubble's constant, and its accepted value. (http://csep1.phy.ornl.gov/guidry/violence/hubble_constant.html)

: km/sec, assuming a value for Hubble's constant of 80 km/sec/Mpc.

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Nicholas White (Director), within the Laboratory for High Energy Astrophysics at NASA's Goddard Space Flight Center.

The Imagine Team
Project Leader: Dr. Jim Lochner
All material on this site has been created and updated between 1997-2004.

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