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M31 Lightcurve Data

Lightcurve of M31

Galex image of M31

Recap: Your astronomy professor has tasked the class with determining the velocity of Andromeda with respect to the Milky Way. You thought of three possible ways to do this, one of which will give you the right answer. You've decided to try using the 1/r2 relationship to find the distance to M31 at two different times and then calculate the velocity from the difference in the two distances.

Here is a graph of the light curve of M31, as observed with a ground telescope at the local university.

M31 light curve

Light curve of M31

percent over the timescale observed.


A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

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