The Milky Way has two satellitegalaxies, the Large and Small Magellanic
Clouds. The orbits of these galaxies tells us that the mass in the halo
around the Milky Way is 5 to 10 times greater than the mass we can
see.
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.
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