MSNBC - August 5, 2009
Stars in a distant galaxy move at stunning speeds — greater than 1 million mph, astronomers say.
These hyperactive stars move at about twice the speed of our sun through the Milky Way, because their host galaxy is very massive, yet strangely compact. The scene, which has theorists baffled, is 11 billion light-years away. It is the first time motions of individual stars have been measured in a galaxy so distant.
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Scientists used the new velocity measurements, conducted with the Gemini South telescope in Chile and the Hubble Space Telescope, to test the mass of a galaxy identified as 1255-0. The same way that the sun's gravity determines the orbiting speed of the Earth, the galaxy's gravity, and thus its mass, determines the velocities of the stars inside it.
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