Two Black Holes

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Two Black Holes
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What's happening at the center of active galaxy 3C 75? The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. Surrounded by multimillion degree x-ray emitting gas, and blasting out jets of relativistic particles the supermassive black holes are separated by 25,000 light-years.

Round Ball Gives More Evidence of Mars' Watery Past

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Round Ball Gives More Evidence of Mars' Watery Past
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Via Ian O'Neill

According to MSL scientists based at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., the ball isn't as big as it looks — it's approximately one centimeter wide. Their explanation is that it is most likely something known as a "concretion." Other examples of concretions have been found on the Martian surface before — take, for example, the tiny haematite concretions, or "blueberries", observed by Mars rover Opportunity in 2004 — and they were created during sedimentary rock formation when Mars was abundant in liquid water many millions of years ago.