The above images shows Sagittarius A*, the supermassive black hole at the center of our galaxy. NASA's Chandra X-ray Observatory and the European Southern Observatory's Very Large Telescope and Chile have both detected X-ray flares coming from Sgr A* (as it is called) and scientists didn't know why. But a new theory has emerged: Asteroids that come within about 100 million miles of the black hole (perhaps as the result of a close encounter with a planet or a star) are torn to pieces by the hole's tidal forces (middle-right panel). The fragments are then vaporized by Sgr A*'s gases, resulting in the observed flares (bottom-right panel), much like what happens to a meteor that burns up in Earth's atmosphere. In the image above, the three panels at right are an artist's representation of this process.

Below, recent Pictures of the Day:

Image: NASA.

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