At the Core


SagA*quietThere’s a supermassive black hole at the center of our Milky Way galaxy. It’s known as Sagittarius A* and shown in the center of this infrared (red and yellow) and X-ray (blue) composite image. Data from observations taken in orbit by Chandra‘s X-ray telescope was used to create an image the diffuse emission surrounding the black hole. See the close-up inset. The inset’s field of view covers an area about 1/2 light-year across the galactic center some 26,000 light-years away. These X-ray emissions originate in hot gas drawn from the winds of massive young stars near the galactic center. The Chandra data indicate that only 1% or so of the gas within the black hole’s gravitational influence ever reaches the event horizon after losing enough heat and angular momentum to fall into the black hole. The rest of the gas escapes in an outflow. This explains why the Milky Way’s black hole is so quiet, much fainter than might be expected in energetic X-rays.

Note: All data is subject to future verification. Beowulf Shaeffer was unavailable for comment.

Image Credit: NASA

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