Interesting article
http://www.esa.int/esaSC/SEMWD1AATME_index_0.html
Thanks to data from ESA’s XMM-Newton X-ray satellite, a team of international scientists found a comet-like ball of gas over a thousand million times the mass of the sun hurling through a distant galaxy cluster over 750 kilometres per second.
This colossal 'ball of fire' is by far the largest object of this kind ever identified.
The gas ball is about three million light years across, or about five thousand million times the size of our solar system. It appears from our perspective as a circular X-ray glow with a comet-like tail nearly half the size of the moon.
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