One of the most incredible images I ever seen, I think.What exactly it is? It’s of an object 5.4 billion light years away called MACSJ0717.5+3745, which is really just a catalog number and a coordinate on the sky, so it’s not nearly as awesome sounding as what it is: a massive collision between four separate galaxy clusters! COOL !
The image is a composite data of Hubble which sees visible light, Chandra which sees which sees high-energy X-rays.
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