JKCS041 in 60 Seconds (Standard Definition)

[muffles12]

cool aliens galaxy

[patricknelson]

The bright hazy object in the middle is is actually a single vast elliptical galaxy, right?

[9tailedfoxe]

No, it's actually a galactic cluster, an area where a large number of galaxies are in close proximity. The narrator says that they are held together by gravitational pull, but that's just a convenient way of referring to it. It's now known that there is actually no such force as gravity. Mass warps time and space, creating the impression that some type of force is exerting directional pull. There's a little more to it than that also, but this is what the received wisdom currently says.