Hubble spots double quasars in merging galaxies - EarthSky

Each pair is thought to reside in the midst of two merging galaxies in the very distant universe.

Because quasars vary in brightness depending on how much material the black hole is consuming at the time, they produce a slight flickering appearance.

That’s very close on a cosmic distance scale; by comparison, our sun is about 26,000 light-years from the supermassive black hole at the center of our Milky Way galaxy.

A quasar’s energy is thought to be created when a supermassive black hole furiously feeds on infalling matter.

If we could see them today, as they are right now, we might find that each quasar pair has merged to form a new giant black hole.

Scientists hope the discoveries will yield a new way to probe collisions among galaxies and the merging of supermassive black holes in the early universe.

This truly is the first sample of dual quasars at the peak epoch of galaxy formation with which we can use to probe ideas about how supermassive black holes come together to eventually form a binary.

Finding dual quasars at this early epoch is important because we can now test our long-standing ideas of how black holes and their host galaxies evolve together.

Both quasars have supermassive black holes at their cores.

A new study suggests that, as the 2 galaxies merge and the quasars get closer together, the 2 black holes will merge to form an even-more-massive black hole.

Several billion years from now, as our two galaxies begin to interact and pull in material from each other, the currently quiet supermassive black holes at the centers of the galaxies will fire up.

Bottom line: Scientists have recently released Hubble images of the farthest- and oldest-known pairs of quasars in merging galaxies.