Astronomers have discovered the second farthest quasar ever found, 13 billion light-years from Earth. It has a supermassive black hole at its heart that tilts the cosmic scale to 1.5 billion times the mass of the Sun, making it the most massive black hole seen at that distance.* *.
And that, it turns out, is a problem.
The technical name of the quasar is J1007 + 2115 (after its coordinates in the sky), but astronomers have nicknamed it Pōniuā’ena, an indigenous Hawaiian word meaning “invisible rotating source of creation, surrounded by brilliance,” which is a so precise and poetic at the same time. a description of an active galaxy that I’ve heard†.
It was found in a study of the sky looking for very distant galaxies like this, and then astronomers observed it more carefully with several very large telescopes to obtain a spectrum from it, confirming its distance.
A quasar is an active galaxy, where the supermassive black hole at its core is actively eating matter around it. As matter builds up in a disk around the hole before it falls, friction heats it up to ridiculously high temperatures, causing it to glow brightly. This disk is so luminous that it can easily overshadow all the stars in the galaxy, and these disks are the most powerful continuous sources of energy in the Universe.
A spectrum, dividing light into hundreds or thousands of individual colors, can tell you a lot about an object. For example, when the material rotates around the black hole, we see the color of red and blue light (the material on one side moves away from us and on the other side towards us). The amount of this change tells us the mass of the black hole, which is 1.5 billion times the mass of the Sun, a huge number. Only one other quasar is known that far from us, J1342 + 0908, and its black hole is only half of this massive one.
Also, as the Universe expands, distant objects seem to move away from us, imparting a redshift of light that can tell us how far away it is. In this case, the wavelengths have been redshifted by a factor of 8.5 (due to the mathematics of this, we say it has a redshift of 7.5; here is a redshift of 0, in the local Universe, a redshift of 1 is where the wavelengths have doubled, etc.), which means it is far away. It is not quite up to J1342 + 0908, but its black hole is much larger.
And that is the problem. The universe is only 13.8 billion years old, which means this black hole grew enormously Quick. I like it, Really quickly, much faster than current theories think is possible.
This has been a recurring problem with distant galaxies. One solution to this is that they can grow faster than we think. That is possible, although difficult. If too much gas flows into them, the large amount of energy generated by the heat tends to expel the gas, choking the flow. There are ways to get around this, a bit, using things like magnetic fields and the like, but it’s still hard to get enough matter to fall.
Another idea is that they started relatively large. Supermassive black holes start from smaller seed black holes, some with only (!) Ten or a hundred thousand times the mass of the Sun. If the seed starts bigger, that helps. Or maybe a bunch of them can form separately and come together to merge, although that’s hard enough to do, too.
For the Pōniuā’ena black hole to reach 1.5 billion swollen solar masses in just 800 million years after the Big Bang, it would have to have started as a seed with 10,000 solar masses 100 million years after the Big Bang (or one of 300,000 solar masses 275 million years after the Bang). That still implies a lot Growth It is not clear how this can happen in detail, although many ideas have been published.
And that is the beauty of this observation. Not a record per seBut it’s another piece of data that astronomers can use to figure out what’s going on at the edge of the observable Universe.
We don’t really have a clear idea of what’s going on (well, what it happened) at this time in the young Universe (go here and look for the word “reionization”), and every galaxy we find is another light that shines, literally, on the possible answers.
* *Last week I wrote about a much more massive black hole, but it was located 12,500 million light years from Earth. It is 500 million light years further still, which is significant at these distances; the young Universe changed rapidly, and it is important to find them in an even slightly more remote location.
†The name was given as part of a program called A Hua He Inoa, which unites traditional Hawaiian language and astronomy, which is a great idea.
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