Arizona scientists are getting a peek at the formation of the universe by observing quasars

Scientists are getting a closer look into the formation of our universe, thanks to a recent discovery.

The international team of researchers, including those from the University of Arizona, has observed 31 quasars from when the universe was 600 million to 800 million years old. For reference, that’s about 5% of its current age.

Quasars are among the brightest objects in the universe, and consist of black holes, among other things.

Xiaohui Fan is a professor of astronomy at the University of Arizona, and was involved in this discovery. The Show spoke with him about the significance of this new finding.

Full conversation

XIAOHUI FAN: So what we found was the most distant quasar that is known today in the universe, which translate to actually the most distant very massive black holes that we know in the universe.

MARK BRODIE: And what is the importance of that? Like why is that helpful to know?

XIAOHUI FAN: So, let me first explain what quasars are. These things are fascinating. They basically are extremely bright cores of galaxies that is powered by very massive black holes. So they can be as bright as, say, 1,000 or 10,000 times the Milky Way galaxy put together. And in the center of these quasars, there are black holes of probably a billion solar masses. So what we really find is that very early on in the history of the universe, maybe only 600, 700 million years after the Big Bang, when the universe is now about 14 billion years old. So in the first bit of time in the universe, those very, very massive black holes already existed, which was a surprise.

MARK BRODIE: So what does that tell us then maybe about the formation of the universe or about how things are going in the universe? Can it tell us anything?

XIAOHUI FAN: Right. So it tells us that very early in the universe, in a very early part of the history, like if you think of the universe as sort of a baby, an infant, a lot of things had already happened. So black holes, basically they take time to grow. They can grow in a million years or even 100 million years. They take hundreds of millions of years to grow to something like a billion solar masses. So that tells us that somehow the physics of the universe is such that black holes can grow very quickly and very early. And the theorists are still trying to understand why is that the case? What kind of condition can give rise to these very early and very massive black holes?

MARK BRODIE: Is that something different than what scientists had previously thought?

XIAOHUI FAN: Well, we don't know what we thought, of course. ... These are new discoveries that are just — so the race to find the most distant black holes have been going on for a very long time. And every time we push toward more distant black holes, we thought, "Oh, this is fairly early." Then we always find something even earlier and even earlier.

So I've been involved in this kind of research for the past 30 years, and at the time when I started — when we started doing this, the most distant black holes were quite a bit closer. And now they're pushing it to earlier and earlier in the universe.

So we don't quite know how early we can push it, but there are some simple calculation people can calculate, which basically says that our normal way of forming black holes doesn't quite work. ... And the normal way we mean is that if you have a very, very massive star — so say a star that is 100 times more massive than the sun, when they collapse, they collapse to a 100 times the sun black hole, a baby black hole, and then you begin to dump matter into it. And over time it's going to grow.

And we think that it would take something like a billion years or more to get this 1 billion solar mass black hole to form. And of course, the universe at the time that we observe these quasars were quite a bit younger. So we don't quite know why is the case, whether it's because you have some kind of physics that allow a black hole to form much bigger to begin with, or some other kind of physical processes that allow these things to grow much faster.

MARK BRODIE: Is it your expectation, though, that at some point somebody will find an older quasar, one from earlier on out there?

XIAOHUI FAN: Without giving too much, yes.

MARK BRODIE: Is that the hope, or would that be disappointing given your findings?

XIAOHUI FAN:... We are working on it. ... We are all working on finding the more distant one, and I think given the kind of data that we have access to, we will find more distant one very soon.

MARK BRODIE: How do you go about trying to find something so far away?

XIAOHUI FAN: So what make this happen is that what I mentioned, given new data, this is using a brand new space telescope called Euclid. It's a telescope that was launched by the European Space Agency about three years ago. It has a 600-million-pixel camera that looked at both the visible and infrared part of the sky ...

And that is much, much more efficient than what we used to do, which is use similar telescope from the ground. This is a space telescope so you don't have the light pollution, you don't have the atmosphere and all that. So that allow us to detect things much more efficiently and scan the sky much faster. That's what allowed us to discover this new quasar and the new most distant black hole.

Of course, this satellite only started to work three years ago. Still have four years of mission to go, at least. That's why I said I believe we will find a more distant one very soon, because we are just starting to look at data from this satellite.

MARK BRODIE: Are the black holes in the quasars that you've discovered similar or dissimilar to ones that you have found or others have found previously?

XIAOHUI FAN: So that's another sort of surprise is that they don't look any different from the black holes that we discovered in other quasars. Or more precisely, the quasars we discovered, their properties are very, very similar to the properties of quasars much more close by.

And that's different from other things, different from galaxies, different from stars. When you look at, like, James Webb Space Telescope, find a lot of very young galaxies that people probably have known, have heard, those young galaxies look quite different from our Milky Way galaxy. But when I look at the data of these very distant black holes compared to the data of very close-by quasars, if I don't know the distance, if I just look at the pictures, look at the light spectrum and put them on the same scale, they look rather similar. So that's another indication that these black holes and the surrounding of these black holes can form extremely quickly.

MARK BRODIE: Xiaohui Fan is a professor of astronomy at the University of Arizona.