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We live in a time when our telescopes can look back to almost the beginning of the universe. That includes the most distant reaches of the cosmos, and, of course, everything in between. Even though astronomers have a good idea of the different categories of objects in the universe, they’re still learning about the details. Take quasars, for example. They exist throughout the universe and appear to have been most active earlier in cosmic history. Understanding them has taken decades, and there is still a LOT to learn about these distant cosmic objects.

An artist's conception of the quasar Poiua'ena. Courtesy W.M. Keck Observatory. Quasars like this raise questions about the early universe. — An artist’s conception of the quasar Poniua’ena. Quasars like this raise questions about the early universe.Courtesy W.M. Keck Observatory.

The name “quasar” comes from the term “quasi-stellar object”. They caught astronomers’ attention back in the 1950s. That’s when the first ones were detected as strong radio-frequency emitters. Images taken later on showed dim, star-like objects that were the sources of the strong radio emissions. Yet, spectroscopic studies of the light emitted showed that these dim things lay at huge distances from Earth. What could be that strong in radio, show up as a dim star, and be so far away? It was a challenge for astronomers to explain them.

Today, we know quite a bit more about quasars. Their activity comes from the gobbling action of central supermassive black hole embedded in massive galaxies. Yes, black holes are the “engines” of quasars. Astronomers estimate that 50,000 exist and more will be discovered as they scan the sky.

Distance is Important

Recently, astronomers using the Gemini Telescope on Mauna Kea in Hawai’i found Poniua’ena, in a sky survey. Then, they followed up with spectroscopic studies using the Keck telescope. Poniua’ena is a Hawai’ian name. It means “unseen spinning source of creation, surrounded with brilliance.” (The catalog number is J1007+2115.) And, yes, it’s incredibly brilliant and, at just over 13 billion light-years, is nearly as far away as ULAS J1342+0928.

The most known distant quasar, called ULAS J1342+0928 is the current record-holder, at just over 13 billion light-years. The universe itself currently is somewhere around 13.7 billion years old. ULAS (for short) was born during a time when the first stars and galaxies were coalescing (the so-called “epoch of reionization” (EOR). So, that makes this quasar and Poniua’ena very old. They formed when the universe was very young. And, early quasars raise questions about their black holes. How could they grow so large so quickly to create quasars only a few hundred million years after the universe was born?

Quasars and the Epoch of Reionization

The EOR is, itself a fascinating challenge to study. Its distant, its objects are mostly dim, and astronomers are still watching for its earliest “ignition”. The birth of stars and galaxies started during the EOR, and about 400 million years into this period of cosmic history, the first black holes “seeds” may have begun to form. Interestingly, black holes are the central engines for quasars, but they are far more massive than the tiny ones that existed “way back when”.

Like other quasars, ULAS J1342+0928 and Poniua’ena get their power from the black holes at the hearts of their host galaxies. For ULAS, the black hole has about 800 million times the mass of the Sun. Poniua’ena’s is 1.5 billion solar masses.

Activities in the superheated region around the black holes (including jets) are what make the quasars look so bright. As material spins down into the black hole, it gets heated by friction, and also by the action of powerful magnetic fields. That heating produces radiation in the form of light across the electromagnetic spectrum. Some material escapes through powerful jets that stream from the region of the black hole. That, too, emits radiation. It’s a busy, hot, and lethal environment.

Looking for Quasars

So, are there other quasars just as distant as ULAS J1342+0928? and Poniua’ena? That’s the question astronomers want to answer as they survey the sky with various instruments that can detect the light and other radiation emanating from quasars. Since quasars appear early in cosmic time, they play some role in the history and evolution of the universe. The exact nature of that role remains to be understood. To even being to figure it out, astronomers have to do wide-area sky surveys to find these quasars, which is like searching for the proverbial needle in a haystack.

Forming Quasars

Obviously, to get to be a quasar, a massive galaxy needs a supermassive black hole at its heart. Early on in its formation, the galaxy may have a fairly small black hole in the core. But, to shine brightly across billions of light-years, the black hole has to become more massive. Since it grows by gathering more and mass into itself, eventually it becomes a supermassive black hole that powers the quasar. But, that raises an interesting conundrum.

Making a supermassive black hole takes a long time. And, for a quasar to exist when the first stars were forming after the birth of the universe, that means its supermassive black hole “engine” had to grow fairly fast. So, one big question about these early, distant quasars is: how did the universe produce such massive quasar engines so quickly?

Quasar Poniua’ena’s Early Existence

For Poniua’ena, that means its black hole had to start as a fairly massive black hole “seed” a hundred million years after the Big Bang occurred. That’s sort of like expecting a newborn baby to write the complete works of Shakespeare or formulate a new language only a few months after it is born. The existence of such massive black holes in the hearts of galaxies so soon after the universe was born challenges current theories about how they form.

The discovery and study of very distant quasars such as Poniua‘ena and ULAS J1342+0928 shed insight into the early universe. Both they and their massive galaxy hosts formed deep in the Epoch of Reionization. How and why did they form so early? What processes are at work to enable such massive objects to exist so early? Are there earlier quasars than these? The answers to all these questions will (if you’ll pardon the pun) shed light on the earliest events that we can possibly observe in our universe.

Have you ever heard someone say something dismissive about chemicals? Like comments that indicate these substances are somehow separate from us? It’s pretty common to see some people advocate for “natural” or “organic” products. Or, they preach against vaccinations because they wrongly assume these lifesaving injections are somehow “full of toxins and chemicals”.

It always sounds so silly, to me. I mean, the entire detectable universe consists of chemical elements. That means you and me and the planet and the Sun and Moon and… well, everything we can directly detect. So how can substances or objects consisting of chemicals be somehow unnatural?

Yes, I get that these people are often referring to specific things in vaccinations, for example. (Things that aren’t there, by the way. Or, they’re completely misunderstood or misinterpreted by people with a lack of critical thinking skills. But that’s a different topic.) That old argument about chemicals being somehow “unnatural” and “toxic” just ignores the reality of our existence.

Chemical Ingredients for Life Are as Old as the Universe

Take a look at your hand. Or the apple you’re eating. Or the coffee in your cup. And, the cup itself. Every object you can sense is made of chemicals. Or, to be more specific, chemical elements combined into molecules. Those are, themselves part of some kind of cellular matrix. I always liked the bit in the first “Cosmos” series where Dr. Carl Sagan suggested that, “If you wish to make an apple pie from scratch, you must first invent the universe.”

It’s true. The apple is a construct of atoms of elements that formed complex molecules. They combine to make the apple’s structure. So is the crust. So is the sugar (if you use that), and so are the other ingredients. And, so are all the things inside vaccines. In some cases,they have killed viruses that we wish to inoculate against. And, the viruses themselves are incredibly complex mixtures of molecules made of chemical elements.

Space is where we come from, it’s where the chemicals of life originate and spread seed to places where life can thrive. NASA/Jenna Mottar.

So, where do those “fixin’s” come from? Why from the stars, of course. Other than hydrogen and a little lithium, most other chemical elements come from stars. So, calcium (for your bones), iron (for your blood), potassium (to regulate heart activity), and other elements, come from stars. They cook them up as they age and evolve, and when they die, stars scatter that “stuff” to the universe. There, it gets taken up (eventually), into clouds of gas and dust, which are the birthplaces of stars and planets. And, planets (as we suspect from our sample of one) are formation places for life.

Chemical Clouds Hold Clues to Life

We know that interstellar clouds contain hydrogen. That element was created in the Big Bang. The clouds also harbor complex organic molecules. Many of those substances are actually the building blocks of life. And, they seem to be in many such cloud complexes.

Astronomers, astrobiologists (the folks who study life elsewhere), and astrochemists (who study chemical elements in the universe) want to know how soon in the universe these molecules appeared. What causes their formation? In a disk of gas and dust, when do the building blocks of life appear? One suggestion is that they form in response to rising heat and pressures in a protoplanetary disk. That’s the part of the cloud where a star and its planets are born.

When Do Chemical Percursors Form?

At least one study shows that those complex organic molecules can exist long before a protostar begins to form. In that research, scientists found molecules of methanol and acetaldehyde in a large number of starforming regions called “pre-stellar” or “starless”. These places don’t have stars, yet. However, they seem to be places where cold dust and gases coalesce. There, they form the seeds that eventually will give rise to stars (and planets). And, according to the scientists who are studying these regions, they contain life’s building blocks, before worlds exist to take advantage of them.

These two molecules aren’t the only prebiotic precursors found in such clouds. A simple sugar molecule called glycolaldehyde has been detected, along with a host of other carbon-based molecules. These discoveries show us that we are in a chemical universe that provides the seeds of life.

Finding Chemical Precursors

To study the clouds for their particular discovery, a team of scientists at the University of Arizona’s Steward Observatory, used a 12-meter dish telescope to study emissions from interstellar clouds. They peered at 31 starless cores scattered throughout a star-forming region known as the Taurus molecular cloud. That cloud lies about 440 light-years from Earth. Each core is quite large, about the width of a thousand solar systems. None of the cores has a star at its heart, and probably won’t for several hundred thousand years.

That’s according to Yancy Shirley, who worked with graduate student Samantha Scibelli on the project. “This tells us that the basic organic chemistry needed for life is present in the raw gas prior to the formation of stars and planets,” he said. The processes that bring chemical elements together to form organic molecular building blocks of life aren’t well understood. “The exact processes at play are still being debated because the theoretical models still don’t quite match what we see,” Scibelli said. With the current research, she and the team can constrain the formation sequence that might be taking place in the clouds.

Their work will tell theorists how abundant these molecules are. Eventually, it may be possible to figure out exactly how these molecules form and why they exist where they do. That would open up a wider range of places to study the chemicals that create life. (You can read more about this specific research here.

Accepting a Chemical Universe

It’s thanks to the prebiotic molecules that formed in our local neighborhood that we even exist today. Studies like the one at Arizona are the first steps toward trying to figure out where life exists elsewhere. Even more intriguing: it plays a big role in revealing where life could form next. And, we have chemical elements to thank for it. We’re all made of star-stuff, which is, in turn, made of chemicals. So, now I wonder, what could be more natural than chemicals? After all, they’re what we are.

The Spacewriter's Ramblings

distant Quasars: Action in the Early Universe