Quasars Archives

December 20, 2022December 22, 2022 by Matt Williams

For the First Time, Astronomers Spot Stars in Galaxies that Existed Just 1 Billion Years After the Big Bang

Artist impression of a powerful young quasar. Credit: ESO/M. Kornmesser Credit: ESO/M. Kornmesser

Since it launched on December 25th, 2021 (quite the Christmas present!), the James Webb Space Telescope (JWST) has taken the sharpest and most detailed images of the Universe, surpassing even its predecessor, the venerable Hubble Space Telescope! But what is especially exciting are the kinds of observations we can look forward to, where the JWST will use its advanced capabilities to address some of the most pressing cosmological mysteries. For instance, there’s the problem presented by high-redshift supermassive black holes (SMBHs) or brightly-shining quasars that existed during the first billion years of the Universe.

To date, astronomers have not been able to determine how SMBHs could have formed so soon after the Big Bang. Part of the problem has been that, until recently, stars in host galaxies with redshift values of Z>2 (within 10.324 billion light-years) have been elusive. But thanks to the JWST, an international team of astronomers recently observed stars in quasars at Z>6 (within 12.716 billion light-years) for the first time. Their observations could finally allow astronomers to assess the processes in early quasars that governed the formation and evolution of the first SMBHs.

November 29, 2022November 29, 2022 by Andy Tomaswick

Quasars Produce Giant Jets That Focus Like Lasers. Why They Focus is Still a Mystery, but it’s not Coming From the Galaxy Itself

New technologies bring new astronomical insights, which is especially satisfying when they help answer debates that have been ongoing for decades. One of those debates is why exactly the plasma emitted from pulsars “collimates” or is brought together in a narrow beam. While it doesn’t provide a definitive answer to that question, a new paper from an international group of scientists points to a potential solution, but it will require even more advanced technologies.

October 20, 2022October 20, 2022 by Carolyn Collins Petersen

Webb Sees a Cluster of Galaxies Feeding a Quasar

an artistic concept of a quasar — Concept image of a galactic quasar. Astronomers used the Event Horizon Telescope to study details at the heart of one like this called NRAO 530. Credit: ParallelVision, Pixabay

There’s a galaxy protocluster out there in the distant universe that’s waving some tantalizing clues about cosmic history at astronomers. First of all, it’s got an active galactic nucleus—a quasar—at its heart. That’s a black hole emitting huge amounts of radiation. But now, they’ve found at least three young galaxies sending massive amounts of cosmic food (gas and dust) into the maw of that black hole-powered engine. Those infant galaxies are massive and moving fast around each other. And, just to make things interesting, dark matter is probably involved in the action.

September 25, 2022September 25, 2022 by Carolyn Collins Petersen

Gravity Really Tangled up the Light From a Distant Quasar

quasar lensed — The SDSS J1004+4112 gravitational lens creates five images of a distant quasar. Credit: European Space Agency, NASA, Keren Sharon (Tel-Aviv University) and Eran Ofek (CalTech))

Way back in 1979, astronomers spotted two nearly identical quasars that seemed close to each other in the sky. These so-called “Twin Quasars” are actually separate images of the same object. Even more intriguing: the light paths that created each image traveled through different parts of the cluster. One path took a little longer than the other. That meant a flicker in one image of the quasar occurred 14 months later in the other. The reason? The cluster’s mass distribution formed a lens that distorted the light and drastically affected the two paths.

July 8, 2022July 8, 2022 by Brian Koberlein

Supermassive Black Holes Formed Directly out of Enormous Streams of Cold gas

At the edge of known space are quasars. They are powerful cosmic engines capable of creating intense beams of light across billions of light years. And they are powered by supermassive black holes (SMBHs). Most galaxies have a SMBH, including our own galaxy, but for quasars to be so powerful their SMBHs must have become very large very quickly. We’re still learning just how they formed. We’ve long thought their formation involved a special set of circumstances, but a new study shows that early quasars could have formed purely from cold dark gas.

June 30, 2022July 11, 2022 by Carolyn Collins Petersen

Most Black Holes Spin Rapidly. This one… Doesn’t

This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientist suggests its accretion disk may be more elongated than shown in this image. Image Credit: EHT

A Chandra X-ray Observatory view of the supermassive black hole at the heart of quasar H1821+643. Courtesy NASA/CXC/Univ. of Cambridge/J. Sisk-Reynés et al.

Black holes. They used to be theoretical, up until the first one was found and confirmed back in the late 20th Century. Now, astronomers find them all over the place. We even have direct radio images of two black holes: one in M87 and Sagittarius A* in the center of our galaxy. So, what do we know about them? A lot. But, there’s more to find out. A team of astronomers using Chandra X-ray Observatory data has made a startling discovery about a central supermassive black hole in a quasar embedded in a distant galaxy cluster. What they found provides clues to the origin and evolution of supermassive black holes.

May 12, 2021May 10, 2021 by Paul M. Sutter

Astronomers see a Rare “Double Quasar” in a Pair of Merging Galaxies

Artist's conception of a double quasar. Image credit: ASA, ESA, Joseph Olmsted (STScI)

What’s better than a quasar? That’s right, two quasars. Astronomers have spotted for the first time two rare double-quasars, and the results show us the dynamic, messy consequences of galaxy formation.

April 12, 2021April 12, 2021 by Matt Williams

Gaia Finds 12 Examples of Einstein Crosses; Galaxies Being Gravitationally Lensed so we see Them Repeated 4 Times

Credit and : R. Hurt (IPAC/Caltech)/The GraL Collaboration

In 1915, Einstein put the finishing touches on his Theory of General Relativity (GR), a revolutionary new hypothesis that described gravity as a geometric property of space and time. This theory remains the accepted description of gravitation in modern physics and predicts that massive objects (like galaxies and galaxy clusters) bend the very fabric of spacetime.

As result, massive objects (like galaxies and galaxy clusters) can act as a lens that will deflect and magnify light coming from more distant objects. This effect is known as “gravitational lensing,” and can result in all kinds of visual phenomena – not the least of which is known as an “Einstein Cross.” Using data from the ESA’s Gaia Observatory, a team of researchers announced the discovery of 12 new Einstein Crosses.

February 9, 2021February 10, 2021 by Scott Alan Johnston

A New Technique to Find Cold Gas Streams That Might Make up the Missing (Normal) Matter in the Universe

Credit: Mark Myers, OzGrav/Swinburne University

Where is all the missing matter? That question has plagued astronomers for decades, because the Universe looks emptier than it should, given current theories about its makeup. Most of the Universe (70%) appears to be composed of Dark Energy, the mysterious force which is causing the Universe’s rate of expansion to increase. Another 25% of the Universe is Dark Matter, an unknown substance which cannot be seen, but has been theorized to explain the otherwise inexplicable gravitational forces which govern the formation of galaxies. That leaves Baryonic Matter – all the normal ‘stuff’ like you, me, the trees, the planets, and the stars – to make up just 5% of the Universe. But when astronomers look out into the sky, there doesn’t even seem to be enough normal matter to make up 5%. Some of the normal matter is missing!

February 2, 2021February 1, 2021 by Paul M. Sutter

Astronomers are Starting to Understand the Quasar Lifecycle

Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

Supermassive black holes have a complicated lifecycle. Sometimes they’re “on”, blasting out tremendous amounts of energy, and sometimes they’re “off’, where they sleep like dragons in their caves. By comparing the proportion of high-energy to low-energy waves emitted by quasars, astronomers are beginning to pin down how many black holes are sleeping, and when they’re likely to wake back up.