quasars Archives

November 4, 2024November 4, 2024 by Brian Koberlein

Another Way to Extract Energy From Black Holes?

Illustration of a powerful black hole and its magnetic field. Credit: L. Calçada/ESO

The gravitational field of a rotating black hole is powerful and strange. It is so powerful that it warps space and time back upon itself, and it is so strange that even simple concepts such as motion and rotation are turned on their heads. Understanding how these concepts play out is challenging, but they help astronomers understand how black holes generate such tremendous energy. Take, for example, the concept of frame dragging.

September 23, 2024September 23, 2024 by Brian Koberlein

Those Aren't Dyson Spheres, They're HotDOGs

Imagining the Universe as a collection of stellar bubbles. Credit: NASA

If there really are advanced alien civilizations out there, you’d think they’d be easy to find. A truly powerful alien race would stride like gods among the cosmos, creating star-sized or galaxy-sized feats of engineering. So rather than analyzing exoplanet spectra or listening for faint radio messages, why not look for the remnants of celestial builds, something too large and unusual to occur naturally?

September 3, 2024September 3, 2024 by Evan Gough

This Ancient Galaxy Merger Will Produce a very Luminous Quasar

This illustration depicts two quasars in the process of merging. There are many unanswered questions around galaxy mergers and the quasars that can result. Image Credit: NOIRLab/NSF/AURA/M. Garlick)

In the contemporary Universe, massive galaxies are plentiful. But the Universe wasn’t always like this. Astronomers think that galaxies grew large through mergers, so what we see in space is the result of billions of years of galaxies merging. When galaxies merge, the merger can feed large quantities of gas into their centers, sometimes creating a quasar.

Much of this is theoretical and shrouded in mystery, but astronomers might have found evidence of a galaxy merger creating a quasar.

July 5, 2024July 5, 2024 by Evan Gough

Black Holes Dominate Large Regions of Space, But They’re Mysterious

This image is from a black hole simulator. It shows a supermassive black hole, or quasar, surrounded by a swirling disk of material called an accretion disk. There are many unanswered questions about black holes and how they grow to be so massive. Simulations is one way of finding answers. Image Credit: Caltech/Phil Hopkins group

In the beginning, the Universe was all primordial gas. Somehow, some of it was swept up into supermassive black holes (SMBHs), the gargantuan singularities that reside at the heart of galaxies. The details of how that happened and how SMBHs accumulate mass are some of astrophysics’ biggest questions.

June 19, 2024June 19, 2024 by Andy Tomaswick

The Earliest Merging Quasars Ever Seen

Studying the history of science shows how often serendipity plays a role in some of the most important discoveries. Sometimes, the stories are apocryphal, like Newton getting hit on the head with an apple. But sometimes, there’s an element of truth to them. That was the case for a new discovery of the oldest pair of merging quasars ever discovered – and it all started with a pair of red blots on a picture.

May 2, 2024May 2, 2024 by Matt Williams

What Can AI Learn About the Universe?

Will AI become indispensable in an age of "big data" astronomy? Credit: DALL-E

Artificial intelligence and machine learning have become ubiquitous, with applications ranging from data analysis, cybersecurity, pharmaceutical development, music composition, and artistic renderings. In recent years, large language models (LLMs) have also emerged, adding human interaction and writing to the long list of applications. This includes ChatGPT, an LLM that has had a profound impact since it was introduced less than two years ago. This application has sparked considerable debate (and controversy) about AI’s potential uses and implications.

Astronomy has also benefitted immensely, where machine learning is used to sort through massive volumes of data to look for signs of planetary transits, correct for atmospheric interference, and find patterns in the noise. According to an international team of astrophysicists, this may just be the beginning of what AI could do for astronomy. In a recent study, the team fine-tuned a Generative Pre-trained Transformer (GPT) model using observations of astronomical objects. In the process, they successfully demonstrated that GPT models can effectively assist with scientific research.

March 18, 2024March 18, 2024 by Evan Gough

This New Map of 1.3 Million Quasars Is A Powerful Tool

This figure from the research shows the sky distribution of the new Quaia quasar catalogue in Galactic coordinates and is displayed using a Mollweide projection. The grey region across the center is the Milky Way, a blind spot in the Quaia catalogue. Image Credit: K. Storey-Fisher et al. 2024

Quasars are the brightest objects in the Universe. The most powerful ones are thousands of times more luminous than entire galaxies. They’re the visible part of a supermassive black hole (SMBH) at the center of a galaxy. The intense light comes from gas drawn toward the black hole, emitting light across several wavelengths as it heats up.

But quasars are more than just bright ancient objects. They have something important to show us about the dark matter.

March 16, 2024March 16, 2024 by Matt Williams

Little Red Dots in Webb Photos Turned Out to Be Quasars

A n EIGER JWST image of the luminous quasar J1148+5251, an extremely rare active SMBH of 10 billion solar masses (blue box). Two “baby quasars” (red boxes) are seen in the same dataset. © NASA, ESA, CSA, J. Matthee (ISTA), R. Mackenzie (ETH Zurich), D. Kashino (National Observatory of Japan), S. Lilly (ETH Zurich)

In its first year of operation, the James Webb Space Telescope (JWST) made some profound discoveries. These included providing the sharpest views of iconic cosmic structures (like the Pillars of Creation), transmission spectra from exoplanet atmospheres, and breathtaking views of Jupiter, its largest moons, Saturn’s rings, its largest moon Titan, and Enceladus’ plumes. But Webb also made an unexpected find during its first year of observation that may prove to be a breakthrough: a series of little red dots in a tiny region of the night sky.

These little red dots were observed as part of Webb’s Emission-line galaxies and Intergalactic Gas in the Epoch of Reionization (EIGER) and the First Reionization Epoch Spectroscopically Complete Observations (FRESCO) surveys. According to a new analysis by an international team of astrophysicists, these dots are galactic nuclei containing the precursors of Supermassive Black Holes (SMBHs) that existed during the early Universe. The existence of these black holes shortly after the Big Bang could change our understanding of how the first SMBHs in our Universe formed.

February 20, 2024February 21, 2024 by Matt Williams

The Brightest Object Ever Seen in the Universe

This artist’s impression shows the record-breaking quasar J059-4351, the bright core of a distant galaxy that is powered by a supermassive black hole. The light comes from gas and dust that's heated up before it's drawn into the black hole. Credit: ESO/M. Kornmesser

It’s an exciting time in astronomy today, where records are being broken and reset regularly. We are barely two months into 2024, and already new records have been set for the farthest black hole yet observed, the brightest supernova, and the highest-energy gamma rays from our Sun. Most recently, an international team of astronomers using the ESO’s Very Large Telescope in Chile reportedly saw the brightest object ever observed in the Universe: a quasar (J0529-4351) located about 12 billion light years away that has the fastest-growing supermassive black hole (SMBH) at its center.

December 22, 2023December 22, 2023 by Matt Williams

Watch 14 Years of Gamma-Ray Observations in This Fascinating NASA Video

Still from the video showing 14 years of data gathered by the Fermi Gamma-ray Space Telescope. Credit: NASA Goddard

The Fermi Gamma-ray Space Telescope, named in honor of noted physicist Enrico Fermi, has been in operation for almost a decade and a half, monitoring the cosmos for gamma rays. As the highest-energy form of light, these rays are produced by extremely energetic phenomena – like supernovae, neutron stars, quasars, and gamma-ray bursts (GRBs). In honor of this observatory’s long history, NASA’s Goddard Spaceflight Center has released a time-lapse movie that shows data acquired by the Fermi Space Telescope between August 2008 and August 2022.