A quasar is kind of like a giant vacuum cleaner in space, slurping up everything in its path. In more scientific terms, a quasar is a bright object powered by a monstrous black hole at its center. Recently, astronomers have stumbled upon something even more incredible: baby quasars.
A groundbreaking observation recently captured by the James Webb Space Telescope (JWST) has led astrophysicists to rethink the nature of black holes. Assistant Professor Jorryt Matthee at the Institute of Science and Technology Austria believes that “faint little red dots” in recent JWST images are “small versions of extremely massive black holes”—or baby quasars.
Above: A galaxy spins in space. Image courtesy of Getty Images.
While it’s difficult to see a black hole, researchers visualize quasars when their galactic core is illuminated by gas and dust falling into them. Quasars are some of the most luminous celestial objects, outshining our entire galaxy on the order of thousands.
How Did the Team Discover Baby Quasars?
Matthee’s team was studying data from two powerful JWST programs—EIGER and FRESCO—to find hints about the early cosmos. These programs capture massive amounts of data on distant objects, such as their unique light characteristics known as “spectra.” Combing through the data, they noticed small red specks peppering the sky. These objects were invisible to older telescopes like the Hubble Space Telescope, which lacked superior infrared capabilities.
Above: A JWST image of the quasar J1148+5251, a rare supermassive black hole. Image courtesy of NASA, ESA, CSA, J. Matthee (ISTA), R. Mackenzie (ETH Zurich), D. Kashino (National Observatory of Japan), and S. Lilly (ETH Zurich).
By examining this light code from a tiny patch of sky, Matthee’s team found light signals from hydrogen atoms called H-alpha lines, which hinted at something big: quasars. But these quasars were particularly small—like speedy snackers—compared to the monstrous black holes powering regular quasars. As a result, the EIGER program wasn’t designed to find the little red dots. Instead, the team “found them by chance in the same dataset,” Matthee said.
While normal quasars are blue, super bright, and millions of times heavier than our sun, these baby quasars are red and weigh only tens to hundreds of millions of times as much as the sun. “They appear red because they are dusty,” Matthee explained. Eventually, these baby black holes will clear out the dust inside them and become the giants we see today. These “baby quasars” are destined to balloon into supermassive black holes—ones that are hard to image, ultra-heavy, and appear blue thanks to the bright disc of matter that feeds them.
What Makes Baby Quasars a Big Deal?
These tiny snackers challenge everything we thought we knew about how supermassive black holes grow. By studying black holes in their nascent years, scientists hope to unlock the secrets of how these cosmic giants evolve. It would offer insights into the lifecycle of quasars and black holes: how they grow, how they appear to a telescope, and what stages precede their change into the giants we observe today. According to Matthee, “These special objects could change the way we think about the genesis of black holes.”
Baby quasars could also help us answer questions about the time it takes for this lifecycle to occur. Some black holes grow very quickly, becoming so massive that they power bright bursts of light. These “problematic quasars” were a mystery because they seemed to grow too quickly for our current theories.
Ultimately, this research goes beyond black holes. Studying baby quasars could help us understand how galaxies form, how the universe is structured, and even the basic laws of physics. The JWST might have found us a missing puzzle piece to see the bigger picture of the universe.
Written by Rudransh Singh Palta, this article was selected as a winner of our 2024 High School Science Communication Challenge. From Jaipur, Rajasthan in northern India, Palta is a sophomore at Jayshree Periwal International School. He hopes to study computational physics in the future. Outside of school, he enjoys playing badminton, reading self-help books, and writing.