5 Dec 2024

Summary

Legendary Active Galaxy Contains a Monster Black Hole

Amateur astronomers can hunt for a unique starlike object, called 3C 273, which holds the record as the farthest target available to be viewed from Earth through a common-sized backyard telescope. Because 3C 273 pours out the light equivalent of trillions of suns it can be seen across over two billion light-years! Today we know it is the blinding bright core of an active galaxy powered by a supermassive black hole gobbling up material.

Back in 1963, 3C 273 was a complete mystery. Astronomer Maarten Schmidt zoomed in on the object because its loud radio emission caught his attention. It looked like a star in the world's most powerful telescope of the time. But its light was weird. The expansion of the universe stretched the light into red wavelengths. This yardstick, called cosmological redshift, corresponds to a distance of 2.5 billion light-years for 3C 273. That's too far away for a lone star to be seen. It became an utterly new mysterious class of object called a quasar, or quasi-stellar object. Its extreme brightness and gusher of energy was staggering for something to exist among far-flung galaxies.

In 1929, long before the quasar's discovery, astrophysicist Sir James Jeans suggested that the bright pinpoint centers of galaxies are where matter is pouring into the universe from another dimension. This conjecture was later dubbed a "white hole." But exactly the opposite is true. Today we know quasars and the broader class of active galactic nuclei containing monster black holes that goggle up matter. Quasars are now a fundamental part of astrophysics and cosmology. These brilliant beacons are intimately tied to the formation and evolution of stars and galaxies.

The new Hubble image is opening a gateway into better understanding quasars. Hubble's vision is so sharp it photographed weird things within 16,000 light-years of the black hole such as filaments, lobes, and a mysterious L-shaped structure. Some of the objects may be captured small satellite galaxies falling into the nearly 900-million-solar-mass black hole. At least 1 million quasars are evenly scatted across the entire sky. And, 3C 273 started it all as the first quasar ever discovered..

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Full Article

Astronomers have used the unique capabilities of NASA's Hubble Space Telescope to peer closer than ever into the throat of an energetic monster black hole powering a quasar. A quasar is a galactic center that glows brightly as the black hole consumes material in its immediate surroundings.

The new Hubble views of the environment around the quasar show a lot of "weird things," according to Bin Ren of the Côte d'Azur Observatory and Université Côte d'Azur in Nice, France. "We've got a few blobs of different sizes, and a mysterious L-shaped filamentary structure. This is all within 16,000 light-years of the black hole."

Some of the objects could be small satellite galaxies around the black hole, and so they could offer the materials that will accrete onto the central super massive black hole, powering the bright lighthouse. "Thanks to Hubble's observing power, we're opening a new gateway into understanding quasars," said Ren. "My colleagues are excited because they've never seen this much detail before."

Quasars look starlike as point sources of light in the sky (hence the name quasi-stellar object). The quasar in the new study, 3C 273, was identified in 1963 by astronomer Maarten Schmidt as the first quasar. At a distance of 2.5 billion light-years it was too far away for a star. It must have been more energetic than ever imagined, with a luminosity over 10 times brighter than the brightest giant elliptical galaxies. This opened the door to an unexpected new puzzle in cosmology: What is powering this massive energy production? The likely culprit was material accreting onto a black hole.

In 1994 Hubble's new sharp view revealed that the environment surrounding quasars is far more complex than first suspected. The images suggested galactic collisions and mergers between quasars and companion galaxies, where debris cascades down onto supermassive black holes. This reignites the giant black holes that drive quasars.

For Hubble, staring into the quasar 3C 273 is like looking directly into a blinding car headlight and trying to see an ant crawling on the rim around it. The quasar pours out thousands of times the entire energy of stars in a galaxy. One of closest quasars to Earth, 3C 273 is 2.5 billion light-years away. (If it was very nearby, a few tens of light-years from Earth, it would appear as bright as the Sun in the sky!) Hubble's STIS instrument can serve as a coronagraph to block light from central sources, not unlike how the Moon block the Sun's glare during a total solar eclipse. Astronomers have used STIS to unveil dusty disks around stars to understand the formation of planetary systems, and now they can use STIS to better understand quasars’ host galaxies. The Hubble coronograph allowed astronomers to look eight times closer to the black hole than ever before.

Scientists got rare insight into the quasar's 300,000-light-year-long extragalactic jet of material blazing across space at nearly the speed of light. By comparing the STIS coronagraphic data with archival STIS images with a 22-year separation, the team led by Ren concluded that the jet is moving faster when it is farther away from the monster black hole.

"With the fine spatial structures and jet motion, Hubble bridged a gap between the small-scale radio interferometry and large-scale optical imaging observations, and thus we can take an observational step towards a more complete understanding of quasar host morphology. Our previous view was very limited, but Hubble is allowing us to understand the complicated quasar morphology and galactic interactions in detail.  In the future, looking further at 3C 273 in infrared light with the James Webb Space Telescope might give us more clues," said Ren.

At least 1 million quasars are scattered across the sky. They are useful background "spotlights" for a variety of astronomical observations. Quasars were most abundant about 3 billion years after the big bang, when galaxy collisions were more common.