Radio Jets from Distant Quasars

Using data from the Very Large Array Sky Survey (VLASS), astronomers have detected young radio-emitting jets from supermassive black holes in distant active galaxies.

VLASS is a project that will survey the sky visible from NSF’s Karl G. Jansky Very Large Array (VLA) — about 80% of the entire sky — three times over seven years. The observations began in 2017 and the first of the three scans now is complete.

Dr. Kristina Nyland, a postdoctoral researcher at the Naval Research Laboratory, and colleagues compared data from this scan with data from the FIRST survey that used the VLA to observe a smaller portion of the sky between 1993 and 2011.

“We found galaxies that showed no evidence of jets before but now show clear indications of having young, compact jets,” Dr. Nyland said.

“Jets like these can strongly affect the growth and evolution of their galaxies, but we still don’t understand all of the details.”

“Catching newborn jets with surveys like VLASS provides a measure of the role of powerful radio jets in shaping the lives of the galaxies over billions of years.”

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Image credit: Sophia Dagnello, NRAO / AUI / NSF.

An artist’s conception of a galaxy with an active nucleus propelling jets of material outward from the galaxy’s center.

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Image credit: Nyland et al. / Sophia Dagnello, NRAO / AUI / NSF.

VLA images of three galaxies in the study, comparing what was seen in the earlier FIRST survey and the later VLASS; the newly-appearing bright radio emission indicates that the galaxies launched new jets of material sometime between the dates of the two observations.

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Tour: The Recipe for Powerful Quasar Jets

Some supermassive black holes launch powerful beams of material, or jets, away from them, while others do not. Astronomers may now have identified why.

Using data from NASA's Chandra X-ray Observatory and several other telescopes, researchers have studied more than 700 quasars — rapidly growing supermassive black holes — to isolate the factors that determine why these black holes launch jets.

Jets from supermassive black holes can inject huge amounts of energy into their surroundings and strongly influence the evolution of their environments. Previously, scientists realized that a supermassive black hole needs to be spinning rapidly to drive strong jets — but not all rapidly spinning black holes have jets.