A Blazar in the Early Universe: Details Revealed in Galaxy's Jet 12.8 Billion Light-Years from Earth

Credit: Spingola et al.; Bill Saxton, NRAO/AUI/NSF.

The supersharp radio "vision" of the National Science Foundation's Very Long Baseline Array (VLBA) has revealed previously unseen details in a jet of material ejected at three-quarters the speed of light from the core of a galaxy some 12.8 billion light-years from Earth. The galaxy, dubbed PSO J0309+27, is a blazar, with its jet pointed toward Earth, and is the brightest radio-emitting blazar yet seen at such a distance. It also is the second-brightest X-ray emitting blazar at such a distance. 

In this image, the brightest radio emission comes from the galaxy's core, at bottom right. The jet is propelled by the gravitational energy of a supermassive black hole at the core, and moves outward, toward the upper left. The jet seen here extends some 1,600 light-years, and shows structure within it.

At this distance, PSO J0309+27 is seen as it was when the universe was less than a billion years old, or just over 7 percent of its current age.

An international team of astronomers led by Cristiana Spingola of the University of Bologna in Italy, observed the galaxy in April and May of 2020. Their analysis of the object's properties provides support for some theoretical models for why blazars are rare in the early universe. The researchers reported their results in the journal Astronomy & Astrophysics.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Contacts and sources: 
Dave Finley
The National Radio Astronomy Observatory i

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Baffling radio signal coming from inside Milky Way Galaxy

Astronomers detect mysterious bursts of radio signals from distant galaxy; Photo: cbsnews

A mysterious intense blast of radio energy has been detected inside our own galaxy, astronomers have said in a new study published in the journal Nature.

The Independent reported that the detected signals are Fast Radio Bursts (FRBs) that last only a small fraction of a second, however, it can possess more than the sun itself. Despite the intensity of FRBs, their causal origin remains largely unknown.

In the new study, however, astronomers observed a fast radio burst in our own Milky Way Galaxy for the first time – which is closer than any FRBs that was previously detected and might help astronomers understand their origin.

Scientists have long struggled to uncover the origin of these intense blasts because they are so short, unpredictable and originate far away. But the consensus is they are formed within some of the most extreme conditions possible in our universe — with potential explanations ranging from dying stars to alien technology. 

The bursts of radio energy appear to have come from a magnetar, or a star with a very powerful magnetic field, the scientists who discovered the new FRBs said. 

“This great mystery as to what would produce these great outbursts of energy, which until now we’ve seen coming from halfway across the universe,” said Kiyoshi Masui, assistant professor of physics at MIT, who led the team’s analysis of the FRB’s brightness, adding: “This is the first time we’ve been able to tie one of these exotic fast radio bursts to a single astrophysical object.”

The detection began on 27 April when researchers using two space telescopes – multiple X-ray and gamma-ray emissions – coming from a magnetar at the other end of our galaxy. The next day, researchers used two North American telescopes to observe that patch of sky and picked up the blast that came to be known as FRB 200428.

Pragya Chawla, one of the co-authors on the study and a senior Ph.D. student in the Physics Department at McGill, said they calculated such an intense burst coming from another galaxy which would be indistinguishable from some fast radio bursts. “This really gives weight to the theory suggesting that magnetars could be behind at least some FRBs,” he added.FRBs were first discovered in 2007, immediately gave speculation on what could be able to cause such intense blasts of energy. The new study is the first to provide evidence linking the FRBs with magnetars. At the very least, that could be a valuable clue to the origin of at least some of those FRBs. Source: https://www.daily-bangladesh.com/
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