ASTRONOMERS claim to have discovered what might be the hungriest - most luminous object in the visible universe - a supermassive black hole swallowing a star a day.

That would be the massive equivalent of 370 Suns a year disappearing down a a cosmic gullet 11 billion years ago, at the dawn of TIME.

Burp indeed.

In a paper published in Nature Astronomy, Christian Wolf of the Australian National University and his colleagues from Australia and Europe, called the object at the center of a newly discovered quasar  known as J0529-4351 ''the fastest growing black hole in the universe.''

According to their estimates, this was one of the most massive black holes ever found : 17 billion times as massive as the sun.

But other astrophysicists cast doubt on the result, questioning the methods by which the mass and luminosity of the new quasar has been estimated. They said the calculations were too uncertain to be conclusive.

'' They may have the right value, but I don't think other observers would be shocked if it turned out to be the true mass was somewhat less,'' said Daniel Holz, a theoretical astrophysicist at the University of  Chicago.

'' It does seem like an extreme object,'' he said.But, he added, '' I would be shocked if this turned out to be the most luminous quasar on the sky.''

Jenny Greene, a professor of astrophysical sciences at Princeton University, called the result ''cute.''

'' It's nice to pick out the brightest of something,'' she said.

Given the historical variability of quasars, she said, '' It's not clear this object is even really is more luminous than the others.''

Chung-Pei Ma, an astrophysicist at the University of California, Berkeley, weighed in saying that estimates of black hole masses could be off by a factor of two or three, '' too large to make me lose sleep over the viability of prevailing cosmological models.''

This is a story of mind-bending big numbers, no matter how it comes out : 

'' There's the weird game we play in astronomy where we're always looking for the biggest, the brightest, the youngest, the oldest, etc,'' Dr.Holz said in an email.

'' Record breaking objects are an efficient way to learn about the universe. Extremes help illuminate the contours of a problem, and to help push our theories up to [ or past ] their breaking points.''

So it is with quasars and black holes. Quasars are distant objects that look like stars in the sky. In the 1960s, they were discovered to be emitting improbable torrents of energy, outshining all the stars in the galaxy in which they were embedded.

Astronomers have since concluded that all the energy is produced by matter falling into giant black holes. Just as a bathtub can't drain in an instant, matter can disappear down the cosmic drain only at a rate, called the Eddington limit, that depends on the black hole size.

The rest is trapped in a sort of turnstile of doom, a swirling sparkling like disc radiating energy. Which makes black holes, despite their name, the brightest objects in the universe.

BECAUSE they look like stars, quasars are hard to find in the sky. Dr. Wolf, a dedicated quasar hunter, said in an email that he relished the hunt. '' It makes me feel like a kid again,'' he wrote.

In this case, the quasar was hiding in plain sight in the database of the European Space Agency's Gaia spacecraft, which has mapped the locations and properties of billions of stars since it was launched in 2013.

This Master Essay Publishing continues. The World Students Society thanks author Dennis Overbye.


Post a Comment

Grace A Comment!