We’ve found the brightest ever supernova but can’t explain it

[Reefa]

 

The brightest supernova ever seen has been confirmed, but it still has astronomers puzzling over what unknown type of star could have been responsible.

 

Supernovas mark the violent deaths of stars that collapse on themselves and blow up. They are some of the brightest and most energetic objects in the universe.

 

This one, called ASASSN-15lh, is about 3.8 billion light years away, 200 times more powerful than most supernovas, and twice as bright as the previous record holder.

 

It shines 20 times brighter than the combined output of the Milky Way’s 100 billion stars, and in the last six months, it has spewed as much energy as the sun would in 10 lifetimes, says Krzysztof Stanek of the Ohio State University, co-principal investigator of the All Sky Automated Survey for SuperNovae (ASAS-SN) network that spotted the explosion.

 

“This is really on steroids, and then some,” he says. “If it was in our own galaxy, it would shine brighter than the full moon; there would be no night, and it would be easily seen during the day.”

 

He spotted the outburst on 14 June while perusing telescope images over his morning coffee, and alerted the rest of the ASAS-SN team, including Subo Dong at the Kavli Institute for Astronomy and Astrophysics at Peking University. Dong quickly signalled a network of amateur astronomers who help the team confirm possible supernovae, and received some images that night.

 

The team suspected it was a rare “superluminous” supernova, but the 14-centimetre ASAS-SN telescopes were too small to see the details required to be sure. Bad weather and problems with instruments delayed further investigation by 10 days. Finally the Southern African Large Telescope revealed details about the star’s chemical makeup when it exploded, allowing Dong to calculate its distance and confirm that the object was the brightest supernova ever recorded. It was 2 am in Beijing when Dong received these results, “but I was too excited to sleep the rest of the night”, he says.

 

 

The supernova appears to be in an old, large galaxy that is bigger and brighter than the Milky Way, which is unusual because the handful of other known superluminous supernovas have been found in dim, small and young galaxies. It’s also much hotter than other stellar explosions.

 

Mammoth or magnetar

 

Those oddities mean astronomers are not totally sure what it is, Stanek says.

 

“My analogy is that we have been studying elephants, and our project has found the biggest elephant ever,” he says. “There’s a chance it is not an elephant, but a mammoth, a relic from the earlier universe.”

 

It might be a different exotic object called a magnetar, a special kind of neutron star with an intense magnetic field. But ASASSN-15lh is more powerful than magnetars can possibly become, so that seems unlikely, says Steve Rodney at the University of South Carolina.

 

It could also be the remains of a star being pulled apart by a supermassive black hole, or an ordinary supernova that is being magnified by a cosmic lens, an effect of gravity. But both of those theories are unlikely: the explosion lacks the hydrogen and helium that would be the hallmarks of a black hole’s lunch, and the explosion’s relatively close distance makes lensing implausible.

 

ASASSN-15lh has just moved behind the sun, but astronomers have been taking new data until this week with the space-based Swift Gamma Ray Burst Explorer. The team was awarded time on the Hubble Space Telescope and hope to use it in a couple months – after the object fades a little bit, so the telescope can see its host galaxy in better detail. The Hubble observations will give astronomers more insight into the strange object’s origins. Stanek says he’s eager to hear new theories about what it could be.

 

“When you see something which has never been seen before, you get excited,” he says. “It doesn’t happen that often.”

 

Journal: Science, 10.1126/science.aac9613

https://www.newscientist.com/article/dn28772-weve-found-the-brightest-ever-supernova-but-cant-explain-it/

 

[BiC]

Quote

“When you see something which has never been seen before, you get excited,” he says. “It doesn’t happen that often.”

he get some pu**y finally? lol

[Batu69]

Astronomers find brightest star explosion ever, located 3.8bn light-years away, which is more luminous than entire Milky Way

 

An artist’’s impression of the superluminous supernova ASASSN-15lh (Assassin) as it would appear from an exoplanet located in the host galaxy of the supernova.

 

Astronomers have discovered the brightest star explosion ever, a super supernova that easily outshines our entire Milky Way.

An international team revealed “the most powerful supernova observed in human history” Thursday in the latest Science journal. The astronomers used a network of telescopes around the world to spot the record-breaking supernova last year.

 

Super luminous supernovas — extra bright stellar explosions — are believed to be rare. The newly discovered supernova is especially rare: It is more than twice as luminous as any supernova observed to date, including the previous record-holders.

 

At its peak intensity, it is believed to be 20 times more luminous than the entire Milky Way. Some estimates put it at 50 times brighter.

 

It is 570 billion times brighter at its peak than our sun.

Lead author Subo Dong of China’s Peking University said when he learned the magnitude of the discovery last summer, he was “too excited to sleep the rest of the night.” Fellow researcher Benjamin Shappee of the Carnegie Institution for Science in Pasadena, California, didn’t believe the results at first, which seemed “surreal.”

 

“Discoveries like this are the reason I am an astronomer,” Shappee said in an email. “Nature is extremely clever and it is often more imaginative than we can be.”

Labeled ASASSN-15lh for the All-Sky Automated Survey for SuperNovae and pronounced “assassin,” the mega blast is located in a galaxy perhaps 3.8 billion light-years away. The precise galaxy is unknown. There are other puzzles as well.

 

“The explosion’s mechanism and power source remain shrouded in mystery because all known theories meet serious challenges in explaining the immense amount of energy ASASSN-15lh has radiated,” Dong said in a statement.

 

The next step for scientists is to figure out its incredible power source. Other super supernovas, like this one, could be out there. More observatories are on the case, including some NASA spacecraft. The Hubble Space Telescope will be pressed into service this year as well.

 

Dong said ASASSN-15lh “may lead to new thinking and new observations of the whole class of super luminous supernova.”

 

Article source

[SURbit]

Nature is SO amazing and technology that leads to these kinds of discoveries are

an important part of our lives now.

 

Not knowing -why I ask- I understand our Sun gives us (earth) light, heat, ultra violet rays,

that wrecks havoc sometimes with present day technology.

Is there a danger from this or any other "Super luminous supernovas - extra bright stellar explosions", 

of course in some future time (as many miles are having to be covered) from these to us here on earth?

 

With these extra bright stellar explosions - are we then able to detect other astrological

heavenly bodies not seen from otherwise darken space? 

 

I sure hope so, discoveries of an even more filled and amazing, awing  universe 

[Reefa]

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