The Brightest Supernova Ever Seen was Caused by a White Dwarf Spiraling into a Red Giant

Super-luminous supernovae are the brightest explosions in the Universe. In just a few months, a super-luminous supernova can release as much energy as our Sun will in its entire lifespan. And at its peak, it can be as bright as an entire galaxy.

One of the most-studied super-luminous supernovae (SLSN) is called SN 2006gy. Its origin is uncertain, but now Swedish and Japanese researchers say they might have figured out what caused it: a cataclysmic interaction between a white dwarf and its massive partner.

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Forget Betelgeuse, the Star V Sagittae Should Go Nova Within this Century

The star V Sagittae is the next candidate to explode in stellar pyrotechnics, and a team of astronomers set the year for that cataclysmic explosion at 2083, or thereabouts. V Sagittae is in the constellation Sagitta (latin for arrow,) a dim and barely discernible constellation in the northern sky. V Sagittae is about 1100 light years from Earth.

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This Galaxy Has Been Home to 5 Supernovae in the Last 20 Years

When stars die, they don’t die quietly but prefer to go out with a bang! This is known as a supernova, which occurs when a star has expended all of its fuel and undergoes gravitational collapse. In the process, the outer layers of the star will be blown off in a massive explosion visible from billions of light-years away. For decades, NASA has been monitoring galaxies beyond the Milky Way and detected numerous supernova taking place.

For instance, over the past 20 years, the Hubble Space Telescope has been monitoring the galaxy NGC 5468 – an intermediate spiral galaxy located roughly 130 million light-years from Earth in the constellation Virgo. In that time, this galaxy has experienced 5 supernovae and, thanks to its orientation (perpendicular to our own), astronomers have been able to study this galaxy and its supernovae in glorious detail.

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Astronomers Finally Find the Neutron Star Leftover from Supernova 1987A

Astronomers at Cardiff University have done something nobody else has been able to do. A team, led by Dr. Phil Cigan from Cardiff University’s School of Physics and Astronomy, has found the neutron star remnant from the famous supernova SN 1987A. Their evidence ends a 30 year search for the object.

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Pulsar Seen Speeding Away From the Supernova That Created it

When a star exhausts its nuclear fuel towards the end of its lifespan, it undergoes gravitational collapse and sheds its outer layers. This results in a magnificent explosion known as a supernova, which can lead to the creation of a black hole, a pulsar or a white dwarf. And despite decades of observation and research, there is still much scientists don’t know about this phenomena.

Luckily, ongoing observations and improved instruments are leading to all kinds of discoveries that offer chances for new insights. For instance, a team of astronomers with the National Radio Astronomy Observatory (NRAO) and NASA recently observed a “cannonball” pulsar speeding away from the supernova that is believed to have created it. This find is already providing insights into how pulsars can pick up speed from a supernova.

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Astronomers are Continuing to Watch the Shockwaves Expand from Supernova SN1987A, as they Crash Into the Surrounding Interstellar Medium

When stars reach the end of their life cycle, many will blow off their outer layers in an explosive process known as a supernova. While astronomers have learned much about this phenomena, thanks to sophisticated instruments that are able to study them in multiple wavelengths, there is still a great deal that we don’t know about supernovae and their remnants.

For example, there are still unresolved questions about the mechanisms that power the resulting shock waves from a supernova. However, an international team of researchers recently used data obtained by the Chandra X-Ray Observatory of a nearby supernova (SN1987A) and new simulations to measure the temperature of the atoms in the resulting shock wave.

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Astronomers See the Exact Moment a Supernova Turned into a Black Hole (or Neutron Star)

A look at The Cow (approximately 80 days after explosion) from the W.M. Keck Observatory in Maunakea, Hawaii. The Cow is nestled in the CGCG 137-068 galaxy, 200 million light years from Earth. Image Credit:Raffaella Margutti/Northwestern University

On June 17th 2018, the ATLAS (Asteroid Terrestrial-impact Last Alert System) survey’s twin telescopes spotted something extraordinarily bright in the sky. The source was 200 million light years away in the constellation Hercules. The object was given the name AT2018cow or “The Cow.” The Cow flared up quickly, and then just as quickly it was gone.

What was it?

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A Guide to Hunting Zombie Stars

R Aquarii is called a symbiotic star system because of their relationship. As the white dwarf draws in material from the Red Giant, it ejects some if it in weird looping patterns, seen in this Hubble image. Image Credit: By Judy Schmidt from USA - Symbiotic System R Aquarii, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=63473035

Apparently not all supernovas work. And when they fail, they leave behind a half-chewed remnant, still burning from leftover heat but otherwise lifeless: a zombie star. Astronomers aren’t sure how many of these should-be-dead creatures lurk in the interstellar depths, but with recent simulations scientists are making a list of their telltale signatures so that future surveys can potentially track them down.

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A Supernova 2.6 Million Years Ago Could Have Wiped Out the Ocean’s Large Animals

Artist's impression of a Type II supernova. Credit: ESO

For many years, scientists have been studying how supernovae could affect life on Earth. Supernovae are extremely powerful events, and depending on how close they are to Earth, they could have consequences ranging from the cataclysmic to the inconsequential. But now, the scientists behind a new paper say they have specific evidence linking one or more supernova to an extinction event 2.6 million years ago.

About 2.6 million years ago, one or more supernovae exploded about 50 parsecs, or about 160 light years, away from Earth. At that same time, there was also an extinction event on Earth, called the Pliocene marine megafauna extinction. Up to a third of the large marine species on Earth were wiped out at the time, most of them living in shallow coastal waters.

“This time, it’s different. We have evidence of nearby events at a specific time.” – Dr. Adrian Melott, University of Kansas.

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