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The UWA Zadko Telescope, owned by the University of Western Australia, was the first one in the world to capture the massive Universe event that saw a giant star collapsing into a black hole and emitting a massive gamma ray burst , fortunately for us in a very distant galaxy. The emission is believed to be about 11 billion years old, and is visible only now because of the time the light needed in order to travel from the site of the collapse to our planet. Australian astronomers say that, if such an explosion were to happen in a place...

The brightest gamma ray burst ever recorded arrived on December 27, 2004 at Universal Time 21 hours, 30 minutes. The blast was 100 times more intense than any burst that had been previously recorded, equaling the brightness of the full Moon, but at gamma ray wavelengths. Gamma ray counts spiked to a maximum in 1.5 seconds and then declined over a 5 minute period with 7.57 second pulsations. It was determined to have originated from SGR 1806-20, a neutron star 20 kilometers in diameter which rotates once every 7.5 seconds, matching the GRB pulsation period. SGR 1806-20 is located about...

Gravitational waves are caused by calamitous events in the Universe. Neutron stars that finally merge after circling each other for a long time can create them, and so can two black holes that collide with each other. But sometimes there's a burst of gravitational waves that doesn't have a clear cause. One such burst was detected by LIGO/VIRGO on January 14, and it came from the same region of sky that hosts the star Betelgeuse. Yeah, Betelgeuse, aka Alpha Orionis. The star that has been exhibiting some dimming behaviour recently, and is expected to go supernova at some point in...

Earth's gravitational wave observatories -- which hunt for ripples in the fabric of space-time -- just picked up something weird. The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors recorded an unknown or unanticipated "burst" of gravitational waves on Jan. 14. The gravitational waves we've detected so far usually relate to extreme cosmic events, like two black holes colliding or neutron stars finally merging after being caught in a death spiral. Burst gravitational waves have not been detected before and scientists hypothesize they may be linked to phenomena such as supernova or gamma ray bursts, producing a tiny "pop" when...

Betelgeuse has gotten dramatically dimmer over the last few weeks, astronomers say the change probably isn’t a symptom of an impending stellar explosion. That’s good news for any planets in the star’s orbit... But it’s disappointing news for Earth-based astronomers and stargazers, who haven’t been able to watch the death of a star with their unaided eyes since 1987, and may not have another chance for centuries. In 1987, a supernova called SN 1987A, marked the death of a blue giant star in the Large Magellanic Cloud, one of the dwarf galaxies that orbits the Milky Way. 168,000 years after...

A brief but extremely powerful cosmic blast from a distance galaxy has taken the record for the brightest light ever seen from Earth. It was emitted by a gamma ray burst seven billion light-years away and created more energy in a few seconds than the sun will burn in its 10 billion year lifetime. The discovery, led by researchers from Curtin University in Western Australia involved more than 300 scientists from around the world. Gamma-ray bursts are the most energetic events in the universe - the most massive since the Big Bang, says co author of the study, Dr Gemma...

The origin of the universe started with the Big Bang, but how the supernova explosion ignited has long been a mystery - until now. In a new paper appearing in Science Magazine, researchers detailed the mechanisms that could cause the explosion, which is key for the models that scientists use to understand the origin of the universe. "We defined the critical criteria where we can drive a flame to self-generate its own turbulence, spontaneously accelerate, and transition into detonation," says Kareem Ahmed, an assistant professor in UCF's Department of Mechanical and Aerospace Engineering and co-author of the study. ...

A recent study, published in the Astrophysical Journal, offers potential explanations for the appearance of a green blob near the galaxy's center, which appeared and disappeared within weeks. The main goal of the NuSTAR observations was to examine a supernova -- a huge star explosion. The green blob, known as an ultraluminous X-ray source (ULX...didn't appear during the first observation, but showed up during a second one 10 days later. Another space telescope, NASA's Chandra X-ray Observatory, then looked again and found the object, ULX-4, had quickly disappeared. "Ten days is a really short amount of time for such a...

In November of 2016, the sharp-eyed Gaia spacecraft spied a supernova that exploded some billion light-years from Earth. Astronomers followed up with more telescopes, and quickly realized that this supernova – dubbed SN2016iet – was an odd one in many ways. For one, the star that caused the supernova seemed to orbit far in the hinterlands of its tiny, previously unknown dwarf galaxy, some 54,000 light-years from its center. Most massive stars are born in denser clusters of stars, and it’s a puzzle how this one came to form so far out. And this star was extremely massive, starting life...

When dying red giant stars throw off material, dust particles form; those particles are later destroyed by supernova blast waves, which move through space at more than 6,000 miles per second, according to NASA. Supernova explosions are among the most powerful events in the universe and can produce a brightness equivalent to the light from billions of individual stars, NASA reports, adding that the blast wave from these explosions will destroy almost everything in its path.Observations from SOFIA — a Boeing747SP jetliner that's been modified to carry a 106-inch diameter telescope — tell a more mysterious story and show more...

A newly examined ice core shows what may be the chemical traces of supernovae that exploded a thousand years ago. Yuko Motizuki of the RIKEN research institute in Wako, Japan, and colleagues analysed the nitrate content of an ice core drilled at Dome Fuji station in Antarctica. Nitrate is produced in the atmosphere by nitrogen oxides, which in turn should be created by the gamma radiation from a supernova. Motizuki's group found high nitrate concentrations in three thin layers about 50 metres deep. Because snow gradually builds up into layers of ice, depth indicates age. After calibrating this icy calendar...

About 2.6 million years ago, an oddly bright light arrived in the prehistoric sky and lingered there for weeks or months. It was a supernova some 150 light years away from Earth. Within a few hundred years, long after the strange light in the sky had dwindled, a tsunami of cosmic energy from that same shattering star explosion could have reached our planet and pummeled the atmosphere, touching off climate change and triggering mass extinctions of large ocean animals, including a shark species that was the size of a school bus. The effects of such a supernova—and possibly more than...

A supernova is one of the most impressive natural phenomena in the Universe. Unfortunately, such events are often brief and transient, temporarily becoming as bright as an entire galaxy and then fading away. But given what these bright explosions – which occur when a star reaches the end of its life cycle – can teach us about the Universe, scientists are naturally very interested in studying them. Using data from the Dark Energy Survey Supernova (DES-SN) program, a team of astronomers recently detected 72 supernovae, the largest number of events discovered to date. These supernovae were not only very bright,...

The moment he saw the brilliant light captured by his camera, “it all clicked” for Victor Buso: All the times his parents woke him before sunrise to gaze at the stars, all the energy he had poured into constructing an observatory atop his home, all the hours he had spent trying to parse meaning from the dim glow of distant suns. “In many moments you search and ask yourself, why do I do this?” Buso said via email. This was why: Buso, a self-taught astronomer, had just witnessed the surge of light at the birth of a supernova — something...

The modern search for the Star of Bethlehem began with Johannes Kepler (imperial astronomer for Rudolph II of Germany), who shortly before Christmas in 1603 observed a conjunction (pairing) of Jupiter with Saturn from his observatory in Prague. That this occurred in the constellation of Pisces he thought was important as well – perhaps recalling Rabbi Isaac Abarvanel's belief, noted in his 15th-century commentary on Daniel, that not only does a conjunction of Jupiter and Saturn foretell important events, but in Pisces this holds a special significance for Israel; and such an event might even foretell the coming of the...

Researchers then scoured the globe for thin layers of radioactive isotopes in rock strata and in 1999 struck figurative gold: Samples from beneath the ocean revealed some hard metallic layers, known as ferromanganese crusts that form slowly over millions of years, containing iron-60, an isotope with a half-life of 2.6 million years -- so short that the material must be much younger than Earth. The iron-60 was in a stratum laid down 2.2 million years ago. Similar layers of iron-60 have since been found elsewhere in the oceans. Astronomers have also been scouring the skies for groups of stars that...

Sept. 28, 2005— A supernova blast 41,000 years ago started a deadly chain of events that led to the extinction of mammoths and other animals in North America, according to two scientists. If their supernova theory gains acceptance, it could explain why dozens of species on the continent became extinct 13,000 years ago. Mammoths and mastodons, both relatives of today's elephants, mysteriously died out then, as did giant ground sloths, a large-horned bison, a huge species of armadillo, saber-toothed cats, and many other animals and plants. Richard Firestone, a nuclear scientist at the U.S. Department of Energy's Lawrence Berkeley National...

Explosions In Space May Have Initiated Ancient Extinction On Earth Scientists at NASA and the University of Kansas say that a mass extinction on Earth hundreds of millions of years ago could have been triggered by a star explosion called a gamma-ray burst. The scientists do not have direct evidence that such a burst activated the ancient extinction. The strength of their work is their atmospheric modeling -- essentially a "what if" scenario. The scientists calculated that gamma-ray radiation from a relatively nearby star explosion, hitting the Earth for only ten seconds, could deplete up to half of the atmosphere's...

Supernova iPTF14hls was unremarkable when first detected by a partner telescope in San Diego on Sept. 22, 2014. The light spectrum was a textbook example of a Type II-P supernova, the most common type astronomers... The observatory was in the middle of a 7.5-year collaborative survey, so Arcavi focused on more-promising objects. But in February, 2015... a student working for Arcavi that winter, noticed the object had become brighter over the past five months. "He showed me the data," Arcavi said, "and he [asked], 'Is this normal?' and I said, 'Absolutely not. That is very strange. Supernovae don't do that,'"...

An angry monster lurks in the shoulder of the Hunter. We’re talking about the red giant star Betelgeuse, also known as Alpha Orionis in the constellation Orion. Recently, the Atacama Large Millimeter Array (ALMA) gave us an amazing view of Betelgeuse, one of the very few stars that is large enough to be resolved as anything more than a point of light. 650 light years distant, Betelgeuse is destined to live fast, and die young. The star is only eight million years old – young as stars go. Consider, for instance, our own Sun, which has been shining as a...