supernova Archives

July 30, 2020July 30, 2020 by Paul M. Sutter

There’s a flash of ultraviolet just as a white dwarf is exploding as a supernova

Artist's impression of a supernova. Supernovae bombarded Earth with radiation that has implications for the development of life on Earth. Image Credit: NASA

Astronomers recently spotted a rare type of supernova explosion that was accompanied by a massive flare of ultraviolet radiation. Untangling the mystery of the UV flash could help unravel the mysterious nature of these supernova explosions, and even help us understand the age of the universe.

July 20, 2020July 20, 2020 by Evan Gough

A Star had a Partial Supernova and Kicked Itself Into a High-Speed Journey Across the Milky Way

The material ejected by the supernova will initially expand very rapidly, but then gradually slow down, forming an intricate giant bubble of hot glowing gas. Eventually, the charred remains of the white dwarf that exploded will overtake these gaseous layers, and speed out onto its journey across the Galaxy. Credit: University of Warwick/Mark Garlick

Supernovae are some of the most powerful events in the Universe. They’re extremely energetic, luminous explosions that can light up the sky. Astrophysicists have a pretty good idea how they work, and they’ve organized supernovae into two broad categories: they’re the end state for massive stars that explode near the end of their lives, or they’re white dwarfs that draw gas from a companion which triggers runaway fusion.

Now there might be a third type.

July 17, 2020July 16, 2020 by Paul M. Sutter

Supernovae shockwaves aren’t spherical

Artist’s impression of gamma-ray burst with orbiting binary star. Credit: University of Warwick/Mark Garlick

When stars blow up, they tend to release their energy in a roughly spherical shape. But much after the initial blast, the resulting shock waves can sometimes be elongated in one direction. A team of theorists used laboratory lasers to identify the potential culprit: magnetic fields.

April 22, 2020April 22, 2020 by Evan Gough

Super-Supernova Released Ten Times More Energy than a Regular Supernova

Artist's conception of SN2016aps, a candidate pulsational pair instability supernova. The explosion energy of SN2016aps, fueled by the shedding of a massive shell of gas, was ten times that of a normal-sized supernova, making SN2016aps the most massive supernova ever identified. Credit: M. Weiss

It’s easy to run out of superlatives and adjectives when your puny human language is trying to describe humongously-energetic events in the Universe. So now it’s down to this: a really powerful supernova is a “super-supernova.”

But whatever name we give it, it’s a monster. A monsternova.

March 10, 2020March 10, 2020 by Nancy Atkinson

It Looks Like Betelgeuse was Dimming Because it was Dusty After All

Betelgeuse before and after dimming — This comparison image shows the star Betelgeuse before and after its unprecedented dimming. The observations, taken with the SPHERE instrument on ESO’s Very Large Telescope in January and December 2019, show how much the star has faded and how its apparent shape has changed.

It’s been said that dust built the Universe. And it turns out dust may be the culprit for building up what are likely false hopes of soon witnessing a massive supernova for the star Betelgeuse.

March 4, 2020March 4, 2020 by Evan Gough

Two White Dwarfs Merged Together Into a Single “Ultramassive” White Dwarf

An artist’s impression of two white dwarfs in the process of merging. Depending on the combined mass, the system may explode in a thermonuclear supernova, or coalesce into a single heavy white dwarf, as with WDJ0551+4135. This image is free for use if used in direct connection with this story but image copyright and credit must be University of Warwick/Mark Garlick

Astronomers have found a white dwarf that was once two white dwarfs. The pair of stars merged into one about 1.3 billion years ago. The resulting star, named WDJ0551+4135, is about 150 light years away.

February 18, 2020February 19, 2020 by Matt Williams

There Could be Meteors Traveling at a Fraction of the Speed of Light When They Hit the Atmosphere

Multi-photo composite showing Perseid meteors shooting from their radiant point in the constellation Perseus. Earth crosses the orbit of comet 109P/Swift-Tuttle every year in mid-August. Debris left behind by the comet burns up as meteors when it strikes our upper atmosphere at 130,000 mph. Credit: NASA

It’s no secret that planet Earth is occasionally greeted by rocks from space that either explode in our atmosphere or impact on the surface. In addition, our planet regularly experiences meteor showers whenever its orbit causes it to pass through clouds of debris in the Solar System. However, it has also been determined that Earth is regularly bombarded by objects that are small enough to go unnoticed – about 1 mm or so in size.

According to a new study by Harvard astronomers Amir Siraj and Prof. Abraham Loeb, it is possible that Earth’s atmosphere is bombarded by larger meteors – 1 mm to 10 cm (0.04 to 4 inches) – that are extremely fast. These meteors, they argue, could be the result of nearby supernovae that cause particles to be accelerated to sub-relativistic or even relativistic speeds – several thousand times the speed of sound to a fraction of the speed of light.

January 8, 2020January 8, 2020 by Evan Gough

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

An artist's image of a white dwarf drawing material away from its companion. Image Credit: NASA

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.

December 11, 2019December 15, 2019 by Matt Williams

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

Some of the most dramatic events in the Universe occur when certain stars die — and explode catastrophically in the process. Such explosions, known as supernovae, mainly occur in a couple of ways: either a massive star depletes its fuel at the end of its life, become dynamically unstable and unable to support its bulk, collapses inwards, and then violently explodes; or a white dwarf in an orbiting stellar couple syphons more mass off its companion than it is able to support, igniting runaway nuclear fusion in its core and beginning the supernova process. Both types result in an intensely bright object in the sky that can rival the light of a whole galaxy. In the last 20 years the galaxy NGC 5468, visible in this image, has hosted a number of observed supernovae of both the aforementioned types: SN 1999cp, SN 2002cr, SN2002ed, SN2005P, and SN2018dfg. Despite being just over 130 million light-years away, the orientation of the galaxy with respect to us makes it easier to spot these new ‘stars’ as they appear; we see NGC 5468 face on, meaning we can see the galaxy’s loose, open spiral pattern in beautiful detail in images such as this one from the NASA/ESA Hubble Space Telescope.

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.

October 23, 2019October 23, 2019 by David Dickinson

Did an Ancient Supernova Force Humans to Walk Upright?

Crab nebula — The Crab Nebula (Messier 1) a recent supernova remnant noticed as a bright new star in Taurus in the 11th century. Image credit and copyright: Nick Howes.

A new study hints at a possible fascinating twist in human evolution. Did a chain of cosmic events triggered by a nearby ancient supernova force humans to walk upright?