supernova Archives

October 26, 2022October 26, 2022 by Evan Gough

How Dangerous are Nearby Supernovae to Life on Earth?

A composite image of SN 1987A from Hubble, Chandra, and ALMA. Image Credit: By ALMA (ESO/NAOJ/NRAO)/A. Angelich. Visible light image: the NASA/ESA Hubble Space Telescope. X-Ray image: The NASA Chandra X-Ray Observatory - http://www.eso.org/public/images/eso1401a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=30512379

Life and supernovae don’t mix.

From a distance, supernovae explosions are fascinating. A star more massive than our Sun runs out of hydrogen and becomes unstable. Eventually, it explodes and releases so much energy it can outshine its host galaxy for months.

But space is vast and largely empty, and supernovae are relatively rare. And most planets don’t support life, so most supernovae probably explode without affecting living things.

But a new study shows how one type of supernova has a more extended reach than thought. And it could have consequences for planets like ours.

September 16, 2022September 16, 2022 by Laurence Tognetti

Can Astronomers Predict Which Stars Are About to Explode as Supernovae?

In a recent study submitted to High Energy Astrophysical Phenomena, a team of researchers from Japan discuss strategies to observe, and possibly predict precursor signatures for an explosion from Local Type II and Galactic supernovae (SNe). This study has the potential to help us better understand both how and when supernovae could occur throughout the universe, with supernovae being the plural form of supernova (SN). But just how important is it to detect supernovae before they actually happen?

June 24, 2022June 24, 2022 by Evan Gough

Recent Supernovae Produced Giant Cavities in the Orion Nebula

This image of the Orion Nebula shows the puzzilng Barnard's Loop feature, a structure made of gas first identified in 1898, Image Credit: Michael Foley

The Orion Nebula is a well-known feature in the night sky and is visible in small backyard telescopes. Orion is a busy place. The region is known for active star formation and other phenomena. It’s one of the most scrutinized features in the sky, and astronomers have observed all kinds of activity there: planets forming in protoplanetary disks, stars beginning their lives of fusion inside collapsing molecular clouds, and the photoevaporative power of massive hot stars as they carve out openings in clouds of interstellar gas.

But supernova explosions are leaving their mark on the Orion Nebula too. New research says supernovae explosions in recent astronomical history are responsible for a mysterious feature first formally identified in the night sky at the end of the 19th century. It’s called Barnard’s Loop, and it’s a gigantic loop of hot gas as large as 300 light-years across.

June 23, 2022June 23, 2022 by Andy Tomaswick

Do Ancient Coins Record the Supernova of 1054?

SN 1054 was one of the most spectacular astronomical events of all time. The supernova explosion eventually formed what is today known as the M1 – the Crab Nebula. But in 1054 AD, the year it occurred, it was an ultrabright star in the sky and one of only eight recorded supernovae in the history of the Milky Way. However, it was only noted by half of the literate world. Primarily written about in the East, especially in China, SN 1054 was almost wholly absent from the Western record. Except, potentially, for a subtle hint at it in the most unlikely of places – some Byzantine coins.

June 3, 2022May 31, 2022 by Paul M. Sutter

Hubble Sees a Surviving Companion Star After its Partner Went Supernova

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

When stars die they’re often not alone, and for the first time astronomers have found a companion to a supernova, lingering long after its sibling destroyed itself.

May 9, 2022May 6, 2022 by Paul M. Sutter

We can Probably Find Supernovae Enhanced by Gravitational Lensing, We Just Need to Look

Using the microlensing metthod, a team of astrophysicists have found the first extra-galactic planets! Credit: NASA/Tim Pyle

Gravitational lensing provides an opportunity to see supernovae and other transients much farther than we normally can. A new research proposal outlines a plan to use a comprehensive catalog of strong gravitational lenses to capture these rare events at extreme distances.

April 11, 2022April 11, 2022 by Evan Gough

Supernova Remnant Cassiopeia A is Lopsided

Coloured image of Cassiopeia A based on data from the space telescopes Hubble, Spitzer and Chandra. Image Credit: NASA/JPL-Caltech [via Wikimedia]

Cassiopeia A is the remnant of a supernova that exploded 11,000 light-years away. The light from the exploding star likely reached Earth around 1670 (only a couple of years before Newton invented the reflecting telescope.) But there are no records of it because the optical light didn’t reach Earth.

The Cass A nebula ripples with energy and light from the ancient explosion and is one of the most-studied objects in deep space. It’s an expanding gas shell blasted into space when its progenitor star exploded.

But Cass A isn’t expanding evenly, and astronomers think they know why.

January 19, 2022January 19, 2022 by Brian Koberlein

A new Kind of Supernova has Been Discovered

Hen 2-427, a Wolf–Rayet star. Credit: ESA/Hubble & NASA, Judy Schmidt

We often think of supernova explosions as inevitable for large stars. Big star runs out of fuel, gravity collapses its core and BOOM! But astronomers have long thought at least one type of large star didn’t end with a supernova. Known as Wolf-Rayet stars, they were thought to end with a quiet collapse of their core into a black hole. But a new discovery finds they might become supernovae after all.

January 12, 2022January 12, 2022 by Evan Gough

Astronomers Watch a Star Die and Then Explode 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

It’s another first for astronomy.

For the first time, a team of astronomers have imaged in real-time as a red supergiant star reached the end of its life. They watched as the star convulsed in its death throes before finally exploding as a supernova.

And their observations contradict previous thinking into how red supergiants behave before they blow up.

January 11, 2022January 11, 2022 by Evan Gough

Nearby Supernovae Were Essential to Life on Earth

Distant past supernovae could be linked by cosmic ray particles to climate change on Earth and changes in biodiversity. Courtesy: Henrik Svensmark, DTU Space.

It’s almost impossible to comprehend a supernova explosion’s violent, destructive power. An exploding supernova can outshine its host galaxy for a few weeks or even months. That seems almost impossible when considering that a galaxy can contain hundreds of billions of stars. Any planet too close to a supernova would be completely sterilized by all the energy released, its atmosphere would be stripped away, and it may even be shredded into pieces.

But like many things in nature, it all comes down to dose.

A certain amount of supernova activity might be necessary for life to exist.