Supernovae Archives

November 21, 2024November 21, 2024 by Evan Gough

The First Close-Up Picture of Star Outside the Milky Way

WOH G64 is a massive red supergiant star in the Large Magellanic Cloud. Thanks to the ESO's Very Large Telescope Interferometer, this is the first close-up picture of a star in another galaxy. Image Credit: ESO/K. Ohnaka et al.

Like a performer preparing for their big finale, a distant star is shedding its outer layers and preparing to explode as a supernova.

Astronomers have been observing the huge star, named WOH G64, since its discovery in the 1970s. It’s one of the largest known stars, and also one of the most luminous and massive red supergiants (RSGs). The star is surrounded by an envelope of expelled star-stuff, which could indicate it’s getting ready to explode.

November 5, 2024November 5, 2024 by Evan Gough

Habitable Worlds are Found in Safe Places

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle) — This is Kepler 186f, an exoplanet in the habitable zone around a red dwarf. We've found many planets in their stars' habitable zones where they could potentially have surface water. But it's a fairly crude understanding of true habitability. Image Credit: NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

When we think of exoplanets that may be able to support life, we hone in on the habitable zone. A habitable zone is a region around a star where planets receive enough stellar energy to have liquid surface water. It’s a somewhat crude but helpful first step when examining thousands of exoplanets.

However, there’s a lot more to habitability than that.

November 1, 2024November 1, 2024 by Mark Thompson

The Connection Between Black Holes and Dark Energy is Getting Stronger

JWST NIRCam imaging of star-forming protocluster PHz G191.24+62.04, 11 billion years ago as the universe was approaching the peak of star formation. These early galaxies are among the most active star-forming galaxies observed between 10.5 and 11.5 billion years ago. Each galaxy seen in this image is therefore producing many black holes, which are converting matter into dark energy according to the cosmologically coupled black hole hypothesis. This image shows the two "modules" of JWST NIRCam: The leftmost module contains the protocluster, and the rightmost module is an adjacent blank field. Each module sees thousands of galaxies.

The discovery of the accelerated expansion of the Universe has often been attributed to the force known as dark energy. An intriguing new theory was put forward last year to explain this mysterious force; black holes could be the cause of dark energy! The theory goes on to suggest as more black holes form in the Universe, the stronger the pressure from dark energy. A survey from the Dark Energy Spectroscopic Instrument (DESI) seems to support the theory. The data from the first year of operation shows the density of dark energy increases over time and seems to correlate with the number and mass of black holes!

July 16, 2024July 16, 2024 by Andy Tomaswick

Only Hubble Could Make this Measurement of a Supernova

Calculating the distance to far-away objects, such as galaxy clusters and quasars, is difficult. But it is also critical to our understanding of how the universe evolves. Luckily, humanity has a trusty workhorse that has been collecting data for such calculations for decades—Hubble. It is by far the best telescope suited to the job, as described by a recent NASA press release about a distance measurement to a supernova in a nearby galaxy.

June 29, 2024June 30, 2024 by Laurence Tognetti

Supernovae: Why study them? What can they teach us about finding life beyond Earth?

Artist’s illustration of a bright and powerful supernova explosion. (Credit: NASA/CXC/M.Weiss)

Universe Today has recently investigated a myriad of scientific disciplines, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, organic chemistry, black holes, cryovolcanism, planetary protection, and dark matter, and what they can teach us about how we got here, where we’re going, and whether we might find life elsewhere in the universe.

Here, Universe Today discusses the explosive field of supernovae—plural for supernova—with Dr. Joseph Lyman, who is an assistant professor in the Astronomy and Astrophysics Group at the University of Warwick, regarding the importance of studying supernovae, the benefits and challenges, the most intriguing aspects about supernovae he’s studied throughout his career, what supernovae can teach us about finding life beyond Earth, and any advice he can offer upcoming students who wish to pursue studying supernovae. Therefore, what is the importance of studying supernovae?

June 14, 2024June 14, 2024 by Scott Alan Johnston

Webb is an Amazing Supernova Hunter

80 objects (circled in green) that changed in brightness over time, as seen by JWST. Most of these are supernovae. NASA, ESA, CSA, STScI, JADES Collaboration

The James Webb Space Telescope (JWST) has just increased the number of known distant supernovae by tenfold. This rapid expansion of astronomers’ catalog of supernovae is extremely valuable, not least because it improves the reliability of measurements for the expansion of the universe.

April 12, 2024April 12, 2024 by Evan Gough

The Brightest Gamma Ray Burst Ever Seen Came from a Collapsing Star

This artist's visualization of GRB 221009A shows the narrow relativistic jets (emerging from a central black hole) that gave rise to the gamma-ray burst (GRB) and the expanding remains of the original star ejected via the supernova explosion. Credit: Aaron M. Geller / Northwestern / CIERA / IT Research Computing and Data Services

After a journey lasting about two billion years, photons from an extremely energetic gamma-ray burst (GRB) struck the sensors on the Neil Gehrels Swift Observatory and the Fermi Gamma-Ray Space Telescope on October 9th, 2022. The GRB lasted seven minutes but was visible for much longer. Even amateur astronomers spotted the powerful burst in visible frequencies.

It was so powerful that it affected Earth’s atmosphere, a remarkable feat for something more than two billion light-years away. It’s the brightest GRB ever observed, and since then, astrophysicists have searched for its source.

April 3, 2024April 3, 2024 by Evan Gough

The Large Magellanic Cloud isn’t Very Metal

This image shows the Large and Small Magellanic Clouds in the sky over the ESO's Paranal Observatory and the four telescopes of the VLT. Image Credit: By ESO/J. Colosimo - http://www.eso.org/public/images/potw1511a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=38973313

The Large Magellanic Cloud (LMC) is the Milky Way’s most massive satellite galaxy. Because it’s so easily observed, astronomers have studied it intently. They’re interested in how star formation in the LMC might have been different than in the Milky Way.

A team of researchers zeroed in on the LMC’s most metal-deficient stars to find out how different.

March 29, 2024March 29, 2024 by Scott Alan Johnston

Astronomers Catch a Supernova Explode Almost in Realtime

A composite image taken with the Liverpool Telescope showing the location of SN 2023ixf, a red supergiant supernova (the most blue object in the rectangle) that occurred 22 million light-years from Earth in the Pinwheel Galaxy. Credit: E. Zimmerman et al., Weizmann Institute of Science/Liverpool Telescope.

Catching a supernova in action is tricky business. There is no way to predict them, and they don’t occur very often. Within the Milky Way they only occur about once a century, and the last one was observed in 1604.

February 15, 2024February 15, 2024 by Evan Gough

Even if We Can’t See the First Stars, We Could Detect Their Impact on the First Galaxies

Population III stars were the Universe's first stars. They were extremely massive, luminous stars, and many of them exploded as supernovae. How did they shape the early galaxies? Image Credit: DALL-E — Population III stars were the Universe's first stars. They were extremely massive, luminous stars, and many of them exploded as supernovae. Image Credit: DALL-E

For a long time, our understanding of the Universe’s first galaxies leaned heavily on theory. The light from that age only reached us after travelling for billions of years, and on the way, it was obscured and stretched into the infrared. Clues about the first galaxies are hidden in that messy light. Now that we have the James Webb Space Telescope and its powerful infrared capabilities, we’ve seen further into the past—and with more clarity—than ever before.

The JWST has imaged some of the very first galaxies, leading to a flood of new insights and challenging questions. But it can’t see individual stars.

How can astronomers detect their impact on the Universe’s first galaxies?