Supernovae are incredibly common in the universe. Based on observations of isotopes such as aluminum-26, we know that a supernova occurs on average about every fifty years in the Milky Way alone. A supernova can outshine a galaxy, so you wouldn’t want your habitable planet to be a few light years away when it goes off. Fortunately, most supernovae have occurred very far away from Earth, so we haven’t had to concern ourselves with wearing sunscreen at night. But it does raise an interesting question. When it comes to supernovae, how close is too close? As a recent study shows, the answer depends on the type of supernova.
Continue reading “You Don't Want to Be Within 160 Light-Years of a Supernova”It’s Time for Supernova Remnant Cassiopeia A to Get the JWST Treatment
Ready for another stunning image from JWST? How about a peek inside a supernova remnant? Not just any stellar debris, but a highly detailed view of the leftovers from the explosion that created Cassiopeia A. The latest image is giving astronomers an up-close and personal look at what happened to a supermassive star some 11,000 light-years away from us. It may also help answer questions about the existence of cosmic dust, particularly in the early Universe.
Continue reading “It’s Time for Supernova Remnant Cassiopeia A to Get the JWST Treatment”Did Supernovae Help Push Life to Become More Diverse?
Life on Earth has been around for a long time—at least 3.8 billion years. During that time, it evolved significantly. Why has biodiversity here changed so much? A new study proposes a startling idea. Some major diversity changes are linked to supernovae—the explosions of massive stars. If true, it shows that cosmic processes and astrophysical events can influence the evolution of life on our planet.
Continue reading “Did Supernovae Help Push Life to Become More Diverse?”The Dark Energy Camera Captures the Remains of an Ancient Supernova
The first written record of a supernova comes from Chinese astrologers in the year 185. Those records say a ‘guest star’ lit up the sky for about eight months. We now know that it was a supernova.
All that remains is a ring of debris named RCW 86, and astronomers working with the DECam (Dark Energy Camera) used it to examine the debris ring and the aftermath of the supernova.
Continue reading “The Dark Energy Camera Captures the Remains of an Ancient Supernova”JWST Sees the Same Supernova Three Times in an Epic Gravitational Lens
The NASA/European Space Agency (ESA)/Canadian Space Agency (CSA) James Webb Space Telescope (JWST) mission continues to dazzle and amaze with every image it beams back to Earth, and a recent observation depicting not one, not two, but three images of the same galaxy has been no different, as they proudly tweeted on February 28, 2023.
Continue reading “JWST Sees the Same Supernova Three Times in an Epic Gravitational Lens”Some Elements Arrived on Earth by Surfing Supernova Shock Waves
When stars die, they spread the elements they’ve created in their cores out to space. But, other objects and processes in space also create elements. Eventually, that “star stuff” scatters across the galaxy in giant debris clouds. Later on—sometimes millions of years later—it settles onto planets. What’s the missing link between element creation and deposition on some distant world?
Continue reading “Some Elements Arrived on Earth by Surfing Supernova Shock Waves”This Binary System is Destined to Become a Kilonova
Kilonovae are extraordinarily rare. Astronomers think there are only about 10 of them in the Milky Way. But they’re extraordinarily powerful and produce heavy elements like uranium, thorium, and gold.
Usually, astronomers spot them after they’ve merged and emitted powerful gamma-ray bursts (GRBs.) But astronomers using the SMARTS telescope say they’ve spotted a kilonova progenitor for the first time.
Continue reading “This Binary System is Destined to Become a Kilonova”By Looking Back Through Hubble Data, Astronomers Have Identified six Massive Stars Before They Exploded as Core-Collapse Supernovae
The venerable Hubble Space Telescope has given us so much during the history of its service (32 years, 7 months, 6 days, and counting!) Even after all these years, the versatile and sophisticated observatory is still pulling its weight alongside more recent addition, like the James Webb Space Telescope (JWST) and other members of NASA’s Great Observatories family. In addition to how it is still conducting observation campaigns, astronomers and astrophysicists are combing through the volumes of data Hubble accumulated over the years to find even more hidden gems.
A team led by Caltech’s recently made some very interesting finds in the Hubble archives, where they observed the sites of six supernovae to learn more about their progenitor stars. Their observations were part of the Hubble Space Telescope Snapshot program, where astronomers use HST images to chart the life cycle and evolution of stars, galaxies, and other celestial objects. From this, they were able to place constraints on the size, mass, and other key characteristics of the progenitor stars and what they experienced before experiencing core collapse.
Continue reading “By Looking Back Through Hubble Data, Astronomers Have Identified six Massive Stars Before They Exploded as Core-Collapse Supernovae”Hubble saw the Same Supernova at Three Different Times Thanks to Gravitational Lensing
As cosmic events go, supernova explosions epitomize the saying, “Live fast, die young, and leave a good-looking corpse.” They’re the deaths of stars so massive that they tear through their fuel in a short time. Then, they explode and create gorgeous scenes of stellar destruction. These seminal events enrich the universe with chemical elements for new generations of stars and planets.
Continue reading “Hubble saw the Same Supernova at Three Different Times Thanks to Gravitational Lensing”Hubble saw Multiple Light Echoes Reflecting off Rings of Dust From a Supernova Explosion
When stars reach the end of their life cycle, they experience gravitational collapse at their centers and explode in a fiery burst (a supernova). This causes them to shed their outer layers and sends an intense burst of light and high-energy short-wavelength radiation (like X-rays and gamma-rays) out in all directions. This process also creates cosmic rays, which consist of protons and atomic nuclei that are accelerated to close to the speed of light. And on rare occasions, supernovae can also create “light echoes,” rings of light that spread out from the site of the original explosion.
These echoes will appear months to years after the supernova occurs as light from the explosion interacts with the layers of dust in the vicinity. Using the Hubble Space Telescope (HST), an international team of astronomers was able to document the emergence and evolution of multiple light echoes (LEs). The team traced these echoes to a stripped-envelope supernova (SN 2016adj) located in the central dust lane of Centaurus A, a galaxy located 10 to 16 million light-years away in the constellation of Centaurus.
Continue reading “Hubble saw Multiple Light Echoes Reflecting off Rings of Dust From a Supernova Explosion”