Supernovas & Supernova Remnants

A quarter of a century ago, NASA released the “first light” images from the agency’s Chandra X-ray Observatory. This introduction to the world of Chandra’s high-resolution X-ray imaging capabilities included an unprecedented view of Cassiopeia A, the remains of an exploded star located about 11,000 light-years from Earth. Over the years, Chandra’s views of Cassiopeia A have become some of the telescope’s best-known images.

To mark the anniversary of this milestone, new sonifications of three images — including Cassiopeia A (Cas A) — are being released. Sonification is a process that translates astronomical data into sound, similar to how digital data are more routinely turned into images. This translation process preserves the science of the data from its original digital state but provides an alternative pathway to experiencing the data.

The supernova remnant 3C 58 contains a spinning neutron star, known as PSR J0205+6449, at its center. Astronomers studied this neutron star and others like it to probe the nature of matter inside these very dense objects. A new study, made using NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton, reveals that the interiors of neutron stars may contain a type of ultra-dense matter not found anywhere else in the Universe.

In this image of 3C 58, low-energy X-rays are colored red, medium-energy X-rays are green, and the high-energy band of X-rays is shown in blue. The X-ray data have been combined with an optical image in yellow from the Digitized Sky Survey. The Chandra data show that the rapidly rotating neutron star (also known as a “pulsar”) at the center is surrounded by a torus of X-ray emission and a jet that extends for several light-years. The optical data shows stars in the field.

In the year 1181 a rare supernova explosion appeared in the night sky, staying visible for 185 consecutive days. Historical records show that the supernova looked like a temporary ‘star’ in the constellation Cassiopeia shining as bright as Saturn.

Ever since, scientists have tried to find the supernova’s remnant. At first it was thought that this could be the nebula around the pulsar — the dense core of a collapse star — named 3C 58. However closer investigations revealed that the pulsar is older than supernova 1181.

In the last decade, another contender was discovered; Pa 30 is a nearly circular nebula with a central star in the constellation Cassiopeia. It is pictured here combining images from several telescopes. This composite image uses data across the electromagnetic spectrum and shows a spectacular new view of the supernova remnant. This allows us to marvel at the same object that appeared in our ancestors’ night sky more than 800 years ago.

This composite image of the Manatee Nebula captures the jet emanating from SS 433, a black hole pulling material inwards that is embedded in the supernova remnant which spawned it. Radio emission from the supernova remnant are blue-green, whereas the X-ray from IXPE, XMM-Newton and Chandra are highlighted in bright blue-purple and pink-white set against a backdrop of infrared data in red. The black hole emits twin jets of matter traveling in opposite directions at nearly the speed of light.

These jets distort the remnant’s shape into one astronomers dubbed the Manatee. The jets become bright about 100 light-years away from the black hole, where particles are accelerated to very high energies by shocks within the jet. The IXPE data shows that the magnetic field, which plays a key role in how particles are accelerated, is aligned parallel to the jet — aiding our understanding of how astrophysical jets accelerate these particles to high energies.

For the first time astronomers have combined data from NASA’s Chandra X-ray Observatory and James Webb Space Telescope to study the well-known supernova remnant Cassiopeia A (Cas A). As described in our latest press release, this work has helped explain an unusual structure in the debris from the destroyed star called the “Green Monster”, first discovered in Webb data in April 2023. The research has also uncovered new details about the explosion that created Cas A about 340 years ago, from Earth’s perspective.

When the object now called SN 1006 first appeared on May 1, 1006 A.D., it was far brighter than Venus and visible during the daytime for weeks. Astronomers in China, Japan, Europe, and the Arab world all documented this spectacular sight, which was later understood to have been a supernova. With the advent of the Space Age in the 1960s, scientists were able to launch instruments and detectors above Earth's atmosphere to observe the Universe in wavelengths that are blocked from the ground, including X-rays. The remains of SN 1006 was one of the faintest X-ray sources detected by the first generation of X-ray satellites.

This new image shows SN 1006 from two of NASA’s current X-ray telescopes, the Chandra X-ray Observatory and Imaging X-ray Polarimetry Explorer (IXPE). In the full image of SN 1006, red, green, and blue show low-, medium-, and high-energy detected by Chandra. The IXPE data, which measure the polarization of the X-ray light, have been added in the upper left corner of the remnant in purple. The lines in that corner represent the direction of the magnetic field.

Ian Brunton.

We welcome Ian Brunton, a research scientist currently at NASA Johnson Space Center in the Astromaterials Research and Exploration Science Division as our guest blogger. In this post, he describes his team’s work below on the effects that a nearby supernova may have on an Earth-like planet and its biosphere. Ian first became involved with this area of research as an astronomy student of Brian Fields at the University of Illinois. He will soon be continuing his academic studies as a PhD student at Caltech in the Division of Geological and Planetary Sciences.

Much has been said about the extraordinary advancements throughout the field of astronomy, particularly regarding the innovative ways in which we can now observe the universe across the electromagnetic spectrum. Chandra has of course been one of the instruments at the forefront of this exploration for the last couple of decades, illuminating the universe in the X-ray band. These new ways of looking at our universe have served to confirm, alter, or entirely upend our prior notions of certain astrophysical processes.

What I personally find most intriguing is how these new observations can then be integrated into the knowledge and pursuits of other scientific disciplines, be it planetary science, atmospheric chemistry, geology, etc.

One of the most fascinating processes (if I may say so myself…) that orbital X-ray telescopes are especially handy for are supernovae, i.e., exploding stars! I’ll elaborate a bit on exactly why below, but first, some background on nearby supernovae and Earth is needed since our project really builds upon a lot of previous work in the field.

Everyone loves a good astronomical explosion, and supernovae — typically characterized by the wondrous spectacle of their initial outbursts — are some of the best explosions in the known universe. In the blink of an eye, these monstrous events can outshine the entire combined output of stars in a galaxy, launching neutrinos, photons, and stellar material out into the abyss of the interstellar medium.