NASA’s Chandra Finds Unexpected Fireworks in Aftermath of Stellar Explosions

https://science.nasa.gov/missions/chandra/nasas-chandra-finds-unexpected-fireworks-in-aftermath-of-stellar-explosions/?utm_source=newsletter&utm_medium=email&utm_campaign=nn202624 The aftermath of a supernova — a stellar explosion — is typically a slowly fading cloud of hot gas. So when astronomers used NASA's Chandra X-ray Observatory to study the nearby galaxy Messier 83, they did not expect to find supernova remnants showing dramatic changes in brightness. The galaxy, located about 15 million light-years from Earth, is forming new stars at a high rate. Researchers analyzed 14 years of Chandra observations of the galaxy, collected between 2000 and 2014. Within this extensive set of data, they discovered surprising variations in the X-ray brightness of sources previously identified as supernova remnants. The researchers expected supernova remnants older than a century to fade gradually in X-rays, but the team did not anticipate seeing such dramatic changes in brightness.