Chandra Detects Surviving Stars Fueling X-ray Flares in M83
NASA's Chandra X-ray Observatory studied the star-forming galaxy Messier 83 over 14 years and found that about half of the 22 X-ray sources tied to supernova remnants vary dramatically in brightness, a surprise that points to a population of stellar survivors in high-mass X-ray binaries with compact remnants accreting from their companion stars; alternative explanations include fallback of exploded material. This may be common in star-forming galaxies, with similar variability seen in M51.