Unknown X-ray 'bursts' in different galaxies spotted
Astronomers with NASA's Chandra X-ray Observatory have spotted two X-ray sources erupting in two different galaxies, becoming 100 times brighter in less than a minute. One of the 'ultraluminous' X-ray sources was the brightest ever observed in an elliptical galaxy. Scientists have hypothesised that the phenomenon could be caused by star matter rapidly falling into an intermediate-mass black hole.