Hidden black hole may explain star's 27 repeated eruptions: NASA

NASA's Chandra X-ray Observatory suggests a hidden black hole or neutron star is behind giant star AT 2016blu's 27 repeated eruptions. The companion swoops past, stealing material and triggering X-ray bursts. The star survived each blast. The 15-year study involved 30+ amateur astronomers and could explain pre-supernova behavior in massive stars.