Astronomers using the Hubble Space Telescope have made a startling discovery: a supermassive black hole in the galaxy M87 appears to be triggering nearby stars to explode. The black hole, with a mass 6.5 billion times that of the sun, is ejecting a powerful 3,000-light-year-long jet of flaming plasma. This “blowtorch-like” jet, while dangerous to any cosmic objects in its path, is also affecting nearby star systems, causing explosions known as novas.
Novas typically occur in binary star systems, where a white dwarf — the remains of a dead star — steals hydrogen fuel from a companion star. This causes the white dwarf to explode like a nuclear bomb. However, observations near the M87 jet have revealed that novas are happening twice as frequently in nearby systems compared to the wider galaxy.
The exact mechanism behind this phenomenon is not yet clear, and it poses a fascinating mystery for scientists. Lead researcher Alec Lessing from Stanford University suggests that the black hole’s jet may be accelerating the transfer of hydrogen onto the white dwarfs, potentially triggering these novas more often. However, whether this is due to physical pushing or pressure from light emitted by the jet remains unknown.
The results, which were made available on the pre-print service arXiv on August 14, imply that our present knowledge of the interaction between black hole jets and their surrounds is lacking in some way. Astronomers have plenty of opportunity to investigate the nearly daily nova eruptions in M87, but more data are required to solve this cosmic enigma.
