A cosmic blowtorch might be triggering stellar explosions in M87
Deep within the galaxy M87, a supermassive black hole launches a massive jet of plasma. While anything caught directly in this beam would be destroyed, astronomers have discovered that stars in the nearby neighborhood are experiencing a sudden surge in violent eruptions.
Using NASA’s Hubble Space Telescope, astronomers have identified a surprising correlation between the 3,0-light-year-long plasma jet of the M87 black hole and an increased rate of novae. During a recent 9-month survey, researchers found twice as many nova eruptions occurring near the jet's trajectory as in other parts of the galaxy. This finding, led by Alec Lessing of Stanford University, suggests that the jet's presence fundamentally alters the behavior of nearby stellar systems.
A nova occurs in a binary system where an aging, swollen star spills hydrogen onto a dense, burned-out white dwarf. As the white dwarf accumulates a mile-deep layer of this hydrogen, it eventually reaches a tipping point and explodes with the force of a nuclear bomb. Crucially, the white dwarf survives the blast, continuing to siphon fuel and restarting the cycle. While the jet itself is too energetic to allow stars to survive, the 'dangerous neighborhood' just outside the beam appears to be a hotbed for these outbursts.
The exact mechanism remains a mystery, but researchers are investigating two primary theories. One possibility is that the jet 'snowplows' hydrogen fuel onto the white dwarfs, or that the pressure from the jet's light increases the mass transfer rate. Another hypothesis suggests the jet might heat companion stars, causing them to overflow more hydrogen; however, calculations indicate this heating is likely insufficient. As of now, the discovery indicates a significant gap in our understanding of how supermassive black hole jets interact with their galactic surroundings.
Source: Hubble Spots Black Hole Beam Causing Stellar Eruptions
