NASA's Swift Telescope Captures Rogue Black Hole Obliterating A Star In Deep Space
Supermassive black holes almost universally anchor the centers of galaxies, where their immense gravity dominates surrounding celestial traffic. Yet theoretical models have suggested that violent galactic mergers could kick these gravitational giants literally out into space. When smaller galaxies crash into larger ones, or when three or more supermassive black holes engage in a gravitational tug-of-war, the lightest among them can be flung into orbit and left to wander in relative isolation. Because black holes emit no light of their own, these outcast leviathans remain completely invisible, until something like a star strays too close.
Such is the case that occurred in the WISEA J014656.04-152214.7 galaxy, located in the constellation Cetus. As the target star drifted toward the roughly one-million-solar-mass black hole, the extreme tidal forces proceeded to stretch and rip the star apart. The stellar material was then heated up into a bright disk that launched an equally bright relativistic jet for anyone looking hard enough.
Initially flagged by the Zwicky Transient Facility at Palomar Observatory in Southern California, the event stood out from the half-million nightly flashes scanned by wide-field survey telescopes. An AI algorithm developed by researchers at the University of Maryland and NASA’s Goddard Space Flight Center spotted the telltale light curve of a star-shredding explosion happening tens of thousands of light-years away from its galactic center.
Follow-up observations with NASA’s Swift’s ultraviolet/optical telescope measured the glowing stellar gas reaching temperatures of roughly 54,000 degrees Fahrenheit (30,000 degrees Celsius). At its peak, the feeding frenzy radiated with the luminous intensity of approximately 10 billion suns, temporarily outshining its entire host galaxy.
This discovery is the furthest off-center tidal disruption event ever confirmed, proving that massive black holes can indeed lurk unnoticed in the quiet suburbs of galaxies. Up until recently, scientists had focused their searches for star-shredding events exclusively within galactic centers. As next-gen facilities like the Vera C. Rubin Observatory in Chile and NASA's Nancy Grace Roman Space Telescope come online, perhaps researches will be able to find and track a bigger census of the universe's wandering black holes.
