Produced by: Tarun Mishra Designed by: Manoj Kumar
Astronomers have discovered the first known triple black hole system, where a black hole is feeding on a companion star while being orbited by a third, more distant star. This system is located within the Milky Way in the V404 Cygni region, around 8,000 light-years from Earth.
Credit : NASA
The discovery raises the possibility that the black hole formed through a direct collapse rather than a violent supernova explosion. This suggests that the black hole may have had a less energetic birth, as a supernova would have likely ejected the third star from the system.
Led by Kevin Burdge from MIT, the team made the discovery while studying the previously known X-ray binary involving the black hole and its companion star. A deeper investigation revealed the presence of the distant third star, forming the first known triple black hole system.
The fact that the third star remains bound to the system suggests the black hole received a low-energy natal kick during its formation. This contradicts typical theories that black holes form from the violent death of massive stars, which usually impart a strong kick to surrounding objects.
The close star orbits the black hole every 6.5 Earth days, while the newly discovered distant star has an extremely wide orbit, completing one revolution around the black hole every 70,000 Earth years. This vast separation adds to the uniqueness of the system.
To confirm the third star’s presence, the team used data from the Gaia space telescope, which tracked the stars' movements over a decade. The analysis showed that the third star’s motion was consistent with being gravitationally bound to the black hole.
Running thousands of simulations, the researchers found that the only likely way the system could remain intact after the black hole's formation is through direct collapse, avoiding the explosive energy release of a supernova.
The third star is evolving into a red giant, providing clues about the system's age. The team estimates that the system is approximately 4 billion years old, making it the first time such an aging process has been applied to a black hole system. Further investigations are planned to learn more about this rare triple configuration.