The cosmos is a mysterious place. Researchers have discovered that black holes can revive dead stars. More specifically, only “close encounters” with medium-sized black holes could temporarily bring dead stars back to life. That, at least, is the conclusion of new research that was issued in the Astrophysical Journal.
Medium-sized black holes can revive dead stars for a few seconds
A team of astronomers performed a series of computer simulations to establish what occurs when a scorched celestial body called a white dwarf goes past a medium-sized black hole of up to 10,000 times the mass of the Sun.
The scientists found that the powerful gravitational pull of the black hole can so dramatically stretch and distort the inert core of the white dwarf that the processes of nuclear fusion can restart for some seconds, transforming helium, carbon, and oxygen into heavier compounds, such as iron.
These “tidal disruption events” can also produce gravitational waves, the waves in space-time foreseen by Albert Einstein over 100 years ago and directly observed by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015.
The new study paves the way to better methods to monitor medium-sized black holes
The new findings point to a new potential approach to better monitoring of medium-sized black holes, seemingly surprisingly challenging to investigate. Astronomers have encountered many small black holes (of about one stellar mass), and they know that supermassive black holes with millions or billions of solar masses are lurking in the core of most galaxies if not all.
“It is essential to know how many intermediate black holes there are, as this will help answer the question of where supermassive black holes come from. Finding black holes of intermediate mass through tidal disruption events would be a tremendous advance,” said Chris Fragile, one of the co-authors of the recent study.