Astronomers found the furthest supermassive black hole duo. They were merging when the cosmos was 740 million years old.
The light of ZS7 traveled nearly 13 billion years to reach us, and the measurements are revealing how supermassive black holes grow to their huge dimensions.
Not that these two dark holes are little. They are already 10 times heavier than Sagittarius A*, the Milky Way's supermassive black hole. One of them was directly estimated to weigh 50 million times the Sun by the astronomers.
Co-author Professor Roberto Maiolino of the Kavli Institute for Cosmology stated, “The mass of the other black hole is likely similar, although it is much harder to measure because this second black hole is buried in dense gas.”
JWST's extraordinary power enabled this discovery. An infrared satellite telescope detected the characteristics of a supermassive black hole accreting materials. Ground-based telescopes cannot see such signatures.
“We found evidence for very dense gas with fast motions near the black hole, as well as hot and highly ionized gas illuminated by the energetic radiation typically produced by black holes in their accretion episodes,” said lead author Dr. Hannah Übler of Cambridge's Cavendish Laboratory and the Kavli Institute for Cosmology
These indicate the two black holes' activity. JWST saw details of ZS7 that showed it is an interactive system that will merge into a larger object.
Astronomers can better grasp how supermassive black holes become billions of times the mass of our Sun through such observations. JWST has found numerous early, large supermassive black holes. The new findings suggest an alternative explanation for their massive size and growth.
“Our findings suggest that merging is an important route through which black holes can rapidly grow, even at cosmic dawn,” said Übler.
The planned gravitational observatory LISA will measure supermassive black hole merger gravitational waves. Launch is expected in the 2030s.