Supermassive Black Hole Contributing to Star Formation in a Dwarf Galaxy

Black holes are often described as supervillains of the universe, tearing apart stars, consuming anything that gets too close to them, and trapping light.

However, detailed evidence from NASA’s Hubble Space Telescope shows that black holes are not always violent and destructive, and instead, appear to be capable of forming stars, not just eating them.

Nasa’s Hubble Space Telescope spotted one such black hole in the galaxy known as Henize 2-10, which is 30 million lightyears away.

Amy Reines, the researcher who published the first evidence of a black hole in the galaxy in 2011, was also the lead scientist on the new paper.

“From the beginning I knew something unusual and special was happening in Henize 2-10, and now Hubble has provided a very clear picture of the connection between the black hole and a neighboring star forming region located 230 light-years from the black hole,” she said.

Hubble imaging and spectroscopy of the dwarf starburst galaxy Henize 2-10 clearly show a gas flow extending from the black hole into a bright stellar birth region like an umbilical cord, causing the already dense cloud to form star clusters.

In bigger galaxies, material that falls towards the black hole is torn up by its magnetic fields, which create blasts of plasma that move at almost the speed of light. Any gas cloud that is caught in that jet would be heated to much to ever create stars.

A pullout of the central region of dwarf starburst galaxy Henize 2-10 traces an outflow,

or bridge of hot gas 230 light-years long,

connecting the galaxy’s massive black hole and a star-forming region

The black hole in the dwarf galaxy Henize 2-10 is smaller and the material that flows out of it does so more gently, however. That means that the gas was compressed in the right way to help form stars, not stop them from doing so.

“At only 30 million light-years away, Henize 2-10 is close enough that Hubble was able to capture both images and spectroscopic evidence of a black hole outflow very clearly. The additional surprise was that, rather than suppressing star formation, the outflow was triggering the birth of new stars,” said Zachary Schutte, Reines’ graduate student and lead author of the new study.

The new study of the black hole by Hubble could also help provide better detail on how such supermassive black holes are formed. Because it has stayed small, it could offer a picture of what other – now bigger – black holes looked like when they were younger, and how they might form and grow.

A paper describing the findings, ‘Black-hole-triggered star formation in the dwarf galaxy Henize 2-10’, is published today in Nature.

Sources

https://www.nasa.gov/feature/goddard/2022/hubble-finds-a-black-hole-igniting-star-formation-in-a-dwarf-galaxy