A less powerful black hole can clean up the environment after all

A team of international astronomers, led by Dutch scientists, discovered that even weak jet streams from low-active black holes can be used as a type of leaf blower to clean certain parts of a galaxy. In just a few million year, the black hole observed removed approximately 75% of the cool gas in the central regions. This likely stops the formation stars. The journal will publish the results of the researchers on Thursday Astronomy of Nature.

Astronomers have assumed that star formation from within the galaxy is stopped by only strong radiation black holes. This is because the black holes destroy gas, which is the building block of stars. However, it is not clear if galaxies with weakly radiating black holes are also hindered from growing.

Radio emitter

Astronomers have now discovered a smaller black hole that is cleaning up its surroundings. This low-power blackhole is located in the constellation Perseus, in the galaxy of B2 0258+35. It doesn’t emit any strong radiation, but it has radio plasma jets which are brighter than black holes that emit visible or ultraviolet light.

The gas at B2 0258+35 gets blown away at a steady speed of 500 km per second. It weighs between five and ten solar masses per annum, and takes about a million years to evaporate. The gas is not moving fast enough for it to escape the reach of the galaxy. It eventually sinks back and ends at the edges. It cannot then form new stars.

Growth inhibitor

Suma Murthy, principal investigator (working at ASTRON as well as at the Kapteyn Institute of University of Groningen during this research), said, “That low-power radar jets have also been discovered to clean a galaxie is extraordinary.” “A large number of radio emitters are relatively silent. They were believed to play no important role in growth inhibition. These radio-emitters are weak and can actually inhibit growth, according to our results. This will be an important factor in modeling the evolution of galaxies.

The NOEMA telescopes were used by the researchers to make their observations in November 2020 and October 2020. NOEMA stands to represent Northern Extended Millimetre Array. It is a collection radio dishes located at approximately 2500m in the French Alps. Computer simulations had predicted Murthy’s observations and those of her colleagues.

Murthy submitted her Ph.D. dissertation at the University of Groningen in February. Murthy is now a postdoctoral researcher at JIVE, a European institute in Dwingeloo, which coordinates the cooperation among radio telescopes around the globe.