Massive Exoplanets Could Form Around Supermassive Black Holes

• A new study suggests that supermassive black holes (SMBHs) can host giant planets in their accretion disks, under specific conditions. The research, published in The Astrophysical Journal, finds that outer regions of AGN disks can support dust coagulation and formation of planetesimals with masses exceeding that of Jupiter, up to and above the hydrogen-burning limit. The mechanism involves streaming instability, where solid matter drags gas along, removing the headwind that would otherwise cause material to spiral into the star.
• The authors predict a population of exotic objects directly formed above the hydrogen-burning limit, yet of pure dust. These objects, called "degenerate lava drops," orbit the AGN and could eventually transition into stars or black holes. The study highlights that the outer regions of AGN disks are a compelling physical analog to protostellar disks, albeit on vastly larger timescales.
• The research suggests that AGN disks could be sites for the formation of many astrophysically interesting objects, from Jupiter-mass planets to stars and intermediate-mass black holes. The findings indicate that the outer regions of AGN disks are favorable for the growth and formation of such objects, with the potential for up to tens of millions of Jupiter-mass planets and a potential IMBH formation channel.

AI-generated summary of the original article — see the source for the full story.