Controversial study claims supermassive black holes could create planets bigger than Earth

Two scientists claimed in a new study that it is possible for the dust clouds surrounding supermassive black holes to create planets

Two scientists from Japan carried out a new study claiming that large planets can form around and orbit supermassive black holes. The main point of their study goes against the common scientific belief that planets can only be found near their host stars such as the Sun.

The findings of the new study, which was submitted for publication in the Astrophysical Journal, are based on the idea that stars are enclosed by a protoplanetary disk filled with dust and other cosmic debris. Theoretically, as these clouds of dust and other particles orbit the star, they fuse together to create larger cosmic bodies such as planets.

Black hole
This artist's concept illustrates a supermassive black hole with millions to billions times the mass of our sun. Supermassive black holes are enormously dense objects buried at the hearts of galaxies. (Smaller black holes also exist throughout galaxies.) In this illustration, the supermassive black hole at the center is surrounded by matter flowing onto the black hole in what is termed an accretion disk. This disk forms as the dust and gas in the galaxy falls onto the hole, attracted by its gravity. NASA/JPL-Caltech

Accretion Disks Of Supermassive Black Holes

According to the authors of the new study, stars are not the only massive objects in space that have disks around them. They pointed out that supermassive black holes are surrounded by accretion disks that contain dust and various cosmic materials. For the study's co-author, Keiichi Wada of the Kagoshima University, the dust found in accretion disks could also clump together to form planets.

Once these planets have been formed, they will be drawn by the gravitational force of the black hole. This means they would eventually orbit the black hole, just like how planets go around their host stars. "With the right conditions, planets could be formed even in harsh environments, such as around a black hole," Wada said in a press release.

Ideal Conditions for Planet Formation

For Wada and his colleague, the right conditions refer to the cool temperature within the protoplanetary disk. In stars, regions within the disk with lower temperatures allow dust particles with ice mantles to accrete or clump together. Objects within these regions will continue to grow in size through accretion until they become planets.

As for supermassive black holes, they are known to have disks that are significantly more massive than those of stars as big as the Sun. Due to the density of a black hole's disk, it is able to prevent intense radiation from penetrating. This causes low-temperature regions within the disk to emerge.

snow sunscreen
This illustration shows the seething hot planet Kepler-13Ab that circles very close to its host star, Kepler-13A. On the nighttime side the planet's immense gravity pulls down titanium oxide, which precipitates as snow. Seen in the background is the star's binary companion, Kepler-13B, and the third member of the multiple-star system is the orange dwarf star, Kepler-13C. NASA, ESA, and G. Bacon (STScI)

Supermassive Black Holes With Orbiting Planets

As the objects within the cold regions of a black hole's disk becomes bigger, it eventually turns into a planet. Due to the amount of debris within the accretion disk, the researchers noted that supermassive black holes are capable of creating planets bigger than Earth. Once the planets have been created, they would stay within the black hole's orbit, creating a cosmic structure similar to a solar system.

"Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole," Eiichiro Kokubo of the National Astronomical Observatory of Japan said.

Related topics : Space