Astronomy:Blanet

From HandWiki
Short description: Hypothetical planet that orbits a black hole

A blanet is a member of a hypothetical class of exoplanets that directly orbit black holes.[1]

Blanets are fundamentally similar to other planets; they have enough mass to be rounded by their own gravity, but are not massive enough to start thermonuclear fusion and become stars. In 2019, a team of astronomers and exoplanetologists showed that there is a safe zone around a supermassive black hole that could harbor thousands of blanets in orbit around it.[2][3]

Etymology

The team led by Keiichi Wada of Kagoshima University in Japan has given this name to black hole planets.[4] The word is a portmanteau of black hole and planet.

Formation

Blanets are suspected to form in the accretion disk that orbits a sufficiently large black hole.[3][5]

In fiction

In the episodes The Impossible Planet and The Satan Pit (both 2006) of television series Doctor Who, the plot of the episode takes place on the titular “impossible planet”, a barren blanet called Krop Tor orbiting a black hole called K37 Gem 5. In Interstellar (2014), two of the 3 terrestrial planets orbiting supermassive black hole Garguantua are proper blanets. The other one orbits a main-sequence star named Pantagruel.

References

  1. Letzter, R. (6 August 2020). "Thousands of Earthlike 'blanets' might circle the Milky Way's central black hole". https://www.space.com/black-hole-planets-blanets.html. 
  2. Wada, K.; Tsukamoto, Y.; Kokubo, E. (26 November 2019). "Planet Formation around Supermassive Black Holes in the Active Galactic Nuclei". The Astrophysical Journal 886 (2): 107. doi:10.3847/1538-4357/ab4cf0. Bibcode2019ApJ...886..107W. 
  3. 3.0 3.1 Wada, K.; Tsukamoto, Y.; Kokubo, E. (2021). "Formation of "Blanets" from Dust Grains around the Supermassive Black Holes in Galaxies". The Astrophysical Journal 909 (1): 96. doi:10.3847/1538-4357/abd40a. Bibcode2021ApJ...909...96W. 
  4. Starr, M. (3 August 2020). "We Have Ploonets. We Have Moonmoons. Now Hold Onto Your Hats For... Blanets". https://www.sciencealert.com/we-have-ploonets-we-have-moonmoons-now-hold-onto-your-hats-for-blanets. 
  5. Greene, T. (2020-08-04). "Scientists: What if black holes had a safe zone where little planets could live? Let's call them 'blanets'". https://thenextweb.com/insider/2020/08/04/scientists-what-if-black-holes-had-a-safe-zone-where-little-planets-could-live-lets-call-them-blanets/.