Blanet

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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[edit]

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[edit]

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

In fiction[edit]

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[edit]

  1. ^ Letzter, R. (6 August 2020). "Thousands of Earthlike 'blanets' might circle the Milky Way's central black hole". Space.com. Retrieved 2020-08-08.
  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. arXiv:1909.06748. Bibcode:2019ApJ...886..107W. doi:10.3847/1538-4357/ab4cf0.
  3. ^ a b 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. arXiv:2007.15198. Bibcode:2021ApJ...909...96W. doi:10.3847/1538-4357/abd40a. S2CID 220870610.
  4. ^ Starr, M. (3 August 2020). "We Have Ploonets. We Have Moonmoons. Now Hold Onto Your Hats For... Blanets". ScienceAlert. Retrieved 2020-08-08.
  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'". The Next Web. Retrieved 2020-08-08.