Tidally detached exomoon

Tidally detached exomoons, also known as orphaned exomoons[1] or ploonets,[2] are hypothetical exoplanets that were formerly exomoons of another planet, before being ejected from their orbits around their parent planets by tidal forces during planetary migration, and becoming planets in their own right.[3][4] As of 2019, no tidally detached moons have yet been definitively detected, but they are believed to be likely to exist around other stars, and potentially detectable by photometric methods. Researchers at Columbia University have suggested that a disrupting detached exomoon may be causing the unusual fluctuations in brightness exhibited by Tabby's Star.[5]

The "charmingly goofy" term "ploonet", used in a paper published in the Monthly Notices of the Royal Astronomical Society,[2][6] has received attention from mainstream media sources.[2][7][8][9]