"Pluto and Charon's formation has puzzled scientists for years," said lead researcher Adeene Denton. By considering the structural integrity of ice and rock in smaller, colder bodies, the team uncovered a scenario where the impact did not lead to massive deformation. Instead, the two bodies temporarily merged into a snowman-like structure before separating into their current configuration.

Advanced simulations demonstrated that, unlike larger planetary bodies, neither Pluto nor proto-Charon underwent significant deformation during the collision. Senior author Erik Asphaug commented, "This model not only explains Charon's capture but also accurately predicts its current orbit."

The findings indicate that Pluto and Charon retained much of their original composition during their formation, challenging earlier models that proposed extensive mixing and deformation. Furthermore, the separation and tidal friction between the two bodies during this process generated substantial internal heat. This heating may have enabled Pluto to develop a subsurface ocean, sidestepping the need for early solar system conditions high in radioactive material-a key issue for planetary scientists.

The research team intends to further investigate the influence of tidal forces on the early evolution of Pluto and Charon. They will also explore how this scenario aligns with Pluto's present-day geological features and whether similar processes could explain the formation of other binary systems.

Research Report:Capture of an ancient Charon around Pluto

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