Astronomers came to the conclusion that the small moons of Pluto could have formed as a result of collision its largest satellite Charon with another celestial body, reported in an article published in The Astrophysical Journal. If the assumption is true, it will help to understand how planets are born in binary systems.
One of the most popular theories says that in the past the Pluto collided with another large celestial body, the result of which formed its largest moon Charon, and small moons Styx, nix, Kerberos and Hydra. Initially, Pluto and Charon were very close to each other and have made a revolution around a common center of mass in 1-2 days, but over time, the satellite drifted away and went to the known orbit. However, as it turned out on the modern orbits of the small moons of Pluto, scientists are not clear because of the gravitational interaction between the dwarf planet and Charon would be likely to lead to their ejection outside the system.
Bromly Benjamin (Benjamin C. Bromley) from Utah state University and Scott Kenyon (Scott J. Kenyon) from the Smithsonian astrophysical Observatory suggested an alternative version. Since all the moons of Pluto are in the same orbital plane as the dwarf planet and its largest moon, astronomers have suggested that in the past around the system could be debris disk. However, he appeared somewhat later, when Charon collided with another TRANS-Neptunian object.
To test their hypothesis, the authors conducted a simulation that showed that Charon collision with another celestial body with a radius of 30 to 100 kilometres of well explains the appearance of the Styx, nix, Kerberos and Hydra. According to the model, it could be less than a billion years after the formation of the moon. The result of the events in orbit around the system were thrown debris, which subsequently melted and formed small satellites of Pluto. Thus the system was able to avoid destabilizing orbital resonances.
If the hypothesis of scientists is correct, it may help to explain how around binary stars formed planets, since Pluto and Charon serve as a scale model of such systems.
Recently astronomers built the first geomorphological map of Charon. Thanks to her, the first time they were able to roughly describe the geological history of Charon and figure out what in the past it was the large-scale processes of cryovolcanism.