The name of a hypothesized protoplanet that hit the Earth to create the moon is derived from the mythical Greek titan Theia, who gave birth to the Moon goddess, Selene. Is Selene in any relation to Hina? I’m going to go ahead and doubt that but I would love to hang out with them both and have a cocktail.
The Harvard Gazette reports – “As part of their dynamic model, Ćuk and Stewart found that a resonance between Earth’s orbit around the sun and the moon’s orbit around Earth can pass angular momentum to the sun. Furthermore, Ćuk and Stewart showed that if the Earth was fast-spinning before the impact, then a giant collision could eject enough Earth material into orbit to make the moon.”
In the animation, Earth and the smaller planet that hit Earth, named Theia, are represented by many particles with a fixed mass, shown as small balls. The color of the ball indicates the material: iron cores and rocky mantles. Before the impact, Earth’s shape is an oblate spheroid because the day is only 2.3 hours long. Video by Sarah T. Stewart