New look at the Moon’s origin
The group of American and British scientists presented to the scientific community a new hypothesis of the appearance of the moon, according to which the earth's satellite originated from a donut-shaped cloud of liquid Earth rocks.
A study, authored by astrophysicists and astronomers from Harvard, the University of California, Davis, and the University of Bristol, has been recently published in Journal of Geophysical Research.
Canonized theory says more than 4 billion years ago a planetary mass, about the size of Mars, called Theia scratched the surface of proto-planet Earth, as s result there was a powerful ejection of fragments of the both planets into Earth orbit. Those splinters subsequently formed the natural satellite - Moon.
However, according to Harvard University‘s graduate student Simon Lock, the lead author of the new paper, “Getting enough mass into orbit in the canonical scenario is actually very difficult, and there's a very narrow range of collisions that might be able to do it”.
The new study agrees that the whole process of the origin of the Moon began with a great crash that formed around the Earth the synestia - bulging vapor cloud consisting of vaporized liquid rocks and moisture. The collision was so strong that the 10% of the Earth’s rock were vaporized.
The name "synestia" is a combination of two Greek words: "SYN" (together) and "Hestia" (the Greek goddess of hearth and architecture).
At some point, under the influence of strong rotation, near the center of the synestia the liquid rocks, boring into the clot, formed the germ of the future moon, surrounded by its own steam shell under the temperature of 2-3 thousand degrees Celsius.
As the structure was cooling, condensation made the liquid rocks rushed back to Earth, but some of them was raining on the lunar germ, causing its growth. Eventually, the "donut" decreased in size, and the Moon came out of a steam cloud as a celestial body. All process took only a few tens of years, in comparison with the Earth forming about 1000 years later.
The idea of synestia, which was initially voiced as the general theory of the planet origin, contains a sufficient number of controversial points, and Simon Lock and his team still have a lot of work and computations. So, if the theory of Moon forming on the Earth’s disk, similar to Saturn, is supported by visual evidence of the existence of the ringed planets, the synestia is still visible only on lab computer displays.
