One of the weaknesses of this theory is the inability to explain the different densities of the Moon and the Earth . Planetologist William Hartmann, express doubts that two celestial bodies could have form from the same substance, but one of them, the Earth, has an iron core, and the other, the Moon, is practically absent . So, when samples of lunar soil were deliver to Earth and its composition became known, the coaccretion hypothesis was reject Capture theory The final theory of the “Big Three” is the hypothesis of the capture of the already form Moon by the Earth.
Who put forward the theory of a giant collision
It was first voic by the American astronomer Thomas El Salvador Phone Number List See (Thomas Jefferson Jackson See) in . According to this hypothesis, a celestial body flew past the Earth, which the Earth pull into its orbit by gravitational forces. The moon in this version is not a fragment of the Earth or a “sister”, but a “guest” who happen to be near the Earth. This theory can be confirm by the fact that the planet Mars, probably in this way, acquir its satellites – Deimos and Phobos. They can be “alien” asteroids, just like the Moon. It is not easy to create such a stable system.
It is similar to the capture theory
However this theory also has weaknesses: celestial USA CFO bodies-“aliens” often have a bizarre shape, and not spherical, like the Moon. And their trajectories are far from the circular orbit in which the Moon is currently moving. The hypothesis, known in English as the Many-moons Theory, was describ by the American geophysicist Gordon JF MacDonald in . – with the only difference that it was easier for the Earth to “capture” several smaller celestial bodies than one large one. According to Macdonald, several celestial bodies attract to the Earth could eventually form one large Moon.