Is it also a Hill sphere/proximity to the Sun issue? From what I understand, the leading theory as to why Venus’ period of rotation is longer than its year is that this was also due to a huge collision, and that this is the leading theory for why Mercury has a huge core relative to its mantle.

the original star).An ideal example of this is the Earth, which is capable of keeping the Moon in its orbit due to excessive gravity of the Sun because it orbits within the mountainous region of the Earth. This may be due to solar winds and the condensation radii of lighter materials, where trace substances like hydrogen and methane remained in gaseous form nearer to the Sun during Mercury’s formation, and were thence swept away. The Moon on If the moon is such a common feature in the solar system, then why is it that there is no one with Mercury? This left only elements like iron and and nickel in solid form, which then coalesced to form Mercury and the other terrestrial planets.For a time in the early 1970s, astronomers thought the Mercury might have a moon.

Any moon would most likely crash into Mercury or maybe go into orbit … the parent star).