On a recent episode of "How the Universe Works" the subject was Mercury and what has been discovered since the recent Messenger probe sent there. It has been discovered that most of Mercury's mantle is missing and it was determined that it was due to a massive collision early in the history of the solar system. Since it has also been theorised that our moon was formed after a fairly large planetoid collided with the earth I am wondering if it is possible that Mercury was the culprit,

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

It doesn't seem too likely that Theia, the name given the impacting planet that is thought to have struck the Earth and created the Moon, can be identified as Mercury. Recent work on the nearly identical oxygen isotopes of Earth and Moon seem to indicate a head-on collision.

Theia was presumably destroyed at that time, its material incorporated into the primordial Earth, and Moon. Also-- Earth is said to have a larger than expected iron core, for planet of its size. This, too, suggests that the core of Theia was absorbed by Earth.

Please find a link, below, to an article with more details on the recent scientific work on the Giant Impact Hypothesis:

http://newsroom.ucla.edu/releases/moon-was-produced-by-a-head-on-collision-between-earth-and-a-forming-planet

Or perhaps both air and water for that of the Earth, if not any sand, dust, or stone, for that of both the Moon and also Mars.

For one thing still both hemoglobine which could be making up your blood, if not any iron which could be making up much of a planet, and here Mercury.

Still four small planets innermost in the solar system, and next the four gas giants as well, and the solar system is far from smooth or homogeneous, when it comes to both composition and structure.

Like a bit of sunshine when also having the oceans of Earth, also the bit of strange surface for that of Mercury, including its visible color.

If one thing is still the fact that the planets could be orbiting the sun, next no such thing as any hype or speculation for that of making it the man in the Moon either.

One of Saturn's moons is having a giant impact crater on its surface, but such a thing apparently does not affect much of other things.

https://en.wikipedia.org/wiki/Tethys_(moon)

Here perhaps easy to miss the whole fact, but here it possibly happened, and made for a bit of surprise.

New Moon birth theory.

Cheers.

Just goes to show how little is really known about the early history of our solar system.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

Just goes to show how little is really known about the early history of our solar system.

Yes. But this happened more than 4 billion years ago.
Now there is two theories to explain the origin of our moon that make sense,
Our moon was created by a hit of another "planet".
Our moon was created by giving birth from Earth.

I am well aware of the prevailing theories. It just seems to me that it is possible, however remotely, that Mercury might be the the object, that is referred to as Theia. Especially after reading of the discoveries that were made by the instruments on the Messenger probe. It is claimed that the mantle and crust of Mercury are missing, leaving the exposed core.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

This hypothesis, although not perfect, perhaps best explains the evidence

Yes. But that theory doesn't rule out other theories .

And as Bob DeWoody points out.
Where is the crust that once was on Mercury now?

Maybe the mission BepiColombo will answer some more questions.
https://en.wikipedia.org/wiki/BepiColombo

The main objectives of the mission are:[2][10]
Study the origin and evolution of a planet close to its parent star
Study Mercury as a planet—its form, interior, structure, geology, composition and craters
Investigate Mercury's exosphere, composition and dynamics, including generation and disappearance
Study Mercury's magnetised envelope (magnetosphere) - structure and dynamics
Investigate the origin of Mercury's magnetic field
Verify Einstein's theory of general relativity by measuring the parameters gamma and beta of the parameterized post-Newtonian formalism with high accuracy.[11]

The planned mission schedule is ~5 October 2018.
http://www.esa.int/Our_Activities/Space_Science/BepiColombo/BepiColombo_Factsheet