Was the Moon formed after an Earth impact?

Earth's moon is not as special as you might think, because in our Solar System moons or even planets exists, that very much remind us of the Moon. Mercury, for example, or the moon of Saturn, Dione, are few bodies which strikingly resembles our moon, through color and craters.
Seeing some images made by space probes of these bodies, I often did not know what I'm looking at: the Moon or Mercury for example. This puts me on my personal thought about the theory of lunar formation, even if now is believed to have formed from an Earth collision with a smaller planet.

Because objects are so similar to our moon, I'm beginning to think that the accepted theory is not well founded. Because it is possible that it could have been formed in the early formation of the Solar System, but without a certain orbit, being attracted by Earth's gravity. It may otherwise have been even a satellite of Jupiter or Saturn, but in the chaos at the beginning, everything was possible and got stuck in the gravitational field of our planet.

Saturn's moons as Mimas, Tethys, Dione, Rhea, Enceladus or Ganymede of Jupiter, Miranda, Ariel, Umbriel, Titania, Oberon of Uranus, Mercury planet, however have striking resemblance to our moon. These are just some examples.

Mercury planet.

Dione, moon of Saturn.

Ganymede, moon of Jupiter.

Mimas, moon of Saturn.

Rhea, moon of Saturn.

Tethys, moon of Saturn.

Moons of Uranus.

Credit of the images above: NASA.

But even Jupiter or Saturn's satellites I doubt that would be composed of the same materials as of their planets, simply because they are gaseous. Isn't it possible that these dozens of satellites be only trapped in the gravity of these gas giants?

Returning to the Moon, besides this, the Moon is too large, 1/4 of the Earth, too bulky to be formed from combining the two bodies collided. This mean the Earth collided with a planet so large that would have destroyed almost all the planet that would be impossible reform in the condition it is today, and to be able to collect such material from the impact that formed our giant moon. It's only a theory, I'm not keep it as true.

The Moon is an alien with respect to Earth. it is in the "green zone" with us, but still looking like that.
I am sure that the collision theory is sustained by scientists because by collecting lunar rocks they found similarities between Earth and the Moon, but what if we are misled by the evidence? Hve we collected rocks from Mercury, or other similar bodies to our Moon? Maybe they have more in common than the Moon and the Earth.

This article has not so much attention on the internet, but if it had, I'm sure many scientists would show me the contrary by comments, but I tend to think that it would be many who would give me credit even in some respects . One thing is certain for me: the origin of the Moon has not been 100% solved . We have many surprises in the future when we will discover things that we now do not know.

Info for first 2 images of the Moon:
Magnitude: -12.14
Phase: 0.97
Distance: 398.311 km
Illuminated: 96.7% (0% = new, 100% = full)

Astronomical Instrument: Celestron C8-Newtonian telescope
Eyepiece: plossl 20mm, 2x Barlow
Mount: CG5 (EQ5)
Camera: Sony CX130
Filter: no
Date: 03/14/2014
Location: Baia Mare, Romania
Processing: FastStone Image Viewer

Posted in: Astronomy Questions and Answers