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I don't have much knowledge of Astronomy but today I was googling randomly and found an article, according to which:

  1. The moon is of the wrong size for its current orbit.
  2. The moon rings like a bell when hit by an object, which could signal that it's hollow.
  3. Metal shavings were found in samples taken by the Apollo crew.
  4. UFO sightings were common on NASA moon missions.
    All these phenomena and more point toward the suggestion that the moon is actually an artificially created spaceship. It's a bit far fetched, but it's odd that astronomers have been discouraged from testing this theory.

Can this theory be true?

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Without going to much into detail for now: What is your source? (I call BS by the way.) –  Alexander Janssen Jul 22 '14 at 8:12
@Alexander Janssen : www.gizmopod.com/gallery/1893/which-mind-blowing-mysteries-are-unsolved –  ashu Jul 22 '14 at 9:15

1 Answer 1

up vote 5 down vote accepted
  1. Orbital radius depends on speed of the body. Size is largely irrelevant. Imagine a space craft and much larger space station, able to orbit meters apart at the same speed, with engines switched off. An astronaut going on a spacewalk would be launched away from the station, being much smaller and so on wrong orbit. No. It's as relevant as "Boeing 747 shouldn't be able to fly because it's painted the wrong color." False and based on wrong premise.

  2. For anything to ring you need atmosphere, a medium for sound to travel through. Moon, floating in vacuum, doesn't ring, nor create any other sound for that matter. Even the most powerful meteor impacts are entirely silent. False and based on wrong premise.

  3. Countless iron meteorites hit the surface of the Moon, often shattering on impact. Specks of iron are very common in lunar soil, and I have no doubt it's entirely possible shavings-shaped pieces of lunar meteor might have found their way into the samples. Likely True and nothing odd about it.

  4. ...how does that even relate?

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How did I miss vaccum! -_- damn! –  ashu Jul 22 '14 at 12:06
@ashu Sound travels through solids just fine, so it's quite non-obvious that "for anything to ring you need an atmosphere". Impacts create sound waves in the moon, which can reflect several times from the inner surface. Whether or not that counts seems to me to be more a question of how one interprets the phrase "ringing like a bell" in the first place: there are similarities and there are differences, and which count as important and to what extent is rather vague. –  Stan Liou Jul 22 '14 at 15:30
@StanLiou: Nevertheless, Moon doesn't reverb as if it was hollow. –  SF. Jul 22 '14 at 15:56
@SF.: Good point--you're right, the conclusion is unchanged. Though the seismic disconfirmation of hollow moon would be a different issue than what was addressed here. –  Stan Liou Jul 22 '14 at 16:01
@SF - the wording is unfortunate. The Moon does "ring" - seismic waves are created by large impacts and can be detected by seismographs on the lunar surface. You are correct that it does not "ring" as if it was hollow, but vibrations are produced and are registered - and are compatible with the fact that the Moon is a solid body. You may want to edit the wording a bit. –  Florin Andrei Jul 22 '14 at 18:19

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