Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: CliffordK on 16/07/2012 09:37:38

Title: Are there meteorites broken from Earth?
Post by: CliffordK on 16/07/2012 09:37:38
There are Martian Meteorites & Lunar Meteorites.
Are there "Earth" crust meteorites?  From the Theia impact, or other impacts?

If the moon is made of Earth Crust, then would Earth Crust meteorites be any different from lunar meteorites?
Title: Re: Are there meteorites broken from Earth?
Post by: RD on 16/07/2012 12:07:47
If the moon is made of Earth Crust, then would Earth Crust meteorites be any different from lunar meteorites?

Possibly radiologically different  ...

Quote
it is possible to determine how long ago a rock left the Moon using cosmic-ray exposure ages. Small rocks on the surface of the Moon and in orbit around the Sun or Earth are exposed to cosmic rays. The cosmic rays are so energetic that they cause nuclear reactions in the meteoroids that change one nuclide (isotope) into another. Some of those nuclides produced are radioactive. As soon as they fall to Earth, production stops because the Earth's atmosphere absorbs nearly all cosmic rays. The radionuclides decay on Earth with no further production ... Because the various radionuclides all have different half-lives, it is often possible to tell how long a rock was exposed on or near the surface of the Moon, how long it took to travel to Earth, and how long ago it fell.
http://meteorites.wustl.edu/lunar/moon_meteorites.htm