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When asked to prove the various differences between meteorites and Apollo rocks.

Posted 31 Jul 2013 at 15:28 PM by Futtock

Really? That's your response to totally obvious and easily looked up geology effects on meteorites?

Fusion crusts and the effect on helium-3/zap pits and the totally obvious signs they show to a geologist:-


"[B]Meteoroids* enter the atmosphere at speeds of many miles per second. At those tremendous speeds, the air in the path of the meteorite is severely compressed. When air is compressed rapidly, its temperature increases (like air in a bicycle tire pump). This hot air causes[/B] [B]the exterior of stony meteoroids to melt. The melted portion is so hot and fluid that it immediately ablates (sloughs off) and new material is melted underneath. A meteoroid can lose most of its mass as it passes through the atmosphere. When it slows down to the point where no melting occurs, the last melt to form cools to make a thin, glassy coating called a fusion crust. On stony meteorites, fusion crusts are seldom more than 1 or 2 mm thick. Except for some lunar meteorites (less that 1 in 1000 of all meteorites), fusion crusts are not distinctly [URL="http://meteorites.wustl.edu/id/vesicles.htm"][COLOR=#0000ff]vesicular[/COLOR][/URL] - there are no bubbles. Some fusion crusts will show flow features; others may cover [URL="http://meteorites.wustl.edu/id/regmaglypts.htm"][COLOR=#0000ff]regmaglypts[/COLOR][/URL]."[/B]

Contamination from water and atmosphere:-


"Despite their age, they are vulnerable to the terrestrial environment. [URL="http://en.wikipedia.org/wiki/Water"][COLOR=#0645ad]Water[/COLOR][/URL], [URL="http://en.wikipedia.org/wiki/Chlorine"][COLOR=#0645ad]chlorine[/COLOR][/URL] and [URL="http://en.wikipedia.org/wiki/Oxygen"][COLOR=#0645ad]oxygen[/COLOR][/URL] attack meteorites as soon they reach the ground."

Total ever found of Moon rock meteorites:-


"Since 1980, over 120 lunar meteorites representing about 60 different meteorite fall events (none witnessed) have been collected on Earth, with a total mass of over 48 kg (105.8 lb)"


It depends upon how one counts. [URL="http://meteorites.wustl.edu/lunar/moon_meteorites_list_alpha.htm"][COLOR=#0000ff]More than 170 named stones[/COLOR][/URL] have been described in the scientific literature that appear to be lunar meteorites. Other rocks that have not yet been described in the scientific literature but which might be lunar meteorites are being sold by reputable dealers. The complication is that some to many of these stones are "paired," that is, two or more of the stones are different fragments of a single meteoroid that made the Moon-Earth trip. When confirmed or strongly suspected cases of pairing are taken into account, the number of actual meteoroids reduces to about 84. Pairing has not yet been established or rejected for the many recently found meteorites, so the actual number is not known with certainty. In the [URL="http://meteorites.wustl.edu/lunar/moon_meteorites_list_alumina.htm"][COLOR=#0000ff]List[/COLOR][/URL], known or strongly suspected paired stones are listed on a single line separated by slashes. In most cases, the stones were found close together because a meteoroid broke apart upon encountering the Earth's atmosphere, hitting the ground or ice, or while traveling within the ice in Antarctica. (In the other cases, all from northern Africa, we don't know for sure where they were found.) The six [URL="http://meteorites.wustl.edu/lunar/stones/lap02205.htm"][COLOR=#0000ff]LaPaz Icefield[/COLOR][/URL] stones all have fusion crusts and the broken edges don't fit together, thus the LAP meteoroid likely broke up in the atmosphere. Among the numerous Dhofar lunar meteorite stones, [URL="http://meteorites.wustl.edu/lunar/stones/dhofar0489.htm"][COLOR=#0000ff]about 15[/COLOR][/URL] appear to all be pieces of a single meteorite."

Solar Isotopes:-


"For several reasons, we know that the lunar meteorites derive from many different impacts on the Moon. The textural and compositional variety spans, and in some ways exceeds, that of rocks collected on the six Apollo landing missions, so the meteorites must come from many locations. More importantly, it is possible to determine how long ago a rock left the Moon using [I]cosmic-ray exposure ages[/I]. 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. [B]As soon as they fall to Earth, production stops because the Earth's atmosphere absorbs nearly all cosmic rays.[/B] The radionuclides decay on Earth with no further production. The most well-know such isotope is 14C (carbon 14), which is produced from oxygen atoms in the meteoroid. Other important radionuclides produced by cosmic-ray exposure are 10Be, 26Al, 36Cl, and 41Ca. Because the various radionuclides all have different half-lives, [B]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.[/B] "

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