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Earth's Oldest Known Rock Was Found On the Moon (popularmechanics.com)
schwit1 quotes Popular Mechanics: A lot of the rocks we have on Earth are pretty old, but none of them were around when our planet was first formed. The Earth itself is around 4.5 billion years old, and the oldest rocks we've ever found are a little over half that age. That seems to have changed, however, because a group of scientists recently announced they've found a rock that formed only half a billion years after the Earth itself. The twist is that this particular rock wasn't discovered on Earth at all. It was found on the moon.
The rock itself was discovered decades ago by the Apollo 14 crew. The Apollo missions brought back a whole lot of rock samples, and scientists have been methodically analyzing them ever since. This one seems to have been somewhere near the end of the list, but it may be the most interesting one ever found.
According to the analysis, this rock formed somewhere between 4 and 4.1 billion years ago, about 12.4 miles beneath the Earth's crust. Researchers knew it came from the Earth based on the amount of various minerals like quartz and feldspar, which are common on Earth but rare on the Moon. They could tell how deep it was based on a molecular analysis of the rock, which can tell the researchers what temperature the rock was at when it formed.
The rock itself was discovered decades ago by the Apollo 14 crew. The Apollo missions brought back a whole lot of rock samples, and scientists have been methodically analyzing them ever since. This one seems to have been somewhere near the end of the list, but it may be the most interesting one ever found.
According to the analysis, this rock formed somewhere between 4 and 4.1 billion years ago, about 12.4 miles beneath the Earth's crust. Researchers knew it came from the Earth based on the amount of various minerals like quartz and feldspar, which are common on Earth but rare on the Moon. They could tell how deep it was based on a molecular analysis of the rock, which can tell the researchers what temperature the rock was at when it formed.
So the moon is about 4.5b years old. The rock is 4.1b years old. Surely by that stage the earth had re-solidified enough after the moon forming impact that an impact large enough to blow stuff into space would be noticeable as far as deformation. Any ideas where/when this impact actually happened?
I occasionally find rocks from Earth. Not sure how old they are.
What's still missing from my collection is a piece of rock from the moon.
I was gonna bash Slashdot for linking to popular mechanics (I didn't know they were still a thing?). But after reading the abstract underlying the article, I was glad to have the "in English please" version.
Don't show it to Bill Clinton... He is probably still unhappy he was tricked into saying we had found a planet Mars rock on planet Earth back in the 1990s.
Hey, wait give it to Donald Trump!!!
Keith Richards?
Have gnu, will travel.
So this makes it the first rock to do a round trip between the earth and the moon.
Someone please explain how an object gets in a circular orbit of another object it was once part of from one impact event. It's impossible. So we're meant to believe that something hit the Earth so hard (how big was this pre impact Earth BTW? Must have been fucking huge) and blew off a moon sized chunk which went flying out to a position on it's current orbit and then got hit by a second impact that put it into a beautiful circular orbit, where its rotation period just happens to match its revolution period, praise the Gods!!
Or alternatively, a big swirl of shit revolving around itself eventually formed two big swirls of shit and then came together to form the Earth and the Moon.
People believe the strangest things.
Did your secret sources tell you this too?
Keith Richards!
So the moon was created from earth... where is the life? Surely life would have enough time to evolve or be present if it came from earth. Why the contrast in life forms... abundant vs. nothing!