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Study Questions Scientific Dating Method Used For Lunar Impacts (wisc.edu)
schwit1 writes: A new study has raised questions about the methods scientists have used to date the late heavy bombardment in the early solar system. According to the University of Wisconsin-Madison: "A study of zircons from a gigantic meteorite impact in South Africa, now online in the journal Geology, casts doubt on the methods used to date lunar impacts. The critical problem, says lead author Aaron Cavosie, a visiting professor of geoscience and member of the NASA Astrobiology Institute at the University of Wisconsin-Madison, is the fact that lunar zircons are ex situ, meaning removed from the rock in which they formed, which deprives geoscientists of corroborating evidence of impact. 'While zircon is one of the best isotopic clocks for dating many geological processes,' Cavosie says, 'our results show that it is very challenging to use ex situ zircon to date a large impact of known age.'" The problem is that the removal of the zircon from lunar rocks changes the data enough to make the dating unreliable. The method might work on Earth, but the dating done on Apollo samples can be questioned. This means that much of the supposed history of the solar system, centered on what planetary scientists call the late heavy bombardment, a period 4 billion years ago when the planets were being hit by innumerable impacts as they cleared the solar system of its dusty debris disk, might not have happened as dated from lunar samples. If so, our understanding of when that bombardment ended and life began to form on Earth might be considerably incorrect.
Did anyone else think this was going to help them pick up chicks? ;-)
I'd like to hear more about this Scientific Dating Method.
I got to "lunar impacts" before I realized it wasn't going to be an article about matchmaking algorithms at dating websites. And I spent at least a fraction of a second considering that "lunar impacts" is a strange name for a dating website.
I guess I need to brush up on my Latin...
Two of my imaginary friends reproduced once
>evidence of early bombardment on Earth
>assuming that this might not have happened on the Moon
That's a pretty big assumption, because it assumes that the Earth is somehow special in "attracting" (outside of gravity, but we're not talking about that, we're just talking about "targeting") bombardment and the moon is not, while both occupy a similar orbits around the Sun.
I don't buy this doubt. It fails the laugh test.
--
BMO
Wow. Whoda thunk.
It may be wrong doesn't mean it isn't right.
I tried Prof Nash's method from the movie "A Beautiful Mind", and I got a glass of beer thrown in my face.
I thought it was obvious, dinner and a movie. Did this need a study?
“He’s not deformed, he’s just drunk!”
There's no such claim in the article or summary. The moon rocks don't have the full surroundings available to make sure it wasn't just existing zircons knocked about by an impact rather than formed in that impact. Evidence from the moon is being used to time the late heavy bombardment. So we're no longer sure the evidence we found on the moon is good enough to narrow down the timing as much as we thought.
"Candy's dandy, but liquor's quicker" - Ogden Nash
....I'll settle for any dating method.
Don't tell the man made global warming crowd...
awesome, free beer, just open mouth!
thanks!
I've met a fair number of Late Heavy Bombardments, but can't say it occurred to me to date them. Have they tried rolling it in flour and going for the wet spot?
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
Well, I thought it was obvious. First, go to your nearest poultry farm...
Escher was the first MC and Giger invented the HR department.
Criminal nonsense! The models "prove" what happened. We have a graph shaped like a hockey stick that shows the heavy bombardment started 4 BYA. It's proven science, 97.36% of scientists agree. These cheese-heads are true deniers! If there was more money and power involved in this research I'm sure they would be publicly disgraced and banned from further grant money.
Newton's Laws of Motion were settled science until they weren't when Einstein came along. That doesn't mean they were wrong, just that they have more limited applicability than originally thought.
Yes, yes, as we all know science is wrong, and the earth was made approximately 5000 years ago. And the earth is flat.
Newton's Laws of Motion were useful approximations but clearly wrong. I'm sure Einstein won't be the last word on it either. Science shouldn't be about right and wrong, but when it's politicized (power and money involved) it tends to become a black/white, right/wrong, settled/denier argument.
I want a scientific dating method for impacts on Uranus!
Don't tell the man made global warming crowd...
Actually, don't tell the deniers.
The idea that scientists are willing to say - "We might be wrong here" is the polar opposte of the denier's claims.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
it is pay first, idiot
Newton's Laws of Motion were useful approximations but clearly wrong.
Clearly wrong to who? You? Clearly wrong when? Certainly not until relatively (pun intended) recently.
The fact is, at speeds and scales perceptible to the human animal, Newton's Laws of Motion are clearly right. For you to so cavalierly dismiss Newton, you only put your own ignorance on display. Or maybe your problem isn't simple ignorance that could be cured by mere education...maybe you've got, like, an Axis II problem. Yeah, I bet that's what's going on here.
Cheers!
"The fact is, at speeds and scales perceptible to the human animal, Newton's Laws of Motion are clearly right."
No. They aren't. Classical Physics is not about bringing the proper numbers but bringing the proper arguments -that, in turn, lead to mathematical expressions that can be tested against experiments. That's why Ptolemaic astronomists were wrong while Copernicus was right despite of the results of the formers being more accurate than those of the latter (it was not till Kepler proposed using ellipses instead of circles that Copernicus' astronomy would render better results).
In Newton's case, the numbers are pretty close, but laws missed the target by a far stretch (the fact that the numbers were so close is what made people think for the laws to be right for so long): there's no such a thing as an absolute reference framework and its nonexistence offers a completely different vision of our universe.
"For you to so cavalierly dismiss Newton"
This is neither football nor politics so it's not about which team wins the match. Newton was an utter genius and no amount or further research will ever deny that. It's only he was wrong as much as was Ptolemy, but they both failed in a most honorable manner that paved our way to further knowledge.
Did anyone else think this was going to help them pick up chicks? ;-)
No. That's in the "rod logic" article.
It must have been something you assimilated. . . .
Aristarchus of Samos was more right than Ptolemy. But everyone was so sure that planets must travel in circles, and that the earth must be the center of the solar system. Epicycle theory flourished because of human projection: I'm not moving, the sun is moving!
There are visible signs of life on Earth that are 3.7 billion years old, so it's at least that old..
"One of these days Alice—pow! Straight to the Moon!"