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4.4 billion-year-old crystal is oldest confirmed piece of Earth

cnn.com

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Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#31

Post by evincarofautumn »

teddyh wrote: post #20
yeukhon wrote: post #6

I just search a bit about Jack Hills. http://en.wikipedia.org/wiki/Jack_Hills The last modified was last December. The actual paper http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo20... was received last July but published on Fed 23, 2014. So it took a while to confirm and accept by the reviewers using the new technique. And Jack Hills seems to have caught a lot of attention as early as 2006. http://earthob…

The almost incomprehensible age of the Earth was famously summarized thus: “The reſult, therefore, of our preſent enquiry is, that we find no veſtige of a beginning,–no proſpect of an end.” — Theory of the Earth , James Hutton, 1788

On a ſide note, we ſhould bring back the long S.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#32

Post by lutorm »

evilduck wrote: post #30
mathattack wrote: post #19

Isn't everything on the earth this old? The dirt in our backyard has been around for 4.4 billion years too. Or is it that this crystal hasn't been changed in that long?

The dirt in your back yard hasn't been around for 4.4b years. Topsoil (decayed organic material and newly eroded rocks mostly) is usually pretty 'young' on geological timescales.

Not in that form, but the vast majority of the matter certainly has been part of the Earth for that long.

By the same definition, I'm not 40 years old either, because practically no part of me is left since I was born.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#33

Post by chongli »

mathattack wrote: post #19

Isn't everything on the earth this old? The dirt in our backyard has been around for 4.4 billion years too. Or is it that this crystal hasn't been changed in that long?

When you put it that way, everything in the universe is the same age.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#34

Post by joe_inferno »

evincarofautumn wrote: post #31
teddyh wrote: post #20

Earlier quoted context omitted.

The almost incomprehensible age of the Earth was famously summarized thus: “The reſult, therefore, of our preſent enquiry is, that we find no veſtige of a beginning,–no proſpect of an end.” — Theory of the Earth , James Hutton, 1788

On a ſide note, we ſhould bring back the long S.

yes, that was annoying

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#35

Post by teddyh »

evincarofautumn wrote: post #31
teddyh wrote: post #20

Earlier quoted context omitted.

The almost incomprehensible age of the Earth was famously summarized thus: “The reſult, therefore, of our preſent enquiry is, that we find no veſtige of a beginning,–no proſpect of an end.” — Theory of the Earth , James Hutton, 1788

On a ſide note, we ſhould bring back the long S.

Yea, and alſo þe þorn! More seriously; it’s a text from 1788 – I’d think I was allowed to keep its spelling and not translate or transliterate when I’m actually quoting it verbatim.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#36

Post by mathattack »

chongli wrote: post #33
mathattack wrote: post #19

Isn't everything on the earth this old? The dirt in our backyard has been around for 4.4 billion years too. Or is it that this crystal hasn't been changed in that long?

When you put it that way, everything in the universe is the same age.

That's where I was going. What do they mean by age?

Although one could argue that the speed things travel through the universe alters their age, but from when the Earth materialized, it shouldn't change much from particle to particle.

If you're arguing for "oldest living thing" I do get it.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#37

Post by mathattack »

lutorm wrote: post #32
evilduck wrote: post #30

Earlier quoted context omitted.

The dirt in your back yard hasn't been around for 4.4b years. Topsoil (decayed organic material and newly eroded rocks mostly) is usually pretty 'young' on geological timescales.

Not in that form , but the vast majority of the matter certainly has been part of the Earth for that long. By the same definition, I'm not 40 years old either, because practically no part of me is left since I was born.

Right, but at least we can say you're a relatively old "living" creature where age is a more relevant number. (I'm getting up there in "relatively old" years too.)

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#38

Post by jofer »

s0rce wrote: post #11
yeukhon wrote: post #6

I just search a bit about Jack Hills. http://en.wikipedia.org/wiki/Jack_Hills The last modified was last December. The actual paper http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo20... was received last July but published on Fed 23, 2014. So it took a while to confirm and accept by the reviewers using the new technique. And Jack Hills seems to have caught a lot of attention as early as 2006. http://earthob…

Correct, this paper demonstrated that the Pb doesn't move around too far that it would invalidate the previous measurements. This was done using atom probe tomography. Source: I know John and also do atom probe work. Also, It was accepted at the end of last year and took a bit to publish, not unusual.

On a side note, JV is one of the most universally respected scientists I've seen. (JV --> John Valley, for various reasons everyone at Wisconsin calls him "JV".)

He's an absolutely huge name in the field, and actually treats his students/postdocs very well. He expects a lot in return, but he really does look out for people.

Re: 4.4 billion-year-old crystal is oldest confirmed piece of Earth

#39

Post by evincarofautumn »

teddyh wrote: post #35
evincarofautumn wrote: post #31

Earlier quoted context omitted.

On a ſide note, we ſhould bring back the long S.

Yea, and alſo þe þorn! More seriously; it’s a text from 1788 – I’d think I was allowed to keep its spelling and not translate or transliterate when I’m actually quoting it verbatim.

It’s fine, I understood what you were up to. In earnest, though, I’d rather see thorn and eth come back than long S.
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