Instant Earth, Just Add Dust Particles

EvilSuggestions writes "Apparently, the estimate for how long it took for the Earth to form just got chopped in half. Now just a paltry 30 million years (which, IIRC, is less than one day on Carl Sagan's 1 year = the life of the universe calendar). So, adjust your terraforming plans appropriately. The good folks over at Science News have been following the gory details behind this conclusion."

Comments

Re:accuracy?

[Quelain]

This might be what you're looking for:

http://www.talkorigins.org/faqs/isochron-dating.ht ml

Re:Mega-crap

[offpath3]

Being a resident of Hawaii, I really must throw in my two cents here. A few years back some austrailian wallabes go loose in the Koolaus (mountain range) in Hawaii. Drastic adaptive changes were seen within only several generations of wallabes and this is one of the main pieces of evidence to support the "punctuated equilibrium" theory of evolution. Don't have a link on me, but I'm sure you can google it yourself. Just because you don't know of any evidence doesn't mean it doesn't exist.

If I remember my highschool bio correctly, there was also a moth that evolved a darker coloring after a nearby coal plant blackened the forest the moth lived in.

Re:accuracy?

[cp99]

However, how accurate are field conditions? Minerals move and change over such a large period of time, so how does one know when one has a representative ratio of (say) tungsten-182 and hafnium-182? A you pointed out, it was the sampling techniques that were flawed in the original estimate. How does one show that the techniques used in this sample (and others) are accurate?

There are several ways in which one can check the accuracy of radiodating in the field.

For recent (on the historical timescale) events, one can compare radiodates with historical dates. For example, radiodating lava from Pompay gives the same date as what can be derived from Romen records).

Another much more general method (as it doens't rely on other information), is compare radiodates of various techniques.

For example, the Meteorite named Saint Severin was radiodated with Sm-Nd, Rb-Sr and Ar-Ar dating. If one isotope was migrating, then one dates optained would be off, if all of the isotopes were migrating, then all of the dates would be off (they would migrate at different speeds).

We get the following results:

Sm-Nd 4.55 +/- 0.33

Rb-Sr 4.51 +/- 0.15

Ar-Ar 4.43 +/- 0.04, 4.38 +/- 0.04, and 4.42 +/- 0.04

However, that being said, many individual radiodates are heatly debated in the science lit., however, the accuracy of the technique as a whole is well established.