English Researchers Find Extra-Terrestrial Water

Lister of Smeg writes: "Some researchers found water on a meteorite that is about 570 million years older than the oldest terrestrial rocks. The implications are that water isn't as rare as we thought, conditions for life may have existed elsewhere in the solar system before Earth, and from the article ... 'There is this old idea that life on Earth may have been seeded from somewhere else.'"

Comments

Re:Fun with geologic numbers....

[orpheus]

Iodine has a relatively short half-life of 15.6 Myr, and is generally considered useless for measurement on this time scale (i.e. almost 300x the half-life) After 300 half-lives, you'd expect 1 part in 2x10^90! That's one single atom left from 1.77 x 10^65 kg of I-129 - more than the mass of the universe, much less the mass of the I-29 in the universe (and, I'm willing to wager, more than the mass of the meteorite!)

The WashU Laboratory of Space Sciences has a page on isotope age determination in meteors, geologic formations and other ancient inorganic structures. Here's what they say on this very point:

Iodine-129 is now extinct in nature. Its short half-life, 15.6 million years, means that Iodine-129 has long since decayed away in a solar system that is 4.6 billion years old.

Furthermore, any radioisotope age determination is based on two things: a) a knowledge of the relative prevalence of the isotope; and b) the half-life. [If the original prevalence is not known, you can sometimes make estimates from decay products of multiple unrelated isotopes]

According to the 'standard' half-life, I-129 is not a useful isotope, but to make things worse, this sample was irradiated by the high-energy space environment for a very long time (I'm assuming millions or billions of years). Irradiation can cause accelerated decay, changing the effective half-life.

Bottom line: unknown original prevalence (somewhere in space, at some unknown time), unknown effective half-life, due to unknown but significant irradiation history, and an unsuitable isotope. Ugh. This is Scientology!

You'd get a better estimate by flipping coins for binary bits. Wait! Maybe they did! How else did they get that number at all?

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Brought to you by the guy who outed Katz as a Scientologist!

Re:Hogwash

[cje]

Only a higher being could have given us a rose, a bald eagle, a rainbow, etc.

Yes, but that would then mean that the "higher being" also gave us Pauly Shore. This is direct evidence against the existence of a god that is both omnipotent, omniscient, and all-loving.

Water plentiful?

[hypergeek]

There's probably some race of silicon-based extraterrestrials out there, looking at all these planets, thinking, "We must be the only life in the Universe... ours is the only planet we've found without an abundance of that horrible, poisonous, life-quenching water!"