[ExI] 67p rosetta d/h

[Dan]

I heard that too, which is why I'd side with Tomasz here. Of course, it would be interesting if two results from the same comet varied, meaning there's likely some separation process going on.

Still, I don't have a dog in this race, so it's not like my pet theory of solar system or Earth formation is on the line. :)

Regards,

Dan

> On Dec 10, 2014, at 8:06 AM, BillK <pharos at gmail.com> wrote:
> 
>> On Wed, Dec 10, 2014 at 5:49 AM, spike  wrote:
>> <snip>
>> So, tomorrow we get a clue for where the Earth's water came from.  If 67P
>> has a D/H ratio that matches Earth, well now isn't that interesting.  If it
>> matches Mars, isn't that puzzling.  If it matches the Kuiper belt objects,
>> now what do we think?
>> 
>> Any guesses before the number comes out?  I think it will match Earth
>> because I have long since bought into the argument that our water came from
>> comets.
> 
> 
> They already announced preliminary results last month.
> 
> <http://news.sciencemag.org/europe/2014/11/doomed-comet-lander-delivered-harvest-science>
> Quote:
> And ROSINA, a Rosetta instrument that uses spectrometers to measure
> gas abundances, has obtained a highly sought after result: the
> so-called deuterium-to-hydrogen ratio of water in the comet's thin
> atmosphere, or coma. The measured value for 67P is much higher than
> the ratio in Earth's oceans and higher than in other comets, says
> ROSINA principal investigator Kathrin Altwegg, of the University of
> Bern. Three years ago, the comet Hartley-2 was found to have a D-to-H
> ratio near that of Earth's oceans--sparking interest in the notion that
> comet impacts delivered much of Earth's water. Altwegg says the result
> for 67P could make asteroids the primary suspect again.
> --------
> 
> BillK
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20141210/e8131a7f/attachment.html>