Carbonate found on Comet Tempel 1 by Deep Impact mission?
Robert Clark
Tempel I.
© 2005 by Linda Moulton Howe
http://www.earthfiles.com/news/news.cfm?ID=960&category=Science
This is important because carbonate requires liquid water to form.
This is on a controversial web site, but the detection of carbonate is
confirmed by the Deep Impact scientist here:
Workshop on Dust in Planetary Systems 2005
Deep Impact and Comet 9P/Tempel 1 : From Evolved Surface to Interior
Primeval Dust.
C. M. Lisse Johns Hopkins University Applied Physics Lab, Laurel MD
20723 (carey.*****@******.edu)
http://www.lpi.usra.edu/meetings/dust2005/pdf/4105.pdf
Bob Clark
dlzc1 D:cox T:net@nospam.com N:dlzc D:aol T:com (dlzc)
"Robert Clark" <rgrego...@yahoo.com> wrote in message
news:1124633251.1...@o13g2000cwo.googlegroups.com...
>Deep Impact Spectra: Carbonate, PAHs and Some Amino Precursors
>in Comet
>Tempel I.
>(C) 2005 by Linda Moulton Howe
>http://www.earthfiles.com/news/news.cfm?ID=960&category=Science
>
> This is important because carbonate requires liquid water to
> form.
> This is on a controversial web site, but the detection of
> carbonate is
> confirmed by the Deep Impact scientist here:
Triple point. Ice, water, and steam can coexist. The brief
presence of liquid water in an object that (normally and largely)
sublimes from solid to gas is not out of the question.
David A. Smith
rick++
Robert Clark
http://www.jpl.nasa.gov/news/news.cfm?release=2005-144
Composition of a Comet Poses a Puzzle for Scientists
By KENNETH CHANG
Published: September 7, 2005
"In the burst of light after the collision, Spitzer detected specific
colors of infrared light that indicated that Tempel 1 contained clays
and carbonates, the minerals of limestone and seashells.
"Clays and carbonates both require liquid water to form.
"How do clays and carbonates form in frozen comets where there isn't
liquid water?" said Carey M. Lisse, a research scientist at the Applied
Physics Laboratory at Johns Hopkins University who is presenting the
Spitzer data today at a meeting of the Division for Planetary Sciences
in Cambridge, England. "Nobody expected this."
http://www.nytimes.com/2005/09/07/science/07comet.html?oref=login
[may require free registration]
I'm surprised Lisse would say nobody expected the aqueous minerals to
be seen. It is a well-known theory among comet researchers that
radioactive heating may have allowed liquid water to form in comets
early on in the Solar Systems history.
This theory was probably only controversial because it raises the
possibility of life in comets, especially given the large abundance of
organics, also confirmed by Deep Impact, in comets.
Bob Clark
Robert Clark
On the space oriented bbs uplink.space.com someone mentioned the
detections of olivine in Tempel I and previously in other comets raise
the possibility of more heating in comets than would be expected for
objects formed far from the Sun. This would also be consistent with the
theory of radiogenic heating in comets:
NASA Research Finds Green Sand Crystals Are in Comet Tempel 1.
Date Released: Thursday, September 15, 2005
http://spaceflightnow.com/news/n0007/20cometdust/
Time travel through a trail of comet dust.
NASA/GSFC NEWS RELEASE
Posted: July 20, 2000.
"We know that these dust grains change from amorphous to crystalline as
they are heated, and our laboratory research revealed that the rate at
which they change is extremely sensitive to temperature," Nuth added.
"At the very low temperatures, where water-ice and the other volatile
components of comets are frozen, the time required for amorphous
silicate dust grains to change to the crystalline olivine found in
comet Halley is many times longer than the age of the Universe."
http://spaceflightnow.com/news/n0007/20cometdust/
So there at least three separate and independent indications of
internal heating, likely radiogenic, in comets: carbonate/clay detected
in Tempel I, olivine in Tempel I and other comets, and crystalline ice
detected deep in the Kuiper belt:
Chilly Quaoar had a warmer past.
Mark Peplow
Crystalline ice suggests remote object has radioactive interior.
Published online: 8 December 2004.
http://www.nature.com/news/2004/041206/pf/041206-7_pf.html
Bob Clark