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The Curtmudgeon
2002-Jan-10, 06:57 PM
Article in the Times on-line today (10 Jan):

Panspermia again (http://www.thetimes.co.uk/article/0,,2-2002016079,00.html)

My basic problem with this argument is that showing something could have happened is not the same as showing either that it did happen or that it was likely to have happened. Other comments?

The (didn't ride in on no meteorite) Curtmudgeon

<font size=-1>[ This Message was edited by: The Curtmudgeon on 2002-01-10 13:57 ]</font>

ToSeek
2002-Jan-10, 07:13 PM
Yep, "plausible" is only one step on the way to "correct."

Wiley
2002-Jan-10, 11:19 PM
Considering that bacteria has been found every where we have looked on this planet, I would be surprised if bacteria could not survive in space. Some types of bacteria form a bio-film covering that makes the colony almost immune to any environmental factors.

"(deleted expletive) and the meteorite you rode in on!"

<font size=-1>[ This Message was edited by: Wiley on 2002-01-10 18:19 ]</font>

DStahl
2002-Jan-11, 05:56 AM
"...protected by particles of clay and red sandstone..."? I thought sandstone was a sedimentary rock associated with water- or wind-laid sediments. Clay I'm a little less clear on, but I thought terrestrial clay was a product of water weathering also.

Well, the geologic niceties are probably not crucial to the problem, and I may be getting my earth science wrong. Nice article, thanks!

--Don

ToSeek
2002-Jan-11, 01:38 PM
On 2002-01-11 00:56, DStahl wrote:
"...protected by particles of clay and red sandstone..."? I thought sandstone was a sedimentary rock associated with water- or wind-laid sediments. Clay I'm a little less clear on, but I thought terrestrial clay was a product of water weathering also.


This article (http://www.cosmiverse.com/science01110204.html) has more information and clarifies that the researchers were trying to simulate Martian soil, not meteoroids.

David Hall
2002-Jan-11, 01:49 PM
It looks like clay is pretty interesting stuff. I just found a link that gives a good run-down on it's composition and behaviour. I suppose it doesn't have to be sedementary in nature, but it seems very unlikely to me that other natural forces could create such a substance.

http://www.gi.alaska.edu/ScienceForum/ASF5/515.html

David Hall
2002-Jan-11, 01:59 PM
This article specifically states:

Researchers showed that spores could stay alive when exposed to ultraviolet (UV) radiation from the Sun if they were protected by particles of clay and red sandstone commonly found in meteorites.

It makes it sound like sandstone is a common substance in space, doesn't it? I suppose they might be referring to Martian meteorites only, which I suppose might have traces of sedementary rock in them. Very poor wording throughout this article.

And another thing, this article says this is the first proof of bacteria being able to survive in space. Didn't they find some still-living bacteria on the parts they brought back from the Surveyor probe on the Moon?

Jim
2002-Jan-11, 02:16 PM
It looks like clay is pretty interesting stuff.


The most widely held non-creationist mechanism for the beginnings of life has it starting out in tidal pools. Another theory says it started in clay.

Recently it has been shown that it is possible to form RNA from monomers on the surfaces of clays, which can catalyze, or chemically assist, the polymerization reaction. Experiments done in test tubes (in vitro) have shown that RNA with one type of catalytic activity can evolve to an RNA with different catalytic properties. These two sets of experiments suggest that it may be possible to demonstrate how clay minerals could have permitted the formation of complex RNA molecules that are capable of evolving in form.

http://www.sciam.com/askexpert/biology/biology15.html



Didn't they find some still-living bacteria on the parts they brought back from the Surveyor probe on the Moon?


Good memory!

In November, 1969, the Surveyor 3 spacecraft's microorganisms were recovered from inside its camera that was brought back to Earth under sterile conditions by the Apollo 12 crew.

http://science.nasa.gov/newhome/headlines/ast01sep98_1.htm


<font size=-1>[ This Message was edited by: Jim on 2002-01-11 09:17 ]</font>

Bob S.
2002-Jan-11, 03:35 PM
The fact that bacteria spores could survive a wide variety of hostile environments including the vacuum of space is old news. The big question is, how would it get into space to begin with?

Could even a bacteria spore survive the intense heat generated by an asteroid impact that would blast it into escape velocity?

Or would the proponents of Panspermia suggest that abiogenesis would occur on the surfaces of cold airless comets that are somehow more hospitible to early life than the warm wet tidal pools or deep sea thermal vents of Earth? :-|

Chip
2002-Jan-11, 06:02 PM
On 2002-01-11 10:35, Bob S. wrote:
"...Could even a bacteria spore survive the intense heat generated by an asteroid impact that would blast it into escape velocity?"


=============================================

Simply put, one idea is that some bacteria deep inside rocks located at just the right spot on the periphery of a large impact, might be protected from heat, achieve escape velocity, and survive a space voyage from Mars to Earth.

The rocks would have to be large enough to again survive additional intense heat, this time from entering Earth's atmosphere.

Pretty slim odds, but if a lot of bacteria inhabited rocks were blown out, only a few would have to make it to Earth.

If this were ever proven, we could possibly call ourselves "Martians colonists." /phpBB/images/smiles/icon_wink.gif

Russ
2002-Jan-11, 06:24 PM
On 2002-01-11 13:02, Chip wrote:
If this were ever proven, we could possibly call ourselves "Martians colonists." /phpBB/images/smiles/icon_wink.gif


If this were ever proven, we must revolt and throw off the mantal of opression. To grok freedom in fullness. I will not discorporate until waiting is. /phpBB/images/smiles/icon_wink.gif

DStahl
2002-Jan-11, 08:12 PM
Oh, ok (way back up the thread) I wasn't clear that the research involved simulating Martian-rock type meteoroids.

David--Yeah, clay is pretty interesting stuff. I wonder, is it possible that some combination of erosion by micrometeorite impacts, the action of comsic rays, and radiation on some asteroids might give rise to substances that are similarly complex and interesting? After all, we get to dig around all over the Earth and we have a whole terminology devoted to soil types, but the only soil samples we have for other bodies in the Solar System are a few grabs from the Moon.

Who knows what cool dirt lurks 2 meters down on a carbonaceous chondrite-type body? Yoicks!

--Don

David Hall
2002-Jan-11, 10:49 PM
On 2002-01-11 15:12, DStahl wrote:

David--Yeah, clay is pretty interesting stuff. I wonder, is it possible that some combination of erosion by micrometeorite impacts, the action of comsic rays, and radiation on some asteroids might give rise to substances that are similarly complex and interesting? --Don


Yes, I was thinking the same thing just a little. That's why I said I thought it was possible. However, I still think it isn't very likely. Maybe something vaguely clay-like, but true clay? Hmm.

Chip
2002-Jan-11, 11:32 PM
On 2002-01-11 17:49, David Hall wrote:
Yes, I was thinking the same thing just a little. That's why I said I thought it was possible. However, I still think it isn't very likely. Maybe something vaguely clay-like, but true clay? Hmm.


Clay eh? Of course Wallace and Gromit discovered cheese under the Moon's top-soil. It's all documented in their film titled:
A Grand Day Out (http://www.aardman.com/wallaceandgromit/films/agranddayout/index.shtml). /phpBB/images/smiles/icon_smile.gif Have a Nice Weekend!

DStahl
2002-Jan-12, 04:00 AM
Ooooh nooooo! It's a conspiracy! Wallace & Grommit = claymation! Clay is everywhere!

Seriously, though, I was thinking in a very fuzzy speculative way that maybe some sort of material which is physically not like clay at all but has some of its complexity may form on astroids or airless planets--say some sort of carbon (graphite?) microplates in a matrix of pulverized silica, or something. Maybe it would have properties we that would be unexpected and rather intriguing. Oh well, nothing for it, we just gotta go up there and start looking.

--Don

<font size=-1>[ This Message was edited by: DStahl on 2002-01-11 23:01 ]</font>

Chip
2002-Jan-12, 04:37 AM
On 2002-01-11 23:00, DStahl wrote:
Ooooh nooooo! It's a conspiracy! Wallace & Grommit = claymation! Clay is everywhere!

Seriously, though, I was thinking in a very fuzzy speculative way that maybe some sort of material which is physically not like clay at all but has some of its complexity may form on astroids or airless planets--say some sort of carbon (graphite?) microplates in a matrix of pulverized silica, or something. Maybe it would have properties we that would be unexpected and rather intriguing. Oh well, nothing for it, we just gotta go up there and start looking.
--Don


Come to think of it, I sort of remember a painting by that terrific old time spaceman Chesley Bonestell. A typical, speculative yet meticulous picture by him of a comet as seen way way out in the Oort cloud and not glowing from escaping gas. It looked delicate, like an irregular very sloppy loose snowball.

Also, with regards to material that is clay-like, when the NEAR mission "neared" its end, and the probe slid onto the surface, did not the close up soil look strange and not really the same as lunar soil? Also, I seem to remember that earlier the NEAR camera spotted strange pool-like dusty areas, perhaps in craters -- and it was speculated that maybe the "soil" there was behaving not unlike a liquid (though very cold and dry) and was perhaps even suspended above the ground. Anybody remember that?

ToSeek
2002-Jan-14, 02:27 PM
On 2002-01-11 23:37, Chip wrote:
Also, I seem to remember that earlier the NEAR camera spotted strange pool-like dusty areas, perhaps in craters -- and it was speculated that maybe the "soil" there was behaving not unlike a liquid (though very cold and dry) and was perhaps even suspended above the ground. Anybody remember that?


Yes (article from Nature) (http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v413/n6854/abs/413396a0_fs.html)

alfricnow
2004-Dec-29, 02:43 AM
if I remember one of the last astronautauts to go to the moon brought back parts of the lander or rover or something from an earlier mission and the bacteria from a sneeze was found in the camera and had survived its time on the moon.