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ToSeek
2004-Sep-22, 09:26 PM
Nature: A picture of young Mars (http://www.nature.com/news/2004/040920/full/040920-7.html)


What would Mars's oceans have looked like 4 billion years ago? Scientists have worked out the answer, and found a planet with a climate ideally suited to life.

National Geographic: Mars Had Ocean, Controversial New Theory Says (http://news.nationalgeographic.com/news/2004/09/0922_040922_mars_ocean.html)


"We have evidence of huge amounts of water, and a segment of the scientific community has been convinced that Mars had oceans since at least the 1980s," said Victor Baker, a planetary scientist and geoscientist at the University of Arizona in Tucson.

But other scientists disagree. "One reason why has been the failure to detect significant deposits of carbonates that are associated with the presence of an ocean," Baker said.

Space.com: Mars, Once Warm and Wet, Left Some Clues (http://space.com/scienceastronomy/mars_fizz_040922.html)


A new theory about ancient Mars puts some fizz back in the idea that the red planet was once warm, wet and potentially habitable.

01101001
2004-Sep-22, 09:58 PM
National Geographic:
"We have evidence of huge amounts of water, and a segment of the scientific community has been convinced that Mars had oceans since at least the 1980s," said Victor Baker, a planetary scientist and geoscientist at the University of Arizona in Tucson.
Heh. Come on. If Mars had oceans since the '80s how did they disappear so fast?

I dunno. That sentence just tickled me. I think it needs a rewrite:

[...] a segment of the scientific community has been convinced, since at least the 1980s, that Mars had oceans.

But, it is a quote, so what does a good editor have to do to nail down the actual meaning?

George
2004-Sep-22, 10:57 PM
Interesting. The Earth has vents which filter the salts, etc. Then there is plate tectonics which, likely, help out, too.

Wasn't it hydrogen sulfides, methane, CO2 and water which Miller used to form amino acids, etc. by adding electrical sparks?

Which is more likely to make it to Earth due to a major impact....material expelled from a water impact or from a ground impact? Wouldn't the watery material get a push from the tremendous water-to-gas expansion increasing it's advantage?

Is it believed that Mars did have a head start on life before Earth did? If so, panspermia may have just gained a notch. (Not that I know much about this...I even skipped biology) :)

Cugel
2004-Sep-22, 11:20 PM
The gases they (Urey and Miller) used were methane (CH4), ammonia (NH3), hydrogen (H2), and water (H2O). At that time this was considered to be the composition of the primitive Earth atmosphere. However, if you run the experiment with a CO2 and Argon mixture nothing happens. So, which planet (or moon) in the early Solar system was blessed with a Urey/Miller atmosphere? Probably not the Earth. Not Mars. Very likely not Venus. So where did the first life evolve? Or are we missing something?

Just a link: http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/miller.html

Cylinder
2004-Sep-23, 01:16 AM
If Mars had oceans since the '80s how did they disappear so fast?

Parachute pants, the Rubik's Cube, Martian oceans...those were the good ole' days. 8) That sentence gave me pause as well.

Bounced Check
2004-Sep-23, 03:00 AM
Re-read the sentence - they are saying that there are scientists who believed that the oceans exsisted in the ancient past and they have believed this since the 80's, NOT that there were oceans up untill the 1980's.

jt-3d
2004-Sep-23, 03:24 AM
So I guess you didn't bother to read the second post in this thread either.

ToSeek
2004-Sep-23, 03:27 AM
Re-read the sentence - they are saying that there are scientists who believed that the oceans exsisted in the ancient past and they have believed this since the 80's, NOT that there were oceans up untill the 1980's.

We understand that, but the sentence could have been phrased better.

Bounced Check
2004-Sep-23, 11:51 AM
I'm sorry - did I do something wrong? If I did I'm sorry. I'll try to keep myself out of things. Untill I started posting here I've never used the internet other than emailing family and friends, so it's all new to me really.

Doodler
2004-Sep-23, 01:48 PM
I'm sorry - did I do something wrong? If I did I'm sorry. I'll try to keep myself out of things. Untill I started posting here I've never used the internet other than emailing family and friends, so it's all new to me really.

Not at all, except miss a mild joke at the expense of someone's bad grammar.

:D

George
2004-Sep-23, 08:56 PM
The gases they (Urey and Miller) used were methane (CH4), ammonia (NH3), hydrogen (H2), and water (H2O). At that time this was considered to be the composition of the primitive Earth atmosphere.
Thanks. I've been listening to Bill Bryson's cd's and he mentions H2S. His cd's have been erroneous on many occasions. :-?

I did find that about 2% of the carbon in their experiment went to form amino acids.

My other questions still stands unanswered....

Could a large impact on Martian water eject material easier than on Martian ground?

Cylinder
2004-Sep-24, 02:06 AM
I'm sorry - did I do something wrong? If I did I'm sorry. I'll try to keep myself out of things. Untill I started posting here I've never used the internet other than emailing family and friends, so it's all new to me really.

I wouldn't sweat it. The fact that you questioned your own statement before initiating a rant is a pretty good indicator that you'll fit in just fine.

Bounced Check
2004-Sep-24, 12:02 PM
There is one thing that I'm 100% sure of - that I can never be 100% sure of anything.

Doodler
2004-Sep-24, 03:03 PM
There is one thing that I'm 100% sure of - that I can never be 100% sure of anything.

The worst mistake you can make is to be afraid to make mistakes.

Cugel
2004-Sep-24, 05:23 PM
Could a large impact on Martian water eject material easier than on Martian ground?

Well, I guess a big impact will evaporate rock just as easy as water. So I don't think there is any difference at all. The effects for Mars itself would be greatly different of course. It is probably this sort of events that stripped Mars of its ancient oceans. (If they ever existed...)

George
2004-Sep-27, 02:55 PM
Could a large impact on Martian water eject material easier than on Martian ground?

Well, I guess a big impact will evaporate rock just as easy as water. So I don't think there is any difference at all.
I am unsure about this. Water expands about 1700x it's volume at 1 atm. ( I don't know how much rock expands).

I am curious if more of a vertical thrust might occur in a water impact. #-o