Water on Mars

[Monkey Boy]

Just curious as to what the thoughts are around here about the recent announcement by the MER team of the likelihood that water once existed on Mars. From what I've read, the key points of evidence are:

- the presence of large amounts of salts in the rocks

- the presence of "vugs" which are formed when salts crystallize and are later dissolved away

- the particular forms of layers observed in the rocks

Is the (tentative) conclusion that water once existed in quantity on Mars a valid result of the scientific method? If so, how is this conclusion any different from our conclusions about the age of the earth and biological evolution?

[geochron]

Just curious as to what the thoughts are around here about the recent announcement by the MER team of the likelihood that water once existed on Mars. From what I've read, the key points of evidence are:

- the presence of large amounts of salts in the rocks

I think the identification of jarosite, which has water of hydration, in the Mossbauer spectrum was particularly compelling. One rock sample seems to be as much as 40% sulphate salts. I'm not a real geologist, but producing this without water strikes me as difficult. Taken with other rock areas there is what looks like an evaporite sequence (we are told)

- the presence of "vugs" which are formed when salts crystallize and are later dissolved away

And the identification of the mysterious round objects as concretions - it seems clear they grew in situ.

- the particular forms of layers observed in the rocks

This was described as tentative. There seemed to be evidence of cross bedding but whether it is real and, if real, whether evidence of water or wind processes might be resolved when the rover approaches and analyses the site where they think they can see it.

Is the (tentative) conclusion that water once existed in quantity on Mars a valid result of the scientific method? If so, how is this conclusion any different from our conclusions about the age of the earth and biological evolution?

It's less certain

[Monkey Boy]

I was hoping to get more comments from the YE crowd. I would think that to a YE'r, the whole idea of sending a spacecraft to Mars to look for signs that water flowed freely millions of years ago is rather pointless.

[Socratism]

I was hoping to get more comments from the YE crowd. I would think that to a YE'r, the whole idea of sending a spacecraft to Mars to look for signs that water flowed freely millions of years ago is rather pointless.

What is pointless is the hype that implies that if water is found there then life must be there also.

"Take one part of water, add 99 parts of wishful thinking and presto, life appears."

BTW if water was once flowing freely on Mars, and that could well be the case, then it follows that something dramatic must have happened to result in the current condition.

Oh, I forgot about that magic elixir that can make anything happen.

[Monkey Boy]

What is pointless is the hype that implies that if water is found there then life must be there also.

The presence of water definitely makes the presence of life a much more realistic possibility scientifically speaking, but I don't recall anyone claiming that life *must* have existed there.

BTW if water was once flowing freely on Mars, and that could well be the case, then it follows that something dramatic must have happened to result in the current condition.

And you know this how?

Oh, I forgot about that magic elixir that can make anything happen.

That's an ironic statement coming from a YEC.

[Gilgaron]

BTW if water was once flowing freely on Mars, and that could well be the case, then it follows that something dramatic must have happened to result in the current condition.

I haven't read much on Mars's water since I was a kid, so this may no longer be the current theory: Mars has a weaker gravitational field, and also gets bombarded more often by heavy asteroids, aerosoling more water. Water aerosol is slowly lost by Mars and Earth from the upper atmosphere into space. Mars's conditions would have caused it too lose more water at a faster pace, and it started with less to begin with.

Now, I read that sometime in middle school or so, so it may not be accurate based upon current data, but I don't think anyone postulates that a single event stripped Mars of water.

[learning]

Here's a neat site I just came across that shows what may be fossils on mars. Do we have any 'fossil specialists' here and what do you think of this?
http://aix1.uottawa.ca/~weinberg/mars/

[Kulindrichnus]

Now, I read that sometime in middle school or so, so it may not be accurate based upon current data, but I don't think anyone postulates that a single event stripped Mars of water.

It's only a matter of time before Tyler gets round to it.