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#26 2002-06-26 10:13:59

JGM
Member
Registered: 2001-09-04
Posts: 26

Re: H20, where'd it go? - What happened to Marsian water?

I know where Byron is coming from. I live 16 degrees off the equator and summer here gets pretty sticky!
   I have no quarrel with his 280 deg.K planetary average just as long as the northern ocean doesn't freeze over. The problem which bothers me is the high albedo of ice. If you allow too much of the ocean to freeze white, you start losing a lot of insolation through reflection off the ice ... which leads to lower temperatures ... which leads to more ice .... !! A runaway refrigeration effect. As I've recently mentioned elsewhere, this effect, even here on Earth, worries me more than the possibility of global warming.
   Byron is probably right. We'll most likely have to use mirrors to artificially elevate the north polar temperature. Otherwise, as he suggests, we may have to swap cold deserts for hot deserts at the equator and over large areas of the southern hemisphere.
   Just to throw another curve-ball into the argument, I have another little problem I like to try and ignore! Mars has no overall, uniform, magnetic field. I'm no zoologist but I know that many species here on Earth rely on a strong steady magnetic field in order to function properly (or at all! ). What if far more species than we realise have to have such a field in order to live?! What if almost all Earth life gradually falters and dies without that field? Unlikely, I suppose. But it's an idea which has obviously never been tested, apart from a few humans who managed to remain functional on the Moon for a few days. On Mars, at the very least, you can forget about racing your homing pigeons ... they won't know north from south from a hole in the wall! But it could be much more serious than that. Who knows?!
   No tides, no homing pigeons ... maybe no viable life at all! Can anybody out there cheer me up??!!
                                           ???[/quote:post_uid0]

No tides, no homing pigeons ... maybe no viable life at all! Can anybody out there cheer me up??!![/quote:post_uid0]
I'll try. The thing I don't understand about the drive to terraform is why we want to make it into another Earth. To me what makes Mars attractive is its surreal differences from Earth, while still offering the possibility of providing a place where humans might be able to gain a foothold off planet.

I'm intrigued at the possibilties of radically transforming the Mars we see today, largely because it's close enough to Earthlike that to do so we could give life a chance to survive and thrive there (Earth life and any Mars life that might be still holding on). Sax Russell long ago convinced me that life makes a world a very interesting place. I don't want it to end up just like Earth, though. I'd rather we moved out into the solar system enough to be able to restore Earth's unhealthy ecosystems so we always have our original garden planet to visit and admire.

As for Mars, imagine the possibilities of how life would adapt to the unique constraints it imposes. Homing pidgeons would have to find some other way to home. A non-tidal ocean would develop its own unique ecosystems entirely new. Most of all intriguing to me is the idea that native Mars life, were it found still alive, and Earth life could eventually mix and create new hybrid life forms and life communities with characteristics that we couldn't begin to anticipate.

Feel any better?  smile

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#27 2002-07-03 22:01:46

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

Yes, JGM! I'm sure you must be right .... to borrow a phrase from "Jurassic Park", 'life finds a way'!
   Maybe I worry too much!!
                                         big_smile


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#28 2002-12-06 08:25:10

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: H20, where'd it go? - What happened to Marsian water?

*"New Theory Says Mars Never Had Oceans"...I got this from Yahoo! news just now, a.m.:

http://news.yahoo.com/fc?tmpl....oration

--Cindy


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#29 2002-12-06 14:40:03

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: H20, where'd it go? - What happened to Marsian water?

Jinx, Cnidy. wink


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#30 2002-12-06 15:15:24

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: H20, where'd it go? - What happened to Marsian water?

Jinx, Cnidy. wink[/quote:post_uid6]
*Yeah, about an hour after I posted here, I noticed you'd posted the same article in the "New Discoveries" folder [you posted it before I did].

Well, there's only one thing to do:  We'll have to link pinkie fingers and do the "bread and butter!" unjinxing thing.  smile

--Cindy


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#31 2002-12-06 19:52:44

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

All the planets and moons were subjected to intense bombardment in their early years.
    The picture they've painted of a hellish Mars was repeated all over the place, including here on Earth. There's nothing new in what they say. In fact, I don't understand why they've suddenly released all this stuff - it's a complete non-event dressed up as new research.

    Apparently they can't understand how Mars could have been warm and wet enough to produce the surface erosional features we see everywhere. So they've decided it all happened during the late heavy bombardment and stopped immediately afterwards, except for maybe a little volcanically induced melting of permafrost later on.

    This, to me, is an example of a spurious argument at its most obvious. First you accept a premise that Mars couldn't have maintained warm wet conditions. But what about all those river valleys and outflow channels? Hmmm ... let's blame it all on the heat released by impacts! Hell, we can even use this hypothesis to provide the rainfall necessary to explain the branched valley networks all over the southern highlands!!
    This way, we can have a planet permanently frozen, barren, and inhospitable (which fits in with the 'Faint Young Sun Paradox' ), and yet still account for the water features ... brilliant!

    It's a nice try but it won't work.

    The evidence for flowing water on Mars shows that there have been long periods of clement conditions over most of the planet's history. Just recently (wish I could remember where), I was reading that evidence shows there has been almost continuous water drainage from Argyre, north via Uzboi Vallis and Ares Vallis, out onto Chryse Planitia, over billions of years.
    Go back, in this thread, to my post which I made in June, about an absolutely huge lake bed discovered just south of the equator at about 180 deg. W. They've even identified the shoreline. This lake contained 5 times more water than The Great Lakes and it spilled northwards over a natural weir for who knows how many thousands of years.
    In another thread, Josh drew attention to the smoothness of the northern plains of Mars and wondered how anything but an ocean could have formed them. I agree with him. Those plains are easily the smoothest large scale surfaces in the entire solar system. Smoother even than their only rivals for smoothness, the abyssal plains of Earth's oceans!!
    There's little doubt in my mind that Mars has experienced long periods of "nice weather"! Long-lived standing bodies of water have almost certainly existed there.
    If that conflicts with the accepted climate model for early Mars, throw out the climate model and start again!! Don't try to throw out the evidence for liquid water over the eons, because it just won't go away!

    I recently posted about a new stellar evolution theory (again I can't recall where) which maintains that our Sun was actually hotter in its early history than it's given credit for. It gradually cooled over the first 1 or 2 billion years as its nuclear fires settled down, and then began its current inexorable increase in output which will ultimately make even Earth uninhabitable.
    This theory hasn't been accepted yet - science is slow to adapt at times! But it would very neatly explain how early Mars maintained a warm wet climate, without recourse to impossibly complex atmospheric models involving up to 5 bars of CO2 and thick clouds of heat-retaining CO2 crystals!! Occam's Razor dictates that we take the least complex explanation available to us. For me, it's blatantly obvious which explanation is simpler!

    Don't despair! I'm quite sure this latest hypothesis about Mars is full of holes and won't ... [b:post_uid7]hold water![/b:post_uid7]
    GROAN ... !!
                                           big_smile


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#32 2002-12-07 06:32:05

Byron
Member
From: Florida, USA
Registered: 2002-05-16
Posts: 844

Re: H20, where'd it go? - What happened to Marsian water?

Go get 'em, Shaun! 

I'm with you all the way on this one...

Anyone who's had the opportunity to own that wonderful MOLA globe of Mars -:you and I, for one:- can plainly see that Mars once had a watery past, and I just can't imagine why so many people are attempting to disprove that Mars once had rivers, seas, etc...   ???

B

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#33 2003-03-01 11:16:25

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: H20, where'd it go? - What happened to Marsian water?

[color=#810541:post_uid2]*Don't eat pink snow? 

http://skyandtelescope.com/news/current … _881_1.asp

If, by chance, someone else has previously posted this article, my apologies...it's hard to keep track of them all.  cool

--Cindy[/color:post_uid2]


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#34 2003-03-01 16:29:58

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Wow Cindy, I think the more interesting thing from that article is the bit about there only being 0.36 millibar of CO2 frozen! That's horrible for terraformers![/color:post_uid0]


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#35 2003-03-01 20:10:31

soph
Member
Registered: 2002-11-24
Posts: 1,492

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]I actually saw an article that suggested that this may be better for terraformers. 

In any event-this news is not all that terrible as it's been made out to be.  Most of the CO2 was always expected to come from the regolith, not from the caps.  We know there is a large fraction of Earth pressure's worth of CO2 in the regolith, but we can't say just how much.[/color:post_uid0]

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#36 2003-03-01 22:39:10

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Hmm, I'd always thought the common terraforming argument was to melt the CO2 ice caps, which would increase the atmosphere by a lot of milibars.

I think Robert mentioned that in another thread.[/color:post_uid0]


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#37 2003-03-02 00:46:27

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]This subject led to quite a bit of discussion over at "Terraformation. Water, not CO2."
    Soph is quite correct that most of any future CO2 atmosphere produced by terraformers was always expected to come from the regolith. Only tens of millibars of CO2 were ever expected to come from the south polar cap, while hundreds were hoped to exist in the soil.

    I'm not sure, though, whether the recent discovery of widespread near-surface water ice might change the experts' views on this(? ). We've been told that the instrument used to detect the shallow water ice was unable to penetrate the CO2 'hood' over the far northern latitudes in winter, which is why we had to wait until late 2002 to find out about the large reservoirs in the northern hemisphere.
    When the CO2 hood disappeared, does the fact that this instrument was then able to detect the water ice indicate that there is little or no CO2 in the regolith to block the neutron emission from the water? Or is the CO2 expected to be deeper than the 1 metre or so range of the instrument, or is the CO2 too diffuse in the soil to affect the readings anyway?

    In view of the news that there may be much less CO2  present as a more-or-less pure solid at the south pole than we used to think, I'm concerned to confirm that the reserves in the regolith are still there!!
                                          ???
    Only optimistic replies will be accepted!   big_smile

    This information that Cindy has brought to light, about the possibility that only 0.36 millibars (equivalent atmosphere) of CO2 is available as surface ice, is interesting when considered alongside the Viking lander atmospheric data.
    Viking 1 measured seasonal atmospheric pressures which varied from a minimum of 6.8 millibars to a maximum of 9.0 millibars.
    If the new figures are correct, then over 80% of that 2.2 millibar 'bulking up' of the Martian atmosphere must have come from the regolith. If it didn't come from the regolith, then the 0.36 millibar estimate must be too low by a factor of about 6!!
    If data are out by a factor of 6, then maybe they're not very valuable data(? ).

    If the great majority of the 2.2 millibar seasonal increase in Martian air pressure can come from the soil, even under the present frigid conditions, then I'm hopeful that a concerted terraforming effort would release very much greater amounts of CO2.

    My biggest worry now is that all my cheering for a watery Martian past may blow up in my face. If large standing bodies of water have existed on Mars over extended periods of time, perhaps with significant episodes of precipitation and an active hydrological cycle, then maybe much of the original CO2 atmosphere has, through chemical weathering, been irreversibly incorporated into carbonate rocks. Forever unavailable to enthusiastic terraformers!!
                                      sad

    Say it ain't so!!
    Please ... somebody ... say it ain't so!!![/color:post_uid0]


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#38 2003-06-30 06:18:56

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid14]Earlier in this topic (26th June '02) I wrote a summary of the discovery of a huge paleolake basin on Mars. The water from the 1400 mile long lake flowed northward through Ma'adim Vallis into Gusev crater.

    Since Gusev crater is now one of the landing sites for the Mars Exploration Rover missions, I thought it might be a good time to revisit 'Ma'adim Lake'!

    I found a high resolution picture of the lake at this site.
    The picture is an oblique view, facing south from Gusev toward the lake. They've exaggerated the vertical scale somewhat so as to emphasise the basin-like shape of the lake floor.
    The lake's surface area was equivalent to the area of Texas and New Mexico combined and its volume was equal to 5 times the total amount of water in America's Great Lakes!
    And this is no 'if-but-and-maybe' paleolake. They've found the unmistakable shoreline!

    As I've said before, what amazes me is that the surface of 'Ma'adim Lake' (as I call it) was some 1.5 kms above datum when water was overflowing from it into Ma'adim Vallis. This indicates to me that a substantial atmosphere must have existed at the time, even at that altitude.
    Mars must have an incredible history waiting to be discovered!
    We really need scientists there on the ground ... NOW!!
                                        smile[/color:post_uid14]


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#39 2003-06-30 06:57:19

TJohn
Member
Registered: 2002-08-06
Posts: 149

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]With this discovery and finding large patches of water ice, there should be no reason why we are not sending human explorers to Mars for permanent colonization!  The technology is here!  But I'm afraid the higher ups are unwilling to have a little backbone on sending real, live, human beings to Mars.[/color:post_uid0]


One day...we will get to Mars and the rest of the galaxy!!  Hopefully it will be by Nuclear power!!!

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#40 2003-08-12 07:24:01

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: H20, where'd it go? - What happened to Marsian water?

[color=#810541:post_uid4]*How thick are the polar icecaps of Mars, and which is larger:  Northern or southern?

--Cindy

::EDIT::  Shaun, somehow I missed your 30 June 2003 post!!  sad  Wow!

"I found a high resolution picture of the lake at this site.
   The picture is an oblique view, facing north from Gusev toward the lake. They've exaggerated the vertical scale somewhat so as to emphasise the basin-like shape of the lake floor.
   The lake's surface area was equivalent to the area of Texas and New Mexico combined and its volume was equal to 5 times the total amount of water in America's Great Lakes!
   And this is no 'if-but-and-maybe' paleolake. They've found the unmistakable shoreline!"

*That surface area equivalent is astounding...Texas alone is one mighty huge chunk of land and New Mexico is no pipsqueak when it comes to square miles/kilometers.

--Cindy[/color:post_uid4]


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#41 2003-08-12 11:08:53

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]You're looking for the Northern ice cap, Cindy; it's several kilometers thick, and during the summer is mostly water. The Southern cap is made mostly of CO2, and if you remember, it's on a shrinking cycle.

I didn't see Shaun's post, either. sad

He makes a ratehr good point about there needing to be a substantial atmosphere to support such a lake. Doesn't that idea seem to automatically debunk the ovline theory?[/color:post_uid0]


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#42 2003-08-12 11:30:38

dickbill
Member
Registered: 2002-09-28
Posts: 749

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]You're looking for the Northern ice cap, Cindy; it's several kilometers thick, and during the summer is mostly water. The Southern cap is made mostly of CO2, and if you remember, it's on a shrinking cycle.[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]Hi Josh,

I think the view of the southern cap has changed recently. Something like the top most 8 meters is actually carbon dioxide, the rest below might be water ice. This based, if I remember well, to an Odyssey temperature data showing that below 8 meters, the cap was not cold enough to be CO2 ice. And as the CO2 is shrinking, maybe the future southern cap will be ice water only soon.[/color:post_uid0]

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#43 2003-08-13 18:49:07

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid14]Thanks for the interest in "Ma'adim Lake".
    I think its importance can't be overemphasised because of the implications for Mars' earlier climate. It seems difficult to understand how Dr. Nick Hoffman's "White Mars" hypothesis can get so much publicity, while this enormous paleolake is allowed to fade into obscurity.
    I think there must be an institutionalised  bias against the notion that Mars was once a balmy watery world. As usual in scientific circles, this probably arose because so many "eminences grises' have gone for the cold, dry, lifeless scenario and have created a paradigm which will be hard to dislodge. History is full of similar scientific edifices which have had to be pulled down, painstakingly, brick by brick. This is one of the biggest drawbacks with the scientific method - the human factors of pride and intransigence hampering the principle of objectivity.
    [Oops, sorry ... there I go with the soap-box routine again!!!   big_smile  ]

    Incidentally, I owe you an apology for an error in my reporting of the computer-generated image of Ma'adim Vallis etc.
    The view should be described as "facing [b:post_uid14]south[/b:post_uid14] from Gusev toward the lake".
    Sorry!   sad[/color:post_uid14]


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#44 2003-08-13 21:14:56

Free Spirit
Member
Registered: 2003-06-12
Posts: 167

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Thanks for the interest in "Ma'adim Lake".
    I think its importance can't be overemphasised because of the implications for Mars' earlier climate. It seems difficult to understand how Dr. Nick Hoffman's "White Mars" hypothesis can get so much publicity, while this enormous paleolake is allowed to fade into obscurity.
    I think there must be an institutionalised  bias against the notion that Mars was once a balmy watery world. As usual in scientific circles, this probably arose because so many "eminences grises' have gone for the cold, dry, lifeless scenario and have created a paradigm which will be hard to dislodge. History is full of similar scientific edifices which have had to be pulled down, painstakingly, brick by brick. This is one of the biggest drawbacks with the scientific method - the human factors of pride and intransigence hampering the principle of objectivity.
    [Oops, sorry ... there I go with the soap-box routine again!!!   big_smile  ]

    Incidentally, I owe you an apology for an error in my reporting of the computer-generated image of Ma'adim Vallis etc.
    The view should be described as "facing [b:post_uid0]south[/b:post_uid0] from Gusev toward the lake".
    Sorry!   sad[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]Shaun are you telling me that all of those teachers I had in school were wrong when they told us younglings that science is nothing but the search for truth and is the perfected form of human reasoning that knows no bias?   My teachers said all scientists strictly adhere to the scientific method and that it is officially bias-proof.  I don't think my sixth grade teacher would have given you very high marks in science.  :;):[/color:post_uid0]


My people don't call themselves Sioux or Dakota.  We call ourselves Ikce Wicasa, the natural humans, the free, wild, common people.  I am pleased to call myself that.  -Lame Deer

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#45 2003-08-14 12:40:08

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: H20, where'd it go? - What happened to Marsian water?

[color=#810541:post_uid0]

Shaun are you telling me that all of those teachers I had in school were wrong when they told us younglings that science is nothing but the search for truth and is the perfected form of human reasoning that knows no bias?   My teachers said all scientists strictly adhere to the scientific method and that it is officially bias-proof.  I don't think my sixth grade teacher would have given you very high marks in science.  :;):[/quote:post_uid0]
*There's no such thing as being absolutely bias-free.  However, I've known (from personal experience) plenty of religions and spiritualities which claim to be bias-free and absolutely open minded...until they are challenged, that is; even if *politely* challenged, and even if in an *indirect and sincere* fashion from "fellow seekers"; then the biases start showing (I know this from personal experience over years:  "Been there, done that").  smile

Anyone who says science is perfect, bias-free, etc., is either a fool, lying or just plain confused.  Every facet of human expression and every human being has some level of bias:  Somehow, and in some form.  This is unavoidable; it's part of living and experience.

However, extremes of bias are another matter entirely; not healthy, often destructive (no matter where it manifests).

IMO, however, science is >less< biased than religion and/or spirituality, because science insists on objective analysis, experimentation, openness and sharing of results/tests/datum, etc.  IMO, science is also more willing to admit mistakes and try again; it's more flexible and intellectually honest.

I'm always amazed at the various religious/spiritualist personalities (celebrities/"big-shots") who accuse science and scientists of being arrogant, inflexible, narrow-minded, one-dimensional, on and on...when in fact that is precisely what the accusers are, or tend to be (projection of fault).  How often have we heard religious/spiritual extremist types refer to nonbelievers as "heretics," "spiritually blind," etc., and look smugly down their noses at the skeptical?  I've seen a lot more of that than I care to remember.  At the very least, these sorts of religionists/spiritualists shouldn't point fingers.

--Cindy[/color:post_uid0]


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#46 2003-08-14 13:01:30

dickbill
Member
Registered: 2002-09-28
Posts: 749

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Shaun,

In the hypothesis that the early sun was colder, I remember a theory saying that the sun radiated maybe 30% of its actual value when it was in its early T-tauri stage, where do you get the power to warm Mars above the freezing point of water and get a permanent wet Mars ?
You need green housing gas, at least, but I read an article in 'Astronomy' saying that you would need so much CO2 that the scientists gave up on this idea.
Between your position and Hoffman, there is the position of those who believe that transient warmings (several thousand years), triggered by meteorit impact or volcanic eruption, might have been enough to account for the floodings and the paleolakes.[/color:post_uid0]

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#47 2003-08-14 14:19:57

Almir
Member
From: Brasília-DF, Brasil
Registered: 2003-02-17
Posts: 19

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Another hypothesis:

An explanation for flowing, liquid water on ancient Mars
http://www-news.uchicago.edu/releases/9 … bert.shtml[/color:post_uid0]

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#48 2003-08-14 20:36:39

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid4]There are indeed many aspects of Mars today which seem paradoxical.
    How do you reconcile the early warm wet period with the faint young Sun? How do you reconcile what looks like large recent lava flows with a small planet which should have lost its internal heat by now? How can you have northern plains, largely bereft of recent impact craters and hence apparently young, which look suspiciously like an ocean bed - when you can't possibly have had an ocean in recent Martian history? How can frequent flows of large quantities of liquid water from Argyre, north via Uzboi and Ares Valles, into Chryse through much of Mars' history be explained when Mars is purported to have been frozen solid for at least 3 billion years?

    There's something wrong with our understanding of the red planet ... something fundamentally wrong!
    My view is that we're standing here with a few pieces of a jigsaw in our hands, congratulating ourselves for having a pretty good understanding of how Mars evolved. It seems to me there are some crucial pieces of this puzzle missing and we're misinterpreting the entire picture.
    I think Mars is considerably more complicated than we realise.

    Dickbill, some time ago here I mentioned a piece of maverick research which challenged our current theory of how the Sun behaved during its first 1 - 2 billion years. I can't remember the source now but the new hypothesis suggested that soon after ignition the Sun burned up to 5%, or even 7%, more brightly than it does today. Over the next billion or so years, it settled back to maybe 70 - 80% its current output. Then it began its slow and steady increase in brightness which continues today and will ultimately make our own planet uninhabitable.
    I've heard no more about this radical hypothesis and it could have died a natural death by now. But it would go a long way toward explaining how Mars could have been warm enough to support liquid water, and perhaps life, on its surface back at the beginning of the solar system.
    My knowledge of stellar evolution is patchy, to say the least(! ), so I can't be sure of what I'm suggesting. But a flaw in our knowledge of how stars evolve seems a less complex way of explaining Mars' surface than recourse to super-exotic atmospheres of partially condensed CO2! We should remember Occam (or is it Ockham? ) and his razor. The more complicated an explanantion of anything gets, the less likely it is to be accurate.

    In summary, I agree with those of you who express puzzlement at the enigma of Martian history. We very definitely have an awful lot to learn - and no mistake!!   ???[/color:post_uid4]


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#49 2003-08-15 16:28:15

dickbill
Member
Registered: 2002-09-28
Posts: 749

Re: H20, where'd it go? - What happened to Marsian water?

[color=#000000:post_uid0]Dickbill, some time ago here I mentioned a piece of maverick research which challenged our current theory of how the Sun behaved during its first 1 - 2 billion years. I can't remember the source now but the new hypothesis suggested that soon after ignition the Sun burned up to 5%, or even 7%, more brightly than it does today. Over the next billion or so years, it settled back to maybe 70 - 80%[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0](after a small electrical problem....)

I remember Your post Shaun. I guess the T-Tauri theory is based on statistic: Astronomers study stars with similar mass and composition that the sun and observe that these stars, in their early life, radiates less energy than similar, but older, stars. The mass is really the birth mark of a star, but the composition plays a role. I 've read that the sun has a higher metallicity than stars of similar mass, so, maybe, you are right and the early sun was not so faint, due to small differences.


Almir,  I quote a passage of your link:
"Pierrehumbert collaborated with French climatologist François Forget, from the Laboratoire de Météorologie Dynamique du CNRS in Paris. "
That theory must be true then ! (just kidding).
The authors describes early martian thick CO2 clouds wich re-emit (I don't know if re-emit is the right term, reflect is better maybe ?) Infra red radiations while they reflect the visible light from the sun. Thus for these researchers, the early Mars surface was in the night, but a warm night... That's a very interesting theory, I am sure we gonna hear more about it.
Thanks for the link.[/color:post_uid0]

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