New Mars Forums

Palomar

Member

From: USA

Registered: 2002-05-30

Posts: 9,734

Re: Glacial Cycles/Ice Caps

http://www.spacedaily.com/news/mars-wat … html]Click

*Rather indepth.  I'll have to re-read it before commenting.  Is early a.m. currently.

--Cindy

---

We all know [i]those[/i] 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)

Shaun Barrett

Member

From: Cairns, Queensland, Australia

Registered: 2001-12-28

Posts: 2,843

Re: Glacial Cycles/Ice Caps

"A moon, a moon; my martian kingdom for a massive obliquity-stabilising moon!"
                                       

---

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

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,820

Re: Glacial Cycles/Ice Caps

Yup a much larger moon would stabilize the orbiting planet from the wandering poles. But how large, of what mass to distance from the planet and at what rotational speed would it take? Would this also be enough to start up the magnetic fields from the internal core that is cold at this time or would we need to add a few nukes to get things started by warming the internals up.

Rxke

Member

From: Belgium

Registered: 2003-11-03

Posts: 3,669

Re: Glacial Cycles/Ice Caps

Wow...

This would eplain a lot of surface features, and they would then not point to a wet past lasting very long per se...

As they say: ice possibly hundred meters deep... Now imagine an axis shift, that ice is 'all of a sudden' (geologically speaking,) much closer to the equator... Being so deep, thus isolation quite good, it takes awhile for increased insolation to do its work, and cause it to melt... Slowly pressure rizes... And then all of a sudden the subsurface water 'breaks out' to the surface violently.

...Only to sublime quite quickly and getting deposited on the new poles...

BTW: fast-changing obliquity:"the current average value which is of ~25.19 deg"

Now im *very* certain, when i was a snotty nosed kid, it was closer to 24deg, in the textbooks    And that was not so long ago, heh.

RobS

Banned

From: South Bend, IN

Registered: 2002-01-15

Posts: 1,701

Website

Re: Glacial Cycles/Ice Caps

I think it's fascinating that Mars does this axial tilt thing every few million years. It explains the crater-dating of the current polar terrains at less than a million years (something I always found unbelievable, but now it makes sense). It also means that there may be fossilized snowdrifts at the Martian equator buried under dunes and dust deposits, which will be very useful to future settlers. It also means water is more present in the geology of the equator, so the regolith is not as dried out as people had thought. All around, this is great.

         -- RobS

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,820

Re: Glacial Cycles/Ice Caps

What I wonder more about with regards to the poles shifting would be did they happen at the same time as when Earths did?

Rxke

Member

From: Belgium

Registered: 2003-11-03

Posts: 3,669

Re: Glacial Cycles/Ice Caps

All around, this is great.

Not all around. Building on permafrost is iffy to say the least, heehee.

But in a whole, yessss. Also: good for life?

I'd say yes. It's subsurface ice, ok, but it's still water, and possibly quite significant amounts. Some stuff survives in sub-freezing temps, as long as they have water... etc etc...

Shaun Barrett

Member

From: Cairns, Queensland, Australia

Registered: 2001-12-28

Posts: 2,843

Re: Glacial Cycles/Ice Caps

The changing obliquity thing may cast further doubt on indigenous martian life-forms, though.
    We must assume Mars never had a large stabilising moon, so large obliquity changes, with the accompanying extreme climatic shifts, must have made for a less conducive environment for life.
    Once Earth's Moon had moved far enough away to reduce the initially monstrous tides to manageable proportions, Earth must have been climatically much more stable than Mars. If so, it looks more likely, I guess, that life probably (not definitely) originated here rather than there.

    Due to impact transfer, though, I'm still confident that terrestrial life has found its way to Mars on countless occasions over the eons, finding niches and evolving to withstand the conditions. I still think we'll find basically familiar life on Mars - more the bacterial kind than the Homer Simpson kind, I mean!
                                           

---

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

ERRORIST

Member

From: OXFORD ALABAMA

Registered: 2004-01-28

Posts: 1,182

Re: Glacial Cycles/Ice Caps

To me it proves the existance of ground water and thus spring water may exist like the inside walls of Endurance crater may have.