A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » SETI
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Radiative Habitable Zones in Martian Polar Environments



 
 
Thread Tools Display Modes
  #1  
Old July 14th 05, 01:14 PM
Joseph Lazio
external usenet poster
 
Posts: n/a
Default Radiative Habitable Zones in Martian Polar Environments

In this morning's astro-ph:

Paper: astro-ph/0507317
Title: Radiative Habitable Zones in Martian Polar Environments
Authors: C. Cordoba-Jabonero, M.-P. Zorzano, F. Selsis, M. R. Patel and C. S.
Cockell
Comments: 44 pages, 8 figures
Report-no: CAB-lcasat/04057
Journal-ref: Icarus 175 (2005) 360-371
DOI: 10.1016/j.icarus.2004.12.009

The biologically damaging solar ultraviolet (UV) radiation (quantified
by the DNA-weighted dose) reaches the Martian surface in extremely
high levels. Searching for potentially habitable UV-protected
environments on Mars, we considered the polar ice caps that consist of
a seasonally varying CO2 ice cover and a permanent H2O ice layer. It
was found that, though the CO2 ice is insufficient by itself to screen
the UV radiation, at 1 m depth within the perennial H2O ice the
DNA-weighted dose is reduced to terrestrial levels. This depth depends
strongly on the optical properties ofthe H2O ice layers (for instance
snow-lile layes). The Earth-like DNA-weighted dose and
Photosynthetically Active Radiation (PAR) requirements were used to
define the upper and lower limits of the nortern and southern polar
radiative habitable zone (RHZ) for which a temporal and spatial
mapping was performed. Based on these studies we conclude that
phtosynthetic life might be possible within the ice layers of the
polar regions. The thickness varies along each Martian polar spring
and summer between 1.5 m and 2.4 m for H2= ice-like layers, and a few
centimeters for snow-like covers. These Martian Earth-like radiative
habitable environments may be primary targets for future Martian
astrobiological missions. Special attention should be paid to
planetary protection, since the polar RHZ may also be subject to
terrestrial contamination by probes.

( http://arXiv.org/abs/astro-ph/0507317 , 888kb)

--
Lt. Lazio, HTML police | e-mail:
No means no, stop rape. |
http://patriot.net/%7Ejlazio/
sci.astro FAQ at http://sciastro.astronomy.net/sci.astro.html
  #2  
Old July 15th 05, 10:47 PM
Brad Guth
external usenet poster
 
Posts: n/a
Default


At 30 mw/m2 worth of a near surface geothermal radiative heat flux and,
at times not actually all that much better contributed from the sun, a
Mars polar habitat zone that's covered by such a thick crystal
composite of mosly CO2/dry-ice had best plan upon forgetting about
utilizing whatever safe levels of UV by going deep, at least a km if
not deeper and, taking along a good cash of plutonium for energy and
auxiliary radiative heat to boot.

This fresh SETI topic (as generated by Alfred A. Aburto Jr.) "Life in
solid ice" as having provided us with this following research link
that's sharing absolutely terrific information about the potentials of
their being other such life within ice;
http://xxx.lanl.gov/ftp/q-bio/papers/0507/0507004.pdf

With a little spare (imported) energy one can easily generate
artificial amounts of UV-b and UV-a (perhaps affordably as great as 1
w/m2 per scientific working habitat), not to mention the
secondary/recoil worth of visible plus whatever waste thermopile IR
heat spectrums as well.

Suggesting that Martian life somehow became naturally evolved as
becoming sub-frozen sequestered DNA/RNA, as for their relatively abrupt
environment shift upon Mars getting summarily pulverised, as for their
having to survive by going deep into a sub-layer of H2O/ice isn't
exactly all that doable unless some form(s) of applied (ETI to us)
technology are responsible. Dormant if not dead forms of sequestered
Martian life, little more than microbes and/or spores trapped deep into
the likes of H2O/ice or even salty/comet deposited ice is doable,
although especially doable under that ice if there's any remains of an
ocean or even slight pools of geothermally sustained environments which
you'd think should be chuck full of such Martian life. Although, I'm
thinking mostly of that form of sequestered life as having become
non-photon and thus mostly chemically reactive, which we haven't much
of anything similar upon Earth until going extremely deep into our
oceans, though even that form of life has formed viable ways of
generating their own photons, and/or of having shifted their biological
and visual evolution toward the geothermal IR spectrum.

Robotically going for such deep Martian life as a continuing level of
our nearly mad science research is going to remain as horrifically
spendy, as well as each mission and for all those nice folks employed
will be continually consuming talents, resources and thereby polluting
for mother Earth in far more ways than the mere fire and brimstone
launch phase, not to mention potentially lethal aspects if our pro-Mars
or bust wizards actually manage to retrieve such items from Mars.
Humanly going for the likes of Mars is absolutely insane beyond the
"high standards and accountability" standards of even our "so what's
the difference" LLPOF level of incompetence and arrogance represented
our resident warlord(GW Bush), that is unless we've established such a
technological and scientific quest as being a one-way ticket to ride,
or by way of having established their lifetime safe-house as situated
upon our moon.

Of course, going for Venus is almost too easy, especially when at times
it's merely a little better than 100 fold as far off as our moon, as
well as there's no apparent need for a given mission (robotic or
otherwise) having to bring along spare energy. Obviously there's not
much chance in hell of there being any ice upon Venus. However, with
such easily available green/renewable and thus squeaky clean resource
of energy there's no apparent nor insurmountable limits as to what can
be artificially sub-frozen, or otherwise easily processed into just
about anything you can imagine. Thus robotically and even humanly
accessible is where the relatively hot but not actually all that nasty
environment of Venus has been doable, especially if you're situated as
somewhat elevated and migrating yourself from time to time as for
residing within the extensive season of nighttime, within an
environment that's corrosion free, essentially fire-proof and
absolutely crystal clear (other than for geothermal S8 venting) for a
good 25+km in all directions and, actually only a wee bit dark to human
vision but nocturnally and/or applied technology making the nighttime
season just fine and dandy.

Since terrestrial ice doesn't so easily just happen for the inner most
creation of planets. Unlike a mostly sub-frozen, easily pulverised and
TBI to death Mars, a sufficient volume of raw ice is exactly what a
geothermally hot Venus needs if to accommodate the wet forms of life as
we've known about, just as it was the necessary influx of such massive
snowballs and/or horrific shards of icebergs as pulverised away from an
icy proto-moon upon initial and subsequent secondary impacts generating
such nasty icy spacebergs that eventually gave mother Earth a badly
needed cooling-off shot in the dark at creating and sustaining life as
we know it, that is unless our sun started itself up gradually instead
of any result of a big or little bang, or having arrived somewhat after
the fact seems almost impossible.

A couple of related although officially banished/taboo topics:
Getting Sedna into orbiting Venus
http://groups-beta.google.com/group/...74d 05e31f6ee
MOON Physics at 1% the cost of doing Tempel-1
http://groups-beta.google.com/group/...75214f0e833df4
~

Venus Life, a Township, Bridge and ET/UFO Park-n-Ride Tarmac:
http://guthvenus.tripod.com/gv-town.htm
Russian/China LSE-CM/ISS (Lunar Space Elevator)
http://guthvenus.tripod.com/lunar-space-elevator.htm
Other Life on Venus, plus sub-topics; Brad Guth / GASA-IEIS
http://guthvenus.tripod.com/gv-topics.htm

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
New Martian Meteorite Found in Algeria: NWA 3171 Ron Astronomy Misc 0 August 20th 04 10:07 PM
Planetary Systems With Habitable Earths? Rodney Kelp Policy 6 April 2nd 04 02:32 PM
ESA's Martian weather report (Forwarded) Andrew Yee Astronomy Misc 0 January 15th 04 05:10 PM
Mars Is Melting Ron Baalke Science 0 August 7th 03 09:19 PM


All times are GMT +1. The time now is 08:44 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 SpaceBanter.com.
The comments are property of their posters.