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antoniseb
2005-Feb-18, 03:57 PM
Here's a New Scientist Story that we'll probably see here in a few hours:
Martian Water (http://www.newscientist.com/article.ns?id=dn7026)

Essentially it is a report of observations from the European Mars Orbiter showing a large region of Northern Hemisphere Mars with a strong spectral signiture of gypsum.

Betelgeuse
2005-Feb-18, 09:10 PM
Other images from the Omega instrument reveal that the water-related minerals examined close-up by Opportunity were, literally, just a scratch on the surface

Presumably, what he's implying is that there could be room for depth for these water-related minerals?

Duane
2005-Feb-18, 10:30 PM
Yes, I believe that is his point. It should be noted that Mars Express's radar will help to determine depth, at least to a few meters.

contact
2005-Feb-22, 05:14 PM
Hey, read this!
It's from the Server of the Geological Institute
at the University of Berlin

http://www.geoinf.fu-berlin.de/

THE MARS EXPLORER FOUND A FROZEN SEA THE SIZE
OF THE NORTH SEA ON ELYSIUM REGION ON MARS!

Fraser
2005-Feb-22, 05:50 PM
SUMMARY: The European Space Agency's Mars Express spacecraft has uncovered evidence for a massive sea of water ice in warm conditions near Martian equator. Since temperatures in this region can rise above freezing, it could be a good location to look for life. The frozen sea measures 800 x 900 km across (497 x 559 miles), varies up to 45 metres (150 feet) deep. Previous observations by Mars Express of methane levels do match up to this newly discovered ice, so it builds on the theory that there could be microbial life living underneath Mars' freeze dried and irradiated surface.

View full article (http://www.universetoday.com/am/publish/frozen_sea_water_mars.html)

What do you think about this story? Post your comments below.

Guest
2005-Feb-22, 05:55 PM
great finding, so when are we going to send a lander to drill below the surface ? :)

alfchemist
2005-Feb-22, 05:56 PM
Hi, Contact! I hope there's an english version of the article. :D

antoniseb
2005-Feb-22, 06:02 PM
Wow! what a great picture.

That is a lot of water. It could supply a city for quite a while.

contact
2005-Feb-22, 06:09 PM
Originally posted by alfchemist@Feb 22 2005, 07:56 PM
Hi, Contact! I hope there's an english version of the article. :D

Yes, damn (sorry!), I was too slow!
Fraser posted it right now:

http://www.universetoday.com/am/publish/fr...rs.html?2222005 (http://www.universetoday.com/am/publish/frozen_sea_water_mars.html?2222005)

Oh how I like it to live in these days of the Dawn of the Space Age!

contact
2005-Feb-22, 06:36 PM
Originally posted by antoniseb@Feb 22 2005, 08:02 PM
That is a lot of water. It could supply a city for quite a while.
If this holds true, then from now on
everything is possible on Mars for our
species. Where is water there will be
oxygen, and hydrogen. Maybe nuclear
fusion will be possible. Ice hockey will
be possible, too. :D

wstevenbrown
2005-Feb-22, 11:36 PM
:D :D :D :D :D S.

antoniseb
2005-Feb-22, 11:39 PM
Originally posted by contact@Feb 22 2005, 06:36 PM
from now on everything is possible on Mars for our species. Where is water there will be oxygen, and hydrogen.
There's plenty of Carbon and Oxygen. I don't recall hearing much about Nitrogen on Mars. We might have to import that.

scorpio711
2005-Feb-22, 11:45 PM
wow ! Another candidate for the future NASA MSL mission !!!! And all these discoveries will raise general interest for Mars even higher... which helps for getting funds :) !!!!
Scorpio

alfchemist
2005-Feb-23, 06:29 AM
This is exciting indeed! Maybe there are several more of these features. This find is redefining our notion about mars being bone dry. If methane signature is detected here, the feature must be imperfect and has some fractures, some good sites to drill rather than doing it ramdomly. Methane distribution map should locate these sites

alfchemist
2005-Feb-23, 08:10 AM
Hi, Contact! that's ok! I'm sure some members of UT who know the language appreciate your article. I would, if it's written in spanish so i get to practice my spanish language skills. The New Scientist's article point to a northern hemisphere site and evidences of gypsum while article posted by fraser points to an area near the equator where temperature could go up above 273K. I'm confiednt there are more sites near the equator similar to that discovered. Soon, we will know that mars indeed show some semblance of earth in its geologic past

Eric Vaxxine
2005-Feb-23, 09:20 AM
What about the radiation, surely that kills all hope of life?

piersdad
2005-Feb-23, 09:44 AM
an amazing discovery.
radiation may even help some forms of life.
if the 'sea' is deep there could be pockets of un frozen water beneath and life there would be protected.
i look forward to more news about this martian sea

Essel
2005-Feb-23, 01:16 PM
Eric Vaxxine Posted on Feb 23 2005, 09:20 AM

What about the radiation, surely that kills all hope of life?

"there could be microbial life living underneath Mars' freeze dried and irradiated surface."

It is not very clear whether 45m thickness of ice still exists, this could be another shield for radiation.

Can anyone guide us on the depth of penetration levels of radiation expected on mars sub-surface or below water-ice?

SCHNECK
2005-Feb-23, 01:35 PM
Snow Ball Mars ?

Ola D.
2005-Feb-23, 04:21 PM
Originally posted by contact@Feb 22 2005, 06:36 PM
everything is possible on Mars for our
species. Where is water there will be
oxygen, and hydrogen.
I'd rather stay on Earth ;)
Exciting discovery!

scorpio711
2005-Feb-23, 04:59 PM
Concerning resistance to radiation, we know at least of one extremophile - deinoccocus radiodurans - that is extremely resistant to radiations.

I suggest you have a look at:
http://www.lsu.edu/lsutoday/030627/pagetwo.html

and I extract here the interesting text:

"[...] Battista got the grant because he is one of the world’s foremost researchers on the little bug Deinococcus radiodurans – translated as the “amazing radiation-enduring berry.” Deinococcus, which was originally discovered in 1956 when it survived food sterilization tests, is one of the hardiest organisms known. It can withstand astonishingly large amounts of cold, vacuum, dormancy, oxidative damage, dessication and radiation, making it the perfect test organism for a form of life that might survive the hostile conditions of Mars.

Battista subjected colonies of Deinoccocus under different conditions to gamma radiation. The toughest to kill were those in an environment similar to what might be expected on Mars. Battista dried them and packed them in minute fussures in rocks the same size and composition the Martian samples are expected to be. He discovered that it took 20 million rads to kill dried specimens of the cells; by contrast, a mammalian cell won’t survive 100 rads. [...]"

Scorpio

Eric Vaxxine
2005-Feb-23, 05:21 PM
Thanks everyone, appreciate your answers.

John L
2005-Feb-23, 10:59 PM
They wanted to send that Phoenix lander to the pole, but this may be a better destination. It is supposed to drill into the polar ice, but why not here instead. And I agree the MSL would do well here. Maybe we can even do a new mission with ESA to get some comprehensive science done. We can supply a nuclear power source for a long-lived probe and they can provide some of the instruments and maybe a deep drill. Maybe it can be built on an MSL style chasis, something proven...

Duane
2005-Feb-24, 05:39 PM
I like that idea John. It would be cheaper than the MSL as well, given the redundancy of the systems.

scorpio711
2005-Feb-24, 06:00 PM
I agree w/ both of you, John & Duane !!!
ESA has been so far quite "short and tight" regarding budget and funding, but I hope that the big successes of Mars Express then Huygens (not counting Ariane 5 ECA) will raise interest thus will raise funding too.

By the way, I know this has nothing to do with this thread and discussion, but I noticed that Germany was not part of the Aurora program (long term space exploration w/ short term programs and missions) of the ESA, which surprised me a little. Does anybody know why?

Scorpio

antoniseb
2005-Feb-24, 06:44 PM
A friend of mine asked me "How do they know it's water-ice?".
The article didn't really say, but my explanation was this:

It is clearly a block of something that was many miles across, and was liquid, and then froze, at temperatures possible on Mars' Equator. This leaves few chemical options for state and quantity. Things that might freeze at slightly above this temperature include some alamgam of Mercury and Galium, neither of which is abundant enough to supply the many cubic miles of substance we see here. Ammonia, Methane, CO2, are all common enough, but have the wrong temperatures.

OK, that's what I said. Does anyone have a better explanation for how they know [or why they think] it's water?

piersdad
2005-Feb-24, 07:06 PM
the shape of the meteor craters shows that the surface was melted on impact and is unlike other craters which are not so smooth in texture.
theu appear to have melted the ice and the warm debris has refrozen and not changed since the initial impact.
they look like a pic of a pebble that has just penitrated the water

alfchemist
2005-Feb-24, 08:06 PM
From the way I see it, its the craters that were formed first and then filled to their "neck" with something that froze around them. As for the composition of the frozen substance, it seems composite, unless some ice are older than the others. It's very inhomogeneous.

Essel
2005-Feb-25, 11:57 AM
antoniseb Posted: Feb 24 2005, 06:44 PM

A friend of mine asked me "How do they know it's water-ice?".
The article didn't really say, but my explanation was this:

Anton, a lot of time has been spent in investigation prior to the release. They must have used the plethora of scientific payload that Mars Express carries to reconfirm the find. Mars Express Orbiter scientific payload includes:

Surface/subsurface instruments
HRSC (High Resolution Stereo Camera)
OMEGA (Visible and Infrared Mineralogical Mapping Spectrometer)
MARSIS (Sub-surface Sounding Radar Altimeter)

Atmosphere/Ionosphere instruments
PFS (Planetary Fourier Spectrometer)
SPICAM (Ultraviolet and Infrared Atmospheric Spectrometer)
ASPERA (Energetic Neutral Atoms Analyser)

Radio link
MaRS (Mars Radio Science Experiment)

Out of the above, following are of significance to analyze the sea of water ice recently found:

“High Resolution Stereo Camera (HRSC):
The HRSC is imaging the entire planet in full colour, 3D and with a resolution of about 10 metres. Selected areas could be imaged at 2-metre resolution.”

This instrument was clearly used as apparent from the high resolution pictures.

“OMEGA Visible and Infrared Mineralogical Mapping Spectrometer:
OMEGA maps the surface composition in 100 metre squares. It determines mineral composition from the visible and infrared light reflected from the planet's surface in the wavelength range 0.5-5.2 microns. Key investigations could include: iron content of the surface, the water content of the rocks and clay minerals and the abundance of non-silicate materials such as carbonates and nitrates.”

There is a clear use of this instrument as mentioned in your post featuring new scientist.

But now, new data from the Omega visible and near-IR imaging spectrometer onboard Mars Express has found a large region - 60 kilometres by 200 km - that shows the clear spectral signature of calcium-rich sulphates, probably gypsum. This means that at least a portion of that northern "ocean" area was indeed covered by standing water for a long time.


“MARSIS Sub-Surface Sounding Radar Altimeter:
MARSIS can map the sub-surface structure to a depth of a few kilometres. The instrument's 40-metre long antenna will send low frequency radio waves towards the planet, which will be reflected from any surface they encounter. For most, this will be the surface of Mars, but a significant fraction will travel through the crust to be reflected at sub-surface interfaces between layers of different material, including water or ice. “

It is not known whether the above instrument was used.

May be we should learn about it today from esa: “Mars Express media briefing on Friday 25 February: After a week of major announcements about Mars and the results from ESA’s Mars Express mission, ESA will host a press briefing on 25 February to present the main conclusions of the First Mars Express Science Conference.”

piersdad
2005-Feb-25, 06:38 PM
gee thanks for your expert reply here Essel.
im looking forward to more news from mars

Duane
2005-Feb-25, 10:35 PM
MARSIS was not used, it is due for deployment in early May. Its deployment was delayed because they are concerned the springed-loaded deployment actuator may be too powerful and cause damage to the craft.

David S
2005-Feb-26, 10:24 PM
Doesn't the Mars Express Orbiter have an insturment on board that detects hydorgen? I assumed that was how they knew it was water, because they detected hydrogen there.

Also, I must say that the case for life on Mars grows stronger eveyday. The Methane discovery a few months ago was huge by itself, but now that we know that the methane is appearing from an area where there is probably liquid water for some of the Martian year makes Mars a much more interesting place.

Just out of curiosity, does anyone know where this site is in relation to other previous landers we've sent to Mars, such as Viking, Pathfinder, ect?

alfchemist
2005-Feb-27, 07:42 AM
Hi, AstroWannabe! They don't detect water by its hydrogen composition (H2O). It's the molecular signature in the IR range. From the list given by Essel, I think it's the infrared spectrometer they used to detect water probably on the reflectance mode.The water signature is in the mid -IR range but since Essel said the instrument is from Visible to near-infrared, that should cover it.

Guest
2005-Feb-27, 08:23 AM
Oh, let me correct myself. I was thinking of far-infrared. They may be able to adjust the filter to cover the whole range of Infrared.

Alfchemist