Mars Water Debate Still Rages

Page 7 - Seeking answers about space? Join the Space community: the premier source of space exploration, innovation, and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier.
Status
Not open for further replies.
A

alexblackwell

Guest
Published online today in the <i>Journal of Geophysical Research-Planets</i>:<br /><br /><i>Jernsletten, Jørn Atle</i><br /><b>A topographic test for the existence of ground ice in the walls of Coprates Chasma, Mars</b><br /><i>J. Geophys. Res</i>., Vol. 109, No. E12, E12004<br />10.1029/2004JE002272<br />15 December 2004<br />Abstract
 
R

robnissen

Guest
I know that ice typically turns to vapor on Mars due to atmospheric pressure without going through a liquid phase. That being said, is it possible that if the frost is covered by dust that it could perhaps then go through a liquid stage and seep into the soil?
 
A

alexblackwell

Guest
<i>Does the discovery of these layers deal a fatal blow to a purely lucastrine hypothesis for Meridiani?</i><br /><br />Personally, I don't think so, since "lacustrine" can incorporate standing bodies of liquid water of varying depths. Squyres's interpretation does, to some extent, support the opinions of many on the MER science team that the Opportunity landing site was <i>not</i> the location of a <i>deep water</i> environment.<br /><br />As others have noted elsewhere, the apparent regional and local topography at Meridiani Planum really does not favor an enclosed basin that could contain much more than shallow standing bodies of liquid water. And there are no obvious shorelines, tombolos, spits, etc. Indeed, one might consider just as plausible Squyres's early, if not solitary, alternative speculation of an ice-covered, shallow standing body of water there.<br /><br />That said, however, I would also hasten to add that, whatever it really represents, Meridiani Planum probably does not tell us much, if anything, about <i>Noachian</i> Mars, when, presumably, conditions were more favorable, if at all, for larger, less ephemeral bodies of liquid water.<br /><br />But what's interesting to me is that I don't think these various views are mutually exclusive, especially if one factors in the temporal distributions of the different types of terrains supporting each.
 
A

alexblackwell

Guest
There's a new preprint available in <i>JGR-Planets in Press</i>:<br /><br /><i>Buczkowski, Debra; Frey, Herb; Roark, James; McGill, George E.</i>, — December 2004<br /><b>Buried Impact Craters: a Topographic Analysis of Quasi-circular Depressions, Utopia Basin, Mars</b><br />(2004JE002324)<br />PDF [5.3 MB]<br /><br />Note: I believe <i>JGR-Planets in Press</i> is available to non-subscribers.
 
A

alexblackwell

Guest
From the December 23/30, 2004 issue of <i>Nature</i>:<br /><br /><b>Recent and episodic volcanic and glacial activity on Mars revealed by the High Resolution Stereo Camera</b><br />G. Neukum <i>et al</i>.<br /><i>Nature</i> <b>432</b>, 971-979 (2004).<br />doi:10.1038/nature03231<br />Summary<br />Supplementary Information <br /><br />See also:<br /><br />Mars Volcanoes Possibly Still Active, Pictures Show <br />By Robert Roy Britt<br />Senior Science Writer, Space.com<br />posted: 22 December 2004<br />1:00 p.m. ET
 
A

alexblackwell

Guest
Published online today in <i>Geophysical Research Letters</i>:<br /><br /><i>Greeley, Ronald; Whelley, Patrick L.; Neakrase, Lynn D. V.</i><br /><b>Martian dust devils: Directions of movement inferred from their tracks</b><br /><i>Geophys. Res. Lett</i>., Vol. 31, No. 24, L24702<br />10.1029/2004GL021599<br />23 December 2004<br />Abstract
 
A

alexblackwell

Guest
<i>From the December 23/30, 2004 issue of <i>Nature</i>:<br /><br /><b>Recent and episodic volcanic and glacial activity on Mars revealed by the High Resolution Stereo Camera</b><br />G. Neukum <i>et al</i>.<br /><i>Nature</i> <b>432</b>, 971-979 (2004).<br />doi:10.1038/nature03231<br />Summary<br />Supplementary Information</i><br /><br />For those without access to <i>Nature</i>, a reprint (~856 Kb PDF) of the Neukum <i>et al.</i> paper is available. And, if I'm not mistaken, I believe that non-subscribers are able to access the "Supplementary Information" links at the <i>Nature</i> website (see above).
 
A

alexblackwell

Guest
Published online today in the <i>Journal of Geophysical Research-Planets</i>:<br /><br /><i>Baldridge, Alice M.; Farmer, Jack D.; Moersch, Jeffrey E.</i><br /><b>Mars remote-sensing analog studies in the Badwater Basin, Death Valley, California</b><br /><i>J. Geophys. Res</i>., Vol. 109, No. E12, E12006<br />10.1029/2004JE002315<br />28 December 2004<br />Abstract
 
A

alexblackwell

Guest
Published online today in the <i>Journal of Geophysical Research-Planets</i>:<br /><br /><i>Irwin, Rossman P., III; Howard, Alan D.; Maxwell, Ted A.</i><br /><b>Geomorphology of Ma'adim Vallis, Mars, and associated paleolake basins</b><br /><i>J. Geophys. Res</i>., Vol. 109, No. E12, E12009<br />10.1029/2004JE002287<br />30 December 2004<br />Abstract
 
D

douglas_clark

Guest
AlexBlackwell,<br /><br />Just a question from the depths of ignorance.<br /><br />Don't have access to journals, couldn't even look at affording the subscriptions, but, we know that one of the Martian poles is ice. Where's the problem? There is water, in the form of ice, on Mars. Mars had more atmospheric pressure in the past, probably had more ice, some of which might have been water. Why are scientists hung up on the obvious?<br /><br />Douglas<br /><br /><br /><br />
 
A

alexblackwell

Guest
<i>Just a question from the depths of ignorance. <br /><br />Don't have access to journals, couldn't even look at affording the subscriptions, but, we know that one of the Martian poles is ice. Where's the problem? There is water, in the form of ice, on Mars. Mars had more atmospheric pressure in the past, probably had more ice, some of which might have been water. Why are scientists hung up on the obvious?</i><br /><br />Actually, Douglas, it's a good question, and a rather fundamental one at that.<br /><br />I was going to give a fairly long-winded response; however, I felt that a better one was available. I would refer you to an interview of Steve Squyres, Principal Investigator for the MER scientific payload, on National Public Radio last March. In my opinion, he gives a good basic explanation of the whole "water on Mars" issue.
 
N

newtonian

Guest
AlexBlackwell - This may be in the thread, some quick questions:<br /><br />Temperature of ancient Mars- I thought it was hot. When would it theoretically go from too hot for water to cool enough for condensation?<br /><br />Ancient atmosphere - I assume the atmosphere left early, due to lower gravitation? However, was there an early greenhouse effect from more abundant CO2? <br /><br />Compare nebular hypothesis for origin, and hotter conditions in inner solar system accretion disk.<br /><br />Also possibly closer orbit changed by transference of angular momentum from an earlier more rapid rotation sun to more rapid revolution of planets.
 
A

alexblackwell

Guest
<i>Temperature of ancient Mars- I thought it was hot. When would it theoretically go from too hot for water to cool enough for condensation?</i><br /><br />I think I might understand your question, but could you be a little more specific?<br /><br /><i>Ancient atmosphere - I assume the atmosphere left early, due to lower gravitation?</i><br /><br />Lower gravitation was almost certainly a factor (<i>i.e</i>., to facilitate hydrodynamic escape, which was preceded by photodissociation of H<sub>2</sub>O); however, the primary cause of primoridal atmospheric loss for is thought to be impact erosion.<br /><br /><i>However, was there an early greenhouse effect from more abundant CO2?</i><br /><br />That's a widely-held view to explain landforms such as the ancient valley networks, though many have pointed out holes in the model(s). Indeed, Segura <i>et al</i>. [2002] advance a model where a long-lived greenhouse climate is not necessary, instead invoking episodic precipitation from "microclimates" stemming from major impact events on a Mars that has always been essentially cold and dry.<br /><br /><i>Compare nebular hypothesis for origin, and hotter conditions in inner solar system accretion disk.</i><br /><br />I'm not sure what you're driving at here.<br /><br /><i>Also possibly closer orbit changed by transference of angular momentum from an earlier more rapid rotation sun to more rapid revolution of planets.</i><br /><br />Though I may have missed it, I haven't seen anyone argue any type of planetary migration models for Mars, at least in the peer-reviewed literature. Do you have any references?
 
A

alexblackwell

Guest
Dolores Beasley<br />Headquarters, Washington Dec. 30, 2004<br />(Phone: 202/358-1753)<br /><br />Guy Webster<br />Jet Propulsion Laboratory, Pasadena, Calif.<br />(Phone: 818/354-6278)<br /><br />MEDIA ADVISORY: M04-213<br /><br />NASA EVENTS COMMEMORATE ROVER ANNIVERSARY ON MARS<br /><br />On Jan. 3, 2004, cheers erupted from mission control at NASA's Jet<br />Propulsion Laboratory (JPL), when the first robotic rover successfully<br />landed on Mars. Three weeks later, the second rover successfully landed<br />on the opposite side of Mars.<br /><br />One year later rovers Spirit and Opportunity have exceeded all mission<br />expectations and continue to make discoveries. The goal of NASA's Mars<br />Exploration Rover (MER) mission was to explore for a minimum of 90 days<br />to search for evidence of past water activity.<br /><br />"One Year on Mars," a special two-hour live event to commemorate the<br />mission, will be presented at JPL on Monday, Jan. 3, 2005, from 2 p.m.<br />to 4 p.m. EST. The live event, along with additional taped programming<br />and live-shot opportunities, will be aired on NASA-TV.<br /><br />At 2 p.m. EST, a news briefing will detail discoveries made in 2004,<br />and the rover's outlook for 2005. Panelists:<br /><br />-- NASA Administrator Sean O'Keefe<br />-- Dr. Charles Elachi, Director, JPL<br />-- Jim Erickson, MER Project Manager, JPL<br />-- Dr. Steve Squyres, MER Principal Investigator, Cornell University, Ithaca, N.Y.<br />-- Dr. Firouz Naderi, MER Program Manager, JPL<br />-- Dr. Jim Garvin, Chief Scientist, NASA Headquarters, Washington.<br /><br />At 3 p.m. EST, the MER team will present "Mars Stories We've Never<br />Told." This 60-minute live program will feature members recounting<br />personal experiences of the past year. The program will end with the<br />cutting of a rover "birthday cake."<br /><br />Two additional rover programs will air on NASA TV on Monday. "Twelve<br />Wheels on Mars" airs at 1 p.m. EST. This 60-minute program features<br />professional stor
 
D

douglas_clark

Guest
Alex, thanks very much for the reference. It was very interesting. Gave me a lot to think about.<br /><br />Cheers<br /><br />Douglas
 
A

alexblackwell

Guest
Call for Manuscripts<br />2nd Early Mars Conference Special Section of the <i>Journal of Geophysical Research-Planets</i>:<br /><br />Early Mars: Geologic, Hydrologic, and Climatic Evolution and the Implications for Life Manuscript submission period*: February 1 - April 15, 2005<br /><br />To help capture the scientific output of the recent 2nd Early Mars Conference, the conveners have made arrangements with <i>JGR-Planets</i> for the publication of a special section devoted to papers addressing the broad range of topics covered by the meeting. Participation in the Conference is not a prerequisite for submitting a manuscript.<br /><br />Submitted manuscripts should have a substantial Early Mars focus, but may also address terrestrial analogs and processes where there is a clear and demonstrated relevance to Mars. Papers may address any relevant aspect of Early Mars research, including: physical & chemical properties, geology, hydrology, climate, and life.<br /><br />Papers must be of a scientific (<i>i.e</i>., involving data analysis, or the presentation of new theories and interpretations, etc.), rather than engineering nature. <i>JGR-Planets</i> generally does not publish papers describing instrument designs or concepts, or any paper that might be seen as advocating a particular mission that is not yet approved. Where a question exists regarding the potential acceptability of a topic, authors should contact the editor.<br /><br />All manuscripts will go through the standard review process, and there is no guarantee that a given manuscript will be accepted for publication.<br /><br />Cover letters should reference the 2nd Early Mars Conference special section. Please feel free to suggest possible reviewers for your paper. All manuscript submittal information can be found at<br /><br />http://www.agu.org/journals/je/<br /><br />If you are planning to submit a manuscript,
 
Status
Not open for further replies.

Latest posts