Unprotected water ice on Mars!

[keermalec]

Here is clear evidence of unprotected water ice on Mars! <br /><br />Ice sublimates at 198K at martian atmospheric pressure. Therefore it can theoretically exist at high latitudes in unprotected form, which this picture apparently proves.<br /><br />This should put an end to the various quibbles over the ease of access to water on Mars. <br /><br />In the case of manned missions to Mars, easilly accessible water means much less mass to carry for life support and return propellant. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[3488]

Hi Keermalec,<br /><br />That is very true. Hopefully the Mars Phoenix Lander currently on route may find some.<br /><br />Also there is this Ice Mound in the South Polar region & this close up<br />view of the ice mound in the north 35 KM wide polar crater you have linked to, this time from MRO HiRISE.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[thereiwas]

I wonder why there is no dust on the ice.

 

[spacefire]

cause sometimes the top layer melts and runs off? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[keermalec]

Well it should sublime, not run off... Only reason I can think of for ice to remain uncovered is it arrived there not too long ago, but how? <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[keermalec]

Hm, maybe it actually snowed! If the temperature drops below 198K what little water vapour is in the air (0.03%) will necessarily condense.<br /><br />Then maybe it sublimes away when the temp goes above 198 again but not at the bottom of craters where the temperature is lower because the ground is colder and because there is less sunlight? <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[3488]

Clearly the relationship between crater floors & latitude play a part here.<br /><br />The crater you linked to, in the Mars Express HRSC image, does see full sunlight, but<br />maybe the floor only sees the sun on briefly, due to the surrounding walls?<br /><br />Just a thought.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[scottb50]

There's also the possibility it isn't water ice to begin with. It could be Carbon Dioxide, at that temperature it could be in the same physical state as water, especially if it has been frozen for a very long period, like glacier ice here. <div class="Discussion_UserSignature"> </div>

 

[keermalec]

Well the ESA comment says it is water ice. I suppose they used spectrophotometry to confirm that. <br /> <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[keermalec]

<blockquote><font class="small">In reply to:</font><hr /><p>The crater you linked to, in the Mars Express HRSC image, does see full sunlight, but <br />maybe the floor only sees the sun on briefly, due to the surrounding walls? <br /><p><hr /></p></p></blockquote><br />Hm, was it winter when the photo was taken? If yes, considering Mars has an axial tilt of 25° and this crater is at 70° latitude, then this crater is above the "arctic" circle, which means it gets no sun for several months.<br /><br />If the crater is 35 km wide and 2 km deep the sun will have to rise above 7° to reach the bottom. Therefore over half the martian year the bottom of the crater does not see sunlight. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[3488]

Hi Keermalec,<br /><br />Check back, you have given me something interesting to find out, so please be patient,<br />I will come back with a proper answer.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[keermalec]

Will check back for sure.<br /><br />In the meantime I have found some more info:<br /><br />And according to this article, it cannot be CO2 ice because the CO2 ice in this region has all sublimed away at the time this photo was taken. This article also says it never gets warm enough at this latitude for water ice to sublime. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[3488]

Hi Keermalec,<br /><br />This is a simulated view from the crater on: Wednesday 2nd February 2005, the date of<br />the Mars Express observation.<br /><br />The Sun was in front of Taurus, so it is very close (just before) to the Northern <br />Autumn / Fall Equinox on Mars (terrestrial analogue would be mid September).<br /><br />At noon, the Sun rose to just over 30 degrees above the southern horizon.<br /><br />So my calculations match your description well. The Sun could shine onto the base of the central <br />ice mound, but only just.<br /><br />Here is a simulated view from same location but on Thursday 11th November 2006, when <br />the Mars Reconnaisance Orbiter zoomed in with the HiRISE.<br /><br />The Sun is in Aries, so late Summer on Earth, terrestrial analogue, Late August. The Sun rose<br />to 37 degrees above the southern horizon @ noon.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[keermalec]

Cool program you got there, 3488, for situationg the sun from Mars.<br /><br />I googled for "temperatures on Mars" to determine exactly if it was possible that certain regions on Mars are permanently under 198K and sure enough, from this link it seems that latitudes above 70° North and below 70° South are permanently below 198K, unless there is a dust storm...<br /><br />This meens that unprotected ice can (and does from the ESA photo) exist in the polar regions. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[keermalec]

Even better: from this study, LIQUID water can presumably exist in Southern Utopia Planitia for 34% of the martian year! <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[gunsandrockets]

Cool link and very interesting map!

 

[3488]

How about these?<br /><br />One of the lowest places anywhere on Mars.<br /><br /> Coronae Scopulus?<br /><br />Valley within Coronae Scopulus.<br /><br />The Southern Utopia Planitia is an interesting update. Viking 2 landed too far north.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[JonClarke]

key phrase: <i>if it were present</i><br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[keermalec]

<blockquote><font class="small">In reply to:</font><hr /><p>key phrase: if it were present <p><hr /></p></p></blockquote><br />True, but water is certainly present, even if in very small quantities.<br /><br />If the atmosphere contains 0.03% water by mass, and x% of water particles attain escape velocity at 313K (highest dayside temperature in mars orbit), then x% * 0.03% * mass of the atmosphere is the amount of water being outgassed by Mars to maintain equilibrium every day.<br /><br />I don't know X as this implies working out a Maxwell–Boltzmann Distribution for water molecules at 313K, which is above me. But i do know that the average speed of water molecules at this temperature is 600 m/s and that the escape velocity from a 250 km altitude on Mars (top of the atmosphere) is 4'850 m/s. x is the percentage of water molecules which attain speeds above this. <br /><br />I suppose, but do tell me if I am wrong, that any water being outgassed in Utopia Planitia on days where it can exist in liquid state may be found in liquid state. <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>