Sliding into 'Home Plate North', Heading for Spirit's 2008 Winter Retreat Options

[Stu]

Get yer fingers in that dirt...

[Tesheiner]

Looking at it from this angle it does look hazardous, the drifts appear to extend onto a relatively flat step.
http://qt.exploratorium.edu/mars/spirit/na...9DP1926R0M1.JPG
this slope looks nice though
http://qt.exploratorium.edu/mars/spirit/na...9DP1926R0M1.JPG

I thought it would be nice to see Spirit's current location from another perspective.
Here's a picture combining the view from the current site (as of sol 1400) on top of HP and another one from the bottom, taken on sol 767. I tried to identify some rocks on both mosaics (1, 2, 3, and the group numbered 4) and some parts (A, B, and C) of the northern slope. The slope A is the one right in front of the rover.


OT: A Mars bar will be the prize for anyone able to find the old tracks between points 3 and 4. I couldn't.

[Tesheiner]

On another topic, but still related to winter haven, here's an article from the OSU (Ohio State University).

Software Helps Mars Rovers Find Winter Havens

The accompanied picture is mostly centered on the path to Von Braun. I would really like to find a similar one for HP north.

[TheChemist]

Thanks Tesh, this comparison helps a lot.
Slope A looks nice and navigable, but I am cautious about the lower wheels if Spirit is parked there.
Will there be enough rock underneath them ?
If the lower wheels sink in sand, getting out in spring might be difficult.

Not that we have any other options with winter approaching fast, of course ...

[john_s]

OT: A Mars bar will be the prize for anyone able to find the old tracks between points 3 and 4. I couldn't.

The complete obliteration of the old tracks here is remarkable- it's rather humbling that our mark on this corner of Mars was so short-lived. But wouldn't it be nice if it was a sign that winds tend to be funnelled through this trough, and that we might therefore hope for some cleaning here?

[djellison]

I was thinking exactly the same thing - there's a bit of evidence of winds on this site - the little dune at the bottom, the exposed rocks....Spirit might get some good treatment here...fingers crossed

Doug

[peter59]

I hope that Spirit's tilt at WH3 ( about 30 degrees) may help to clean solar panels by faint wind.

[mhoward]

Spirit might get some good treatment here...fingers crossed

Amen to that. I wonder if there is also a temperature advantage in parking over a nice large exposed rock face here, as opposed to parking over sand-covered rock somewhere else.

[jvandriel]

North Side of Home Plate.

The panoramic view taken on Sol 1398 with the R0 Navcam.

jvandriel

[Stu]

Small colour section...

[Julius]

The high silica content detected by Spirit seems to be the result of geyser or fumarole activity in the past:thats the official interpretation of this finding.

I've read in some papers discussing atmospheric evolution on Mars as to a process where CO2 interacting with CASIO3 on the surface would also produce SIO2 and CACO3.However since martian carbonates have not been detected up to now,scientists have been reluctant to give such process much importance.

Could the present absence of carbonates justify to rule out this process as the source of SI02 in Gusev!?What other evidence would favour geyser/fumarole activity rather than CASI03 as a source for the high silica content of home plate soil?

[Stu]

Bit more...

[climber]

It's gona be though to find exactely the rigth place with the rigth angle. I'm happy we're already where we are because I guess it'll take several sols before weels stop. Fortunately angle will compensate for solar power decay.

[dburt]

Could the present absence of carbonates justify to rule out this process as the source of SI02 in Gusev!?What other evidence would favour geyser/fumarole activity rather than CASI03 as a source for the high silica content of home plate soil?

CaSiO3 is the mineral wollastonite, which forms via contact metamorphism of siliceous limestones, not via crystallization of basaltic lavas. Not surprisingly, spectral data show no such mineral on Mars (AFAIK), although I'm not sure anyone is looking very hard for it - it wouldn't be expected, without limestones. The high silica content of the soil in "silica valley" (stratigraphically beneath the Home Plate rocks, apparently - therefore older than Home Plate proper and not necessarily a part of it) remains a mystery. High-silica alteration is typical of silica-rich volcanic systems, such as Yellowstone Park, and is rare or absent in low-silica basaltic systems, such as Hawaii. The Home Plate system is presumed to be volcanic based mainly on its basaltic composition. No volcano is evident, and no lava flows either. If the silica-rich soils result from alteration by a hot spring or fumarolic system, that system could just as easily be related to impact cratering and impact melting as to volcanism. All you need is a local buried heat source interacting with groundwater (including melted ice). Boiling of the hot water (which would happen at quite low temperatures on Mars) releases acids which alter (leach the basic oxides such as MgO and CaO out of) the rock, leaving silica (commonly with alumina). In hot water, silica can also be dissolved and reprecipitated at a distance. Alteration of glasses is faster and easier than alteration of crystalline lavas. Hope this sheds some light.

-- HDP Don

[jamescanvin]

Looking for a nice spot...



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