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Today's closeup image of sand grains in the Columbia Hills

Posted: Mon Oct 24, 2005 5:10 pm
by Aqua
As proposed in an earlier comment, we see erosion at every scale on Mars

Golf balls with indentations fly much better and further than without. Less rounded sand granules may be differentiated in a similar fashion?

The 'flight characteristics' of sand and dust particles may be enhanced by their shapes? 'Floating' them along at whatever isobar and/or combined pressure, temperature and electrostatic field gradient is defined?

The larger surface area of less rounded particles would tend to absorb more thermal energy and electrostatic charge than would a more rounded particle of similar mass?

Mars gravity is 38% of Earth's.

Awful large for sand grains

Posted: Mon Oct 24, 2005 9:51 pm
by aichip
It only takes a moment to see that the image, at 512 pixels across and 3 cm total span, is showing us a lot of particles that are jreally stretching the limit for sand. In fact, those grains are mostly classified as fine gravel - being 2-4 mm in diameter.

The most coarse sand is only up to 2mm in diameter, and many of these particles are much larger than that. Simple math shows that at 3 cm over 512 pixels, just over 17 pixels is a millimeter. So anything over 35 pixels in span, in any axis, is fine gravel and not sand.

Why is this important? Because we often accept without question what we are told, but in this case, it is clearly not so. We can do the math and prove that. And, at this size and taking the atmospheric drag into account, it would take a wind of hundreds of miles per hour to get these particles airborne. The fastest measured wind speed on Mars' surface was 74 mph by Viking.

Posted: Tue Oct 25, 2005 12:49 pm
by craterchains
Yes the "shape" of the particles would have an effect on their abilities to become air born, and to stay aloft longer. Their shapes resemble that of crushed rock gravel, or possibly fractured by impacts, or explosions.

Norval

Posted: Thu Oct 27, 2005 1:45 am
by S. Bilderback
If they moved, their edges would be much rounder.

Mars dust storm:

http://antwrp.gsfc.nasa.gov/apod/ap990809.html

dust grains

Posted: Thu Oct 27, 2005 1:52 am
by ta152h0
perhaps the winds go around the mountains and nothing moves when on top of the hill. It would be interesting to have measured wind velocity at that height

Posted: Thu Oct 27, 2005 2:09 am
by S. Bilderback
The atmosphere is also thinner at the higher elevations, it's simple particle separation as would be seen along a shore line, the smaller particles are dispersed farther than larger ones. These have moved much less keeping the edges more pristine.

Posted: Fri Oct 28, 2005 4:21 pm
by Aqua
The problem with modeling 'weather' on Mars is that there is a tendancy to 'compare' it to the water cycle weather patterns, here on Earth.

Again, Mars gravity is 38% that of Earth.

Extreme temperature gradients exist between the surface and immediately above the surface.

Mars seems covered with finely reduced dust which when held in suspension or in a state of liquifaction, in effect/for all practical purposes, becomes a fluid, with characteristics somewhat like terrestial waters.

One MAJOR ingredient not usually taken into consideration, are the effects of solar induced tribo-electric energy throughout the Martian atmos. column.

Q: What elements make up those 'sand' particles? And, given the Martian conditions, what are the properties of those elements?

Dust devils seem to follow electro magnetically induced vortices, which appear as elongated spirals. That is to say, think of the shape of a 'bedspring'... the narrow end touching ground... spiraling on down. INCOMING!... or is that OUTGOING! ?

Sprites come to mind .. near surface Martian sprites that is.... as weather generators... and collumn reducer.. and elemental bonding agent?

Posted: Fri Oct 28, 2005 4:49 pm
by Aqua
There is a remote but interesting possibility, that the 'Canali' that Lovell and others saw... WERE in fact actual features, that is to say.. Supercell Dust Devils in planetary dust storm conditions, may have 'swept up' the Martian surface.. revealing darker underlying materials?

Subsequent storms recoated/covered those patterns... making those observations useless?

Posted: Mon Oct 31, 2005 5:01 pm
by Aqua
NASA Science Webpage story about Tribo-electric charge on Mars:
http://science.nasa.gov/headlines/y2005 ... ckling.htm

NASA Science chats up solar electric weather on Mars:
http://science.nasa.gov/headlines/y2005 ... devils.htm

Bottom line? Evidence is mounting for rethinking massive erosion patterns on Mars surface.

Stratified particulates suspended in the atmos. collumn act as a fluidic stubstance with pressure and temperature gradients reducing lofted materials by composition, mass and conductive properties. What is the surface temperature during planetwide dust storms? What variations in the entire collumn? What tribo-electric charges are present in the collumn? Does Mars generate 'Sprites'? or similar? Is 'lightning' common during dust storms?

During dust storms, does the surface temperature climb high enough to release frozen CO2? or H2O? or ? from the soils? What changes in atmospheric conductivity would result? cohesion factors? ion bonding factors?

Posted: Mon Oct 31, 2005 9:05 pm
by craterchains
Yes, Aqua, many questions. Some day we will have the answers. :)
While some may be examining those potentials you present, others are saying that the water and winds appear to have done the deed.

We have our own erosion patterns to examine and see the similarities. These markings on Mars are easily recognized by those that study the effects of water erosion here on earth. The present known facts about Mars is that it's water is frozen under a thick debris cover in many areas. Prior to the flooding we know that it was heavily bombarded and the surface tore and ripped to pieces. Much of these areas have been "sanitized" by the flooding after all those craters formed. 8)

Norval

Posted: Tue Nov 01, 2005 12:32 am
by Aqua
"We have our own erosion patterns to examine and see the similarities. These markings on Mars are easily recognized by those that study the effects of water erosion here on earth."

Again.. is that 'water erosion' or solids ACTING like liquids? I think its a mix of the two.

In which case... we may have grossly underestimated surface winds (read: particulates in suspension or liquifaction) and transportation of materials thereby...

A favorite saying: "He or she who goes there, knows there!"

I'd really, really, really like to see what the Viking Landers are looking like today. That is... if there's anything left?

Yeah... 'In a perfect whirled', maybe we'd get Burt Ratan to make a rocket/robot that goes on out an grabs one of the old KH-11 spy satellites, refurbishes it, and sends it on out to Mars orbit for a little ol close up 'look see'!? Be nice to have a big dia. mirror on orbit... say 60"?

robotic visitation

Posted: Tue Nov 01, 2005 3:38 am
by ta152h0
That would be a neat event- one robot visiting another robot. How close are the two nearest robots to each other??

Posted: Tue Nov 01, 2005 5:16 pm
by Aqua
It would be difficult, at best, getting the intelligence agencies to release enough technical info. to see whether or not anything could be salvaged and recycled from any of their decommisioned platforms?

Would it prove economical to use old, 'on-orbit' mirrors, solar panels, motors, sheilding, and/or ? Most of the heavy-weight flights were flown on Titan IV's... i.e. BIG guns!

Some of those platforms have been on-orbit for many years. Visiting them might answer a few questions as to why certain equip. went 'off-line' and how materials reacted to the space environment during that period.

Another 'X' prize might be awarded to the first to provide on-orbit robotic salvage and repair services? Space salvage rights anyone?

The Chinese will probably be the first to attempt this?

What gets me, is that we did not design the shuttle's external fuel tank to be taken on up into orbit. How many would we have up by now? What kinds of industry(s) might be attempted in those spaces?

Posted: Tue Nov 01, 2005 6:02 pm
by BMAONE23
Ă…qua wrote:
What gets me, is that we did not design the shuttle's external fuel tank to be taken on up into orbit. How many would we have up by now? What kinds of industry(s) might be attempted in those spaces?
If they did keep a tank, they could use it at the ISS to store and remove garbage. This could then be sent on a one way trip to the sun for easy incineration.

Posted: Tue Nov 01, 2005 6:14 pm
by Aqua
I was thinking more along the lines of low gravity metals manufacturing platform?

Pharmacuetical manufacturing platform?

Semiconductor manufacturing platform?

Or using the tanks at lunar orbit?

Spraying ice on the external surface to a thickness of several feet would make those tanks good radiation shelters for long duration missions? Spray em, then cover em with aluminized mylar....?

Posted: Tue Nov 01, 2005 8:28 pm
by BMAONE23
Perhaps they could use a certain thickness of transparent aluminum for the windows for even better protection.

Transparent Aluminum? That is the molecule that Scotty used to barter the 6" thick plexiglass in Star Trek 4.

http://www.af.mil/news/story.asp?id=123012131

Well Science mimics art.

robot visiting each other

Posted: Tue Nov 01, 2005 10:39 pm
by ta152h0
I was thinking more in terms of the mobile robots sitting on MARS surface to visit each other. Nice answer though :D

Posted: Wed Nov 02, 2005 5:07 pm
by Aqua
My thought was to spray the outside with water vapour, then cover it to protect it from Sol rads.

Trick'd be to use a 'Bassard-like' collectors to gather useful matter, i.e. Hydrogen and Oxygen, on-orbit. (nuclear pwr'd Bussards?) Make rad. sheilding as you go along? Robots 'rig' the shelter, collect and spray water ice shielding, mount and maintain external equipment?

Deployable parabolic Fresnel lenses to melt ice and heat steam powered rockets, anyone? Some fun, eh? AND they'd be easy to see? in the 'boost' phase anyway.. cometlike?