MARS OUTCROP SOURCE OF TINY SPHERES

JPL ^ | sol 13, opportunity, mars | JPL

[djf]

I agree. The only natural occurring sphere type material I've seen is geodes, but they are nowheres near as uniform as these. I want to see another micrograph. If they all have holes in them...

[LibWhacker]

Just wild guessing here . . . Raindrops are round, formed by surface tension . . . Could these be droplets of hot ejecta from a meteor impact that froze solid in the atmosphere and then rained back down on the site?

[Ichneumon]

but the formation hits this old field-tripper's eye as lithophysae or, to use less technical terms, spherulites or mini-thundereggs.

According to several websites I've checked, thunderegg formation requires water to carry dissolved minerals into the bubble cavities. Interesting.

[Bernard Marx]

I've frequently seen them broken into halves. "Fragility" is a relative condition. Remember, this is a meteorite crater! Something smacked into the surface with a lot of force. At this point other factors that could cause movement or compaction of Mars' crust are unknowns.

[djf]

Then,they would be tektite type material. Everybody, remember the other day, they put pressure to s tie littered with this material, all all the light whitish fragments seemingly disappeared, they should try the same thing here.

If so, they are way too fragile to be tektites.

[FreedomCalls]

[RightWingAtheist]

There was also an Outer Limits episode where they found diamonds on Mars. Unfortunately, they also found bloodthirsty killer sandsharks living there.

[doodad]

This is what I am thinking, but as you can see not uniform.
http://images.google.com/imgres?imgurl=www.mineralminers.com/images/hematite/mins/hemm112.jpg&imgrefurl=http://www.mineralminers.com/html/hemspdc.stm&h=360&w=480&sz=15&tbnid=gBwGPXhNu0YJ:&tbnh=94&tbnw=125&prev=/images%3Fq%3Dbotryoidal%2Bhematite%26svnum%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26sa%3DN

[quantim]

"I'm with you wondering if the Martian gravity had some effect in all this."

It is everything about gravity.  And temperature.  My 2 cents is from a giant impact (this crater obviously) as molten rock is blasted into the vacuum (or atmosphere) it will coalesce into a sphere, harden possibly (smaller ones) and fall back to the surface and begin the surface erosion processes.  Subsequent seismic activity can account, along with liquid water, for almost any bizarre landscape geology over millennia. 

If there was significant moisture or even a body of water then many of these various spheres would crack just as a hot marble will dropped in a glass of water. 

[Darksheare]

I vaguely remember that.
But, I also have memories of several Outer Limits eps crowded into one and muddied together.
*chuckle*

[doodad]

They are not all on the same layer so more than a single event caused their formation. (If you assume it is sedimentary in nature, which a particle fall would be).

[doodad]

See my post to lib whacker #111

[djf]

Actually, the more I think abot it, something damn odd is going on. Remember the other day when they brushed them and they were all crushed. (or, mysteriously ran away under their own power).

If they were crushed that easily,how can vast numbers of them survive martian climates, windstorms in excess of 300 mph, the dust devils, etc?

If they are very fragile, the only way for them to be here in these numbers means one thing:
they are somehow being replenished.

[djf]

After taking another good look, they are definitely eroding out from the rocks.

I'm gonna go out on a limb here and say some type of coral... the first extraterrestrial fossils!

[doodad]

they are somehow being replenished.

Well, the instrument apparently pushed them into the soil which is why they "disappeared." And you are right they are being replenished. The formation is eroding the softer layers leaving the more resisitant spheres behind. I mapped the Murphy marble belt here in Ga and there was a slice of ancient ocean crust which had been squished against the marble bearing formation in a type of structure called a melange. The volcanics had metamorphosed in the less resistant surrounding sediments as balls about the size of cannonballs. You could look at a road cut and see them falling out of the weathered soils.

[Bernard Marx]

thunderegg formation requires water to carry dissolved minerals into the bubble cavities. Interesting.

There are lots of theories and I've read similar ones. I try to keep up on this stuff and as far as my research shows, no one really knows for absolute certain how they form. Water may or may not be a factor, or it may be in some situations and not others. The "tinies" I'm talking about are usually just spheres of rhyolite with no silica inside. There are many different types of formations that fall under the catch-all term "thundereggs." But if water's involved on Mars, all the better!

[R. Scott]

Bauxite ore? calcium carbonate?

[LibWhacker]

. . . all the light whitish fragments seemingly disappeared . . .

I'm still scratching my head over that one! Were they crushed to powder, or pushed under the surface (as one NASA caption claimed). Either way, it's weird as heck. If you push something under the sand here on earth, there will be evidence . . . A dimple in the surface of the sand, or something. The surrounding sand won't fill in the hole as if it were water. Yet that's what seemed to happen to "the sand" supporting at least some of those objects.

[Dan Evans]

I'm thinking that where you have spheres falling from above and hitting rock, you have pieces of spheres below the rock. Since the fall isn't that great, to me it indicates that the spheres are somewhat fragile.

In one third gravity they would have to be very fragile to be broken by a fall. But why couldn't they have been broken when the "host" rock broke apart?

[LibWhacker]

Yep, that's a great point, thanks.