On the Road Again - volume 4 - Page 4

"how they can differentiate between ejecta (Martian)or meteoric (astroidal) origin"

Gabbros are present in rocky planets, satellites and major asteroids so we won't know with the tolls we have. There may be compositional, accessory mineral or textural differences, but at this point we don't know.

Another puzzle piece, and we need to step back and see what the overall picture looks like.

--Bill

Is that a rift of some sort crossing the ripple? Some indication of tectonic activity?

Er, Barsoomer, that's a rover track on the left hand side of the sol 2111 L1 5x1 panorama, better seen on the right side of this sol 2058 R0 5x1 panorama.

sol 2116 ( Jan 6, 2010 ) MI pan of Peck Bay Rat hole on Marquette Island:

with links to 3D pairs.

I will colorize this image when the pancam images are downlinked.

I am a little positionally challenged here. Was this grind over a previous brushing? If so a Hortonheardawho visual magic brushed/ground comparison would be useful.

This is the cleanest rat we have seen from Opportunity for a long time.

First they brushed, then did the grind without the post-grind brushing, then brushed it.

Need to go back and look at the grind that was done on Bounce for comparison.

--Bill

serpens, I was planning on doing this with the colorized versions - but here you go.

sol 2110-2116 MI panorama animation:

It looks like the sol 2116 RAT activity was just a brush of the sol 2110 grind. Perhaps there is an interest in the rock "paste" as well as the rock?

Reply 50 by Barsoomer

Opportunity thrashes nearby ripple. Rover vandalism!

What I see middle,upper,pieces for "crust that have fallen from rover wheels,crust broken trough by rover weight,?
Can ever thing excluding rocks be "crust"?

This is left side middle of the two highest peaks on right side of Image.Thickness of crust? Repeated on the far right peak.
How are these held together?
They look uniform in both "dig in peaks"and
are probably crust that has fallen from wheel? Or?

In a way, the "chips" from the grind are rather like a streak test, so perhaps they wanted to evaluate the spectral signature of the chips. Or perhaps it was related to the examination of the wear in the RAT abrasion wheels/stones/whatever.

Joe, thanks for the reminder about the crust. I have a few thoughts about that too. It looks like there may be hollows or at least loosely packed soil in the ripples under the crust. Depending on how impervious the crust is, I wonder if some moisture could be retained under the seal formed by the crust. Also the pressure might be a little higher there because of the overlying weight, perhaps enough to stabilize liquid water when the temperature rises above freezing.

Thank you Hortonheardawho. But the most interesting animation comparison would be the pre grind brush compared to the post grind, brushed rathole. Correlation of surface features to the ratted surface (if any correlation exists) could give some information on crystal/inclusion shapes and vein depth.

OK, serpens, here is the sol 2070 brush / sol 2116 brush after RAT MI pan animation. The MIs were shot from different positions and the autostitch program introduced other perspective distortions, but it you watch the animation long enough you can "see" the changes.

And here is the sol 2117 3D color by horticolor™ of Marquette.

sol 2070-2116 colorized MI pan animation pf Peck Bay on Marquette Island block after first brush and after RAT and second brush:

OK, this is quite interesting!

First there is the usual coating of red dust, then a coating of white material that required the RAT grind to remove and then a darker interior rock with a variery of colorful inclusions?

Mayhaps the white stuff is, um, salt?

Hi all,

After reading your blog for many years now, I thought I would "drop by" and say hello and thank you for all your support in all these years of exploration with Spirit and Opportunity (even those who think that I am a narrow-minded biologist - I am actually a geologist!). But that does not matter. Everybody is entitled to an opinion. I just hope that you are enjoying the ride as much as we are and ready for the next with MSL. Now, going back to dig out Spirit . Happy New Year to all! Nathalie Cabrol

OK, this is quite interesting!

First there is the usual coating of red dust, then a coating of white material that required the RAT grind to remove and then a darker interior rock with a variery of colorful inclusions?

Mayhaps the white stuff is, um, salt?
============================================
Why Not Hort? after all its Mars.Wrong color for iron,gotta be salt.
======================================
someone tell me the keyboard keys to stop/
start animation?
Gratefull
Joe in Texas

Er, Joe Smith, for Flickr GIF animations, you have to click on the picture link and then view the original size.

Hort

Your latest colourized anim is perhaps the very best colourization you have done. Practically perfect alignment and colour. Those white chains that remained on the ratted surface seem a bit anomalous to me. The rat did'nt move them and they have a shape that is counter intuitive for salts.

Hi Nathalie Cabrol;

Thanks for posting here and expressing your appreciation of the blog. I think we are all rooting for some miracle to happen with spirit and for Oppy to find some who's. All the best for your endeavours in the new year.

Winston

Brilliant Hortonheardawho. An order of magnitude better than my clumsy efforts.

The white effect is not salt but is a result of the miniscule size of the rat dust particles which enables the true colour of the minerals to be seen. The streak test effect that Bill refers to in his reply 69. I feel that pyroxenes, possibly bronzite, and olivine are the prime candidates in the context of MI. Both orthorhombic with white streaks.

Nathalie A. Cabrol, Thanks very much for your reply 74. I've never known how near or far we may be from real scientists on this blog. It's great to hear that there is some connection.

Hi Nathalie a nice surprise that you came by, we never really know who visits here but never post.

Good luck getting Spirit free and a Happy New Year to you too.