[X] My Assistant

[djellison]

Look at the MI campaign on this puppy It's got to be a 4 x 4 frame MI mosaic

http://qt.exploratorium.edu:16080/mars/spi...cam/2005-04-28/

Doug

[stevo]

I'm curious about the "blue kryptonite". False color aside, its morphology is clearly different from the outcrop it's lying on (smoother for a start, implying newer? harder?) and it has odd swirly patterns on top. Can anyone suggest an origin? volcanic ejecta? meteorite fragment ?

And besides, if you look at earlier photos of the same rock, it appears to have a pretzel glued to one end ...

http://qt.exploratorium.edu/mars/spirit/pa...HEP2280L7M1.JPG

[Guest_Edward Schmitz_*]

I'm curious about the "blue kryptonite".  False color aside, its morphology is clearly different from the outcrop it's lying on (smoother for a start, implying newer? harder?) and it has odd swirly patterns on top.  Can anyone suggest an origin? volcanic ejecta? meteorite fragment ?

And besides, if you look at earlier photos of the same rock, it appears to have a pretzel glued to one end ...

http://qt.exploratorium.edu/mars/spirit/pa...HEP2280L7M1.JPG

When I saw this rock, I thought it looked odd, too. It took me a while to put my finger on it. There is not sediment around it. With all the dust and sand blowing around and the protected area under the rock, it should quickly gather dust around the base. This hasn't been there very long.

Does anybody have context images?

I'll bet it broke loose from an outcrop that is just out of frame. Not very long ago.

[Tman]

http://qt.exploratorium.edu/mars/spirit/pa...HEP2280L7M1.JPG

When I saw this rock, I thought it looked odd, too.  It took me a while to put my finger on it.  There is not sediment around it.  With all the dust and sand blowing around and the protected area under the rock, it should quickly gather dust around the base.  This hasn't been there very long. 

Does anybody have context images?

I'll bet it broke loose from an outcrop that is just out of frame.  Not very long ago.

I guess too this rock became ejected by an impact event in the Gusev volcanic floor. It's a similar like those on the plain. Regarding the time and dust, I would say "not long ago" too, but it lies on a naked rock, maybe therefore without dust.

Methuselah east: (900KB) http://www.greuti.ch/spirit/spirit_navcam_sol477.jpg

[dvandorn]

http://qt.exploratorium.edu/mars/spirit/pa...HEP2280L7M1.JPG

When I saw this rock, I thought it looked odd, too.  It took me a while to put my finger on it.  There is not sediment around it.  With all the dust and sand blowing around and the protected area under the rock, it should quickly gather dust around the base.  This hasn't been there very long. 

Does anybody have context images?

I'll bet it broke loose from an outcrop that is just out of frame.  Not very long ago.

I guess too this rock became ejected by an impact event in the Gusev volcanic floor. It's a similar like those on the plain. Regarding the time and dust, I would say "not long ago" too, but it lies on a naked rock, maybe therefore without dust.

Methuselah east: (900KB) http://www.greuti.ch/spirit/spirit_navcam_sol477.jpg

Remember, it gets windy up in the hills. I can imagine a sequence of events where a piece of basalt gets lobbed on top of a much softer piece of sandstone and the winds strip the sandstone down to a flat, "floor-tile" appearance (sweeping the eroded dust away) and leaving the denser basalt far less eroded. Now, in such a case, you have to postulate changing wind directions to explain the lack of a "shadow" of non-deflated dust, but it's not hard to believe that winds would vary enough to accomplish the job. Especially over the thousands (maybe millions) of years that basalt has been sitting there, the sandstone underneath it slowly blowing away in the wind...

It can be hard to apply common-sense "gut feelings" about erosion processes to aeolian weathering, especially in such a thin atmosphere, since it takes so *very* long for that thin air to erode the softer rocks down flat. Over the very long time that it takes to erode the sandstone flat, prevailing wind directions can change a lot, especially in a hilly region where we *know* atmospheric vortices are common.

-the other Doug