Not Geddy, Alex and Neil?

Too bad the Mars microphone is not there - I can just hear the "Hello- Hello- Hello- Hello!" when I see that pic....

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.

Sol479 true color PanCam images, top context based on Sol477 NavCam stitch by jvandriel (see http://www.unmannedspaceflight.com/index.p...dpost&p=10176):

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

Presumably they'll eventually run out of names for rocks, a bit like IP Addresses and WWW domain names...

...I'm still waiting for Wilson, Betty and Kepple (they'll be mobile rocks like in Death Valley, but lubricated by fine sand rather than mud, and the one in the middle will be the best looking!).

(Now watch the minds boggle!)

Nice.

From Vapor Trails:

"...endlessly rocking... endlessly rocking..."

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

http://qt.exploratorium.edu/mars/spirit/pa...B2P2417L5M1.JPG


Looks like some Martians left some Patio slabs laying around......

Either the odd rock or the underlying layers caught the science team's eye. On sol 514 they snapped it again, from closer up, in a full filter sequence.
Here it is, in false color: