Post-Solstice at Home Plate North Options

[ustrax]

I would like you guys, our resident geologists to drop some of your educated words on this image (original image has been replaced):


-What's your take on the kind of process that may have lead to the formation of a landscape like this?
-There are two splat-like features, near the images' equator, one on the left another on the right, what might these be?

Thanks for thinking about it!

[briv1016]

Is Exploratorium backed-up again? They don't have any Bonestell images after sol 1671, even though the tracking site says several additional sections have been downlinked. It corresponds to the Bonestell chart at the very bottom of the tracking data page if that makes any sense.

[charborob]

I would like you guys, our resident geologists to drop some of your educated words on this image (original image has been replaced):

What is the scale of the main image. Is it at the same scale as the Columbia Hills image beside it?

My guess would be that the small knobs (including the one in the red square) are made of more resistant rock that was left over after a period of erosion.

[Phil Stooke]

Rui, normally for a reliable interpretation, you would need to indicate the scale and also show the context of the image - where is it, what's around it? That makes a big difference to a geological interpretation.

I would guess that the area is an old deposit of some kind that is being eroded away, leaving all these little hills as erosional remnants, and that the features you highlight are exhumed impact craters. But it's only a guess. At this resolution it's not really possible to say they are like Home Plate, and they look more like hollows than 'plates' even if one side has an outer scarp - I'd explain that as part of the layer beibng stripped away.

Phil

[alan]

Is Exploratorium backed-up again? They don't have any Bonestell images after sol 1671, even though the tracking site says several additional sections have been downlinked. It corresponds to the Bonestell chart at the very bottom of the tracking data page if that makes any sense.

Spirit has been downloading thumbnails only of the Bonestell pan. Guessing here, downloading just thumbnails saves enough energy for Spirit to image an extra position in the panorama per working sol. This will allow the panorama to be finished earlier so Spirit can move from its current position. The remaining images can be downloaded later.

[ustrax]

What is the scale of the main image. Is it at the same scale as the Columbia Hills image beside it?

My guess would be that the small knobs (including the one in the red square) are made of more resistant rock that was left over after a period of erosion.

charborob, yes the scale is the same for both images.
Found a possible analogue from HiRISE:
PSP_008778_1685

The explanation given is that...there is not an explanation yet, only guesses, like yours...

"But how did the rocks form, and why did they erode onto mounds? It could have been lava or impact ejecta or fluvial sediments, perhaps altered and indurated by groundwater. The mounds could be due to how it was deposited like hummocky impact ejecta or how it was indurated. In other words, we haven't solved the mystery!"

EDITED: Phil, your answer arrived while I was writing, yes you are right, it is better to show the whole picture...
Here you have it!
The area I've cropped is located south of Thira.

[tty]

The "splat-like" features look like they might be melt-sheets from under old craters that have been eroded away.

[ngunn]

Aah - your bigger image shows that your two splat features have a much bigger cousin to the north, not far below the south rim of Thira. I would agree that something has caused the impact craters of a certain age in this region to have floors that are cemented in some way and thus erosion resistant. I wouldn't like to guess whether the cementing process is melting per se or something else.

[ustrax]

There seems to be some related information at THEMIS website:

"Lobes of a smooth material appear to have flowed, perhaps as water-rich sediments or molten lava, across an older, knobby landscape. The older surface is spotted by its pits, knobs, buttes, and mesas. The knobs may have been eroded by winds into fluted shapes called yardangs that trend northwest-southeast."

"The material (south of the Columbia Hills) partly resembles the rough, knobby terrain located on the southeast floor of Gusev. If it has the same origin, then here THEMIS may be looking through a "window" opened by erosion that gives a view down to the older knobby material that is better exposed to the east."
I presume this knobby material is the one we're talking about?

[ustrax]

I've tried to had some perspective to the area (nothing that accurate...):

But it changed my point of view about some features, for instance, the oversized Home Plate (03) seems from this angle to be another mesa-like as others surrounding it, the splat like feature to the left (01) looks like the mentioned cemented crater floor, the one to right (04)...don't what what to think of it, seems to be higher than its surroundings, is this consistent with an old crater floor (EDITED: Now looking better it looks like there's a wall to the right that could be a remnant of a crater...)?
Another feature caught my attention (02), it appears to my eyes as some sort of cone but it is probably just a optical illusion...


EDITED: It wouldn't hurt asking SS if an HiRISE image of this area is planned...
"We currently have all the HiRISE images we need to plan Spirit's operations for the coming martian year."

Why?! Why?!

Huumm..."for the current martian year"?...Huumm...

[alan]

Spirit imaging has been limited mainly to taking images of the sky recently. Could the storm near the Phoenix site be affecting power levels?

[briv1016]

Two new updates:

sol 1690-1694, October 03-08, 2008: Spirit's Memory Is Getting Full
http://marsrovers.jpl.nasa.gov/mission/sta...ll.html#sol1690

sol 1695-1701, October 09-15, 2008: Getting Ready to Make the Next Move
http://marsrovers.jpl.nasa.gov/mission/sta...ll.html#sol1695



Of note:

Instead of sending data only every fourth day, Spirit will begin relaying data every day to NASA's Odyssey orbiter for transmission to Earth.

[Tesheiner]

... and also:

Spirit has finished the 360-degree, full-color view of its winter surroundings, known as the "Bonestell panorama," and acquired extra frames at super resolution to enhance details in the imagery.

[tedstryk]

YES!!!! Now to get it on the ground

[Astro0]

Did anyone notice that Spirit's IDD is now stowed.
It's been off the hook for a long time...now that the Bonestall pan is done, maybe it's time for her to get moving as well!
Any news...anyone?