Crossing the Dunes at Murray Buttes, Sites 54-62, Sols 1353-1659, May 28 2016-Apr 6 2017 Options

[PaulH51]

On the way to 'Stop 4': Workspace 1639 L-MastCam, MS-ICE raw colour

Sadly no mission update issued by USGS for the weekend activities.

[PaulH51]

1639 focus merged MAHLI. Not sure which of Curiosity's 2 MAHLI targets planned for 1639 this is (“Greenvale Cove” or “Holmes Hole”)?

It features a small dark rock that appears to have been crushed by Curiosity's front right wheel at the end of its drive to 'Stop 3' on 1636 when it drove onto a mudstone outcrop and then turned in place (to scuff the sand?).

The damage has revealed an interesting interior of small voids. Not sure if these could be related to igneous processes? trapped gas etc?

Are the nearest (now extinct) volcano's that were the likely source of the basaltic sands of the Bagnold Dunes) in range of Gale for a small rock like the one here? Or maybe ejecta from a violent impact event that melted the host rock? Or maybe something completely different. Looking forward to some speculation before JPL comments. There also appears to be a small amount of damage to the edge of the mudstone outcrop, and the fresh fractures (if they are fresh) reveal an interior just a little lighter than the exterior

Added a scale bar based on the motor focus count, also added a border scale with each unit representing 1mm, in retrospect I feel the border scale is a little OTT, thoughts?

Uploaded to Flickr as wanted the members to see the original detail rather than reducing the quality to meet the upload limits.

[jvandriel]

The Navcam L view on Sol 1639.

Jan van Driel

[Gerald]

The damage has revealed an interesting interior of small voids. Not sure if these could be related to igneous processes? trapped gas etc?
...

The visual similarity to scoria is indeed surprising.
I'm wondering whether it's related in some way to the nearby Hematite Ridge, either as a remnant of an overlying eroded layer, including clastic dykes, or as impact ejecta.
There is also some remote similarity to vesicular pillow lava. But I don't see how this would occur as isolated lapilli, except may be as a volcanic bomp plunging into water.

[PaulH51]

....Thank you Gerald, for sharing your thoughts on that damaged rock

1641 MAHLI Wheel-Check animation reveals another Hitchhiker

[serpens]

The visual similarity to scoria is indeed surprising.

From the smooth surface it appears to be an armoured vesicular lappilli.

[PaulH51]

Drive: Midnight Planets reported 'Curiosity moved approximately 27.6m S (177º) on Sol 1642' Link
L-NavCam pano from 21 images very roughly assembled in MS ICE, too big for page upload, so small preview and link. It may help pin down the location until a proper version is posted by Jan or Damia


Full size link on Imgur

[Floyd]

"1641 MAHLI Wheel-Check animation reveals another Hitchhiker"

Maybe the rock will pound out some of the dents and smooth some rough edges

[Art Martin]

"1641 MAHLI Wheel-Check animation reveals another Hitchhiker"

Maybe the rock will pound out some of the dents and smooth some rough edges

I'm thinking we have an example of the first extra-terrestrial rock tumbler. We could end up with a lovely polished Mars Rock.

[Phil Stooke]

Phil checking in from LPSC in sunny Houston (well, humid The Woodlands really). Here is Paul's panorama in circular form, and it gives a good position for a map update.

Phil

[jvandriel]

The Navcam L view on Sol 1642.

Jan van Driel

[HSchirmer]

I'm thinking we have an example of the first extra-terrestrial rock tumbler. We could end up with a lovely polished Mars Rock.

Eh, a tangent to that, something had occurred to me quite a while ago...

If the grousers/treads had standard sized sieve inserts, or perhaps a set of calibrated grooves,
then each wheel revolution would give you information about the mix of sorted particle sizes.

Imagine a sequence of grooves or chines, etched onto the grousers, or the flat area between grousers.
It's basically series of wider and wider "sieves" which catch the finest particles, and let
the coarser ones fall to the next sorting.


- 80 mesh

-- 60 mesh

--- 50 mesh

---- 40 mesh

----- 30 mesh


What if each wheel revolution automatically sorted the soil particles by size?

[PaulH51]

Drive on 1643: L-NavCam partial pano assembled in MS ICE
Midnight Planets reports as 'Curiosity moved approximately 36.8m ENE (74º) on Sol 1643' Link

[PaulH51]

1641 MastCam mosaic with RMI inset of an outcrop close to the rover. 10 cm Scale bar using AlgorimancerPG on NavCam stereo pairs.


1024 version Link
Full res version Link

[PaulH51]

Breaks in Raised Tread on Curiosity Wheel:

A routine check of the aluminum wheels on NASA's Curiosity Mars rover has found two small breaks on the rover's left middle wheel-the latest sign of wear and tear as the rover continues its journey, now approaching the 10-mile (16 kilometer) mark. The mission's first and second breaks in raised treads, called grousers, appeared in a March 19 image check of the wheels, documenting that these breaks occurred after the last check, on Jan. 27.

Full report

ADMIN NOTE: Dedicated thread re Curiosity wheel issues here.