Journey to Mt Sharp - Part 5: Into the Valleys, Sol 706-752, Aug 1-Sep 17, 2014 Options

[Gerald]

The drill resembles more a chisel without a thread. That's not an answer to your question. But it reduces the relevance of the direction of the rotation.

[Ant103]

A comparison of the drilling site. Before and during (respectively Sol 722 & 724)

Attached thumbnail(s)

 

[djellison]

The drill resembles more a chisel without a thread. That's not an answer to your question. But it reduces the relevance of the direction of the rotation.

Yup - there's threading -but only inside the collar mechanism that pulls dust up into the CHIMRA mechanism

http://www.nasa.gov/images/content/727102m...-43_946-710.jpg
http://bestdrillingbits.com/wp-content/upl...bit_diagram.jpg

Infact - the drill doesn't really spin round like a drill at all. It's more a percussive chisel that rotates only at about 60rpm...not the hundreds and hundreds of a typical 'drill'

https://www.youtube.com/watch?v=nq9xUr4T7E8

[centsworth_II]

A comparison of the drilling site. Before and during...

Maybe there was no fracturing at all, just a movement of the plate undergoing all the vibration with the edges being revealed as the plate moves and sand settles.

[serpens]

I think you are right. In fact I would posit that the vibration of drilling resulted in the settling of dust fill in pre existing cracks around the plate perimeter and there was little if any plate displacement.

[Phil Stooke]

If you overlay the pre- and post- preload test Mastcam images you will find there was some movement even then.

PS - Damia, that's a really beautiful view in your latest image.

Phil

[Gerald]

From the tailings I'd guess, this MAHLI image should show the mini-drill"hole".
The "rock" seems to be very very soft. The drillbit got clear easily.

Edit: The rock looks like a loosely cemented sandstone with a size of about 150 - 200 μm for the larger grains.
Here a 2x magnified and sharpened crop of this MAHLI, showing some of the tailings, scale calculated from the motor count:

[jvandriel]

2 Panoramas taken on Sol 720 with the Mastcam R camera,
Images Debayered, stitched and sharpened.

Jan van Driel

[jvandriel]

and the other one.

Jan van Driel

[SFJCody]

Are these panoramas to seek out the most benign terrain for driving?

[fredk]

A postcard from Sol 720, Mastcam100

Beautiful debayering job, Ant. Could you let us in on your secrets - is that using ImageJ or Gimp?

[Ant103]

Thank you Fred and everyone

Fred, before I was using ImageJ, but I found that G'MIC Gimp plugin Bayer reconstruction worked better (less artifacts from jpeg degradations of the Bayer matrix).

[Bubbinski]

I see the sol 726 raw images have come in. The drill hole looks elongated, is it because the rock is so soft?

[elakdawalla]

When they start drilling, the first thing they do is to tap a little hole in the target without much rotation of the drill bit. It looks like they got as far as tapping the hole but quit before getting to the part where they rotate the drill bit.

[Bubbinski]

Thanks Emily. On the MAHLI images there are a lot of grayish "tailings", do they have the sample they need or are they going to try drilling elsewhere nearby?