Before and after GIF
Click to view attachment

Has there been any discussion of scooping soil from an adjacent area and using it to fill the hole?

Any soil that went into the hole would be loose, and since the the mole needs friction to dig it might defeat the purpose. They would need to push down directly on it with the bottom edge, which would be extremely close to the mole's body. Plus that would require time to plan and set up, which they don't really have at this point.

I think the main reason they are not trying to scrape up soil and fill it in is that they have no suitable tool with which to do that.

Yes they do, they have a scoop, with a sharp edge for leveling the ground for SEIS, but they did not need it for SEIS as the ground was flat enough.

Can we get Curiosity to drive over, drill a hole, and drop the mole in?

I know this was a joke, but since I'm an engineer I have to point out that an MSL drill hole is about 17mm in diameter and 4 cm deep, and the HP3 mole is 27mm in diameter, so this wouldn't work even if the sites weren't 600 km apart.

At our rate of progress to date - it would only take....210 years.

Gonna need a bigger RTG.

Sol 246 - looks like the scoop was placed very near the surface at the location of the most recent contact, but not a grain of surface material seems to have moved, so probably no actual contact. Testing positioning again?

Phil

Assuming that it is possible to do some compacting and/or filling-in of the surrounding regolith, do they then have to replace the superstructure before they can try to hammer in further? If not, then (hopefully in something less than 210 years), I suggest building a conical mound around the portion of the mole that is still above ground.

Like the other recent contributors, I'm grasping at straws here...

Apollo 13´s CO2 removal stile

Push number three? Sol 250 (Aug 10)
Looks like at lease 2 pushes in different locations during this sol. We can see some crumbling of the pit wall, but due to the late afternoon shadows we can't yet see inside the pit. But progress is progress
Click to view attachment

We can see a bit into the hole. Brightness jacked up, square-root style. There is some soil collapsed around the mole. However, I can't tell if this is progress from the previous status.

Doing something similar with the sol 243 image, I think there is certainly some extra material in the hole on sol 250.

Phil

Click to view attachment

looks a bit better on sol251
https://mars.nasa.gov/insight-raw-images/su...0000_0250M_.JPG
based on the integrity of the hole, it makes sense such a simple pressing action would not fill the hole very much further than it has already collapsed, and even so the resultant infill would be too loose and leave a derth of soil around the probe that would tend to complicate attempts at further compaction, so it would seem the approach requires additional soil followed by compressive pressing.. im sure they've already tried different approaches based on all foreseen contingencies, well see what comes up next.

There were two separate scoop contacts on sol 250, and now two more on sol 253. It looks like the strategy is to press in different locations to encourage material to slump into the hole, though it's not always apparent that anything happened. The first contact on sol 250 did result in a slump of material into the hole. Whether this is enough, or whether more material will have to be pulled in, is something we will have to wait to see.

Phil

Here is the hole after sol 253, brightened to show debris in the hole. A bit more than on sol 250, but not much more.

Phil

Click to view attachment

little scoop stomp loop (7 frame gif @4fps) sol253
Click to view attachment

Looks like we will be waiting until after conjunction for any more progress on the mole. My impression so far is that the strategy of making the wall of the pit collapse is not going to be enough, so maybe we will see the scoop pulling soil towards the hole.

Phil

Sounds like a good call Phil: Blog update from Leonard Davis: http://www.leonarddavid.com/mars-insight-mole-madness/

Mole update from DLR
https://www.dlr.de/blogs/en/all-blog-posts/...aspx/ressort-2/

Thanks for sharing that link, its incredible to consider the duricrust is being so resistant that even pressing with the blade tip didn't collapse the pit appreciably, which backs up the inference that the tiltmeter recordings support the scenario of "...the mole first lifted the SSA while at the same time penetrating slowly about 7 cm until it had hammered through the duricrust and the SSA resettled on the ground.", suggesting that pinning the mole against the wall of the pit may indeed be perhaps the best remaining option.

I guess one worry with pinning the mole with the scoop is what happens after the mole digs in completely below the surface. Then the scoop will no longer be able to provide pressure so there's a risk that the mole will stall again in loose soil or a new cavity. What about scooping/scraping soil into the hole in addition to pinning with the scoop? Is there much risk with scooping/scraping?

The risk might be that the surface is unpredictable if it's cemented, rather than loose sand or dust. The scoop might stall and then jump, or a plate of duricrust might break and shift, at an unpredictable location.

Phil

What about digging a hole farther away, in order to better understand soil properties and to get some material to file to mole hole ?

In this we are assuming that the void is due to soil properties. There is the possibility that the void was created by vibrating in place if the mole encountered a large rock similar to that exposed by InSight's exhaust.

I don't see how any amount of vibration in place could produce a void in the complete absence of adhesion between the soil particles. If there is a subsurface rock like the one pictured - too big to circumvent and too solid to punch through, then there is no path to success in this location. Transplanting the probe will have to be considered. Digging a new hole elsewhere initially as a source of loose fill (assuming that the shape of the scoop and the force it can exert allow this) might make transplantation possible as a last resort.

As a last resort in that event, there is one option that I can think of to try and extract the mole which would be extremely dangerous to the mole, but would be better than giving up completely. Something that could first be tested of coarse in the test bed to see if it could be possible to do. There are three things in our favor, We have a long arm that can Kinematically move linearly in three axis of motion, we have a 5 fingered grapple and the mole is a cylinder. The machinist in me is talking here like how a lathe chuck holds round bar stock, how about try and grab the top of the mole with the grapple with enough closing force to to grasp it and try pulling it out? The arm and grapple then could vertically position it to a new location. Once positioned above a new location, the arm could lower the mole with the tip of it just touching the surface. After this is done, the mole could start hammering with the arm feeding down with it at the same rate as the hammer cycle. Once enough of the mole is in the subsurface and not at risk of toppling over, the grapple can release slightly but still help guide it down. The grapple is on a lanyard, so really guiding it with the grapple during this step might not work well, so really just releasing it completely would be better.

The biggest issue in all of this is that delicate flex print cable, grabbing it heavily risks hitting or severing it, but if the cable could fit in the space between two fingers, could that be possible? Also since the mole is not currently vertical but tilted, grabbing it would be a challenge unless the scoop could first be used to try and tug on one side to straighten it out. If that could be done, the only obstacles would be getting around that cable with the grapple and clamping around it with enough force to hold it and not slip. Anyone know what the clamping force the grapple has? I know it uses paraffin wax actuators which obviously have allowed the grapple to lift the weight of the science instruments to the surface. In a video that I had seen, one engineer had said when it closes around a pin and the wax cools, the fingers lock around the pin which prevents any inadvertent release. How about that for thinking outside the box?

Expected to hear something on progress of the mole by now but the arm continues snoozing as if waiting for something.
Otherwise, interesting preliminary assertions on other fronts are coming out nonetheless, as Nat'l Geographic quipped "...magnetic machinations of Mars are marvelously mad"

I just wonder how far will they go before they give up. If all appears lost, will they try things as radical as that? Or backfilling the hole, pack it down, and even put the skoop on top of the probe itself to force it down? Like, how far would they take this, and what would be the minimum depth to get any usable science?

Interesting: Anyone found the abstract for this that's not behind a paywall / login?

As a spectator, I'd rather see the mole team try something risky than simply give up. But for institutional reasons this will be difficult. I guess the decision would have to be made collectively, to avoid one person's becoming the scapegoat for the failed experiment if they end up breaking the mole. Also, they would need to apply for a lot more DSN time to manage a hail-Mary final attempt, and without a high probability of success the application might not get very far. Likewise for other resources like personnel costs.

If the mole is to be written off, is there anything that can be done to further clarify what went wrong? Any way to increase the chance that a future attempt will succeed?

This is the first I've heard of a magnetometer on Insight. Which investigation is this a part of? SEIS?

The nat geo article is tough to get to... even logging in, I had to click through their frontpage and then it still said it was one of my 5 free articles that month. The gist there is: #1 the surface field is stronger than predicted from orbit, #2 there are fluctuations at local midnight that might be a sort of atmospheric tail in the solar wind, and getting MAVEN overhead at midnight is something they'll try, and #3 there is an electrically conductive layer at indeterminate depth that could be watery.

Source: https://www.jpl.nasa.gov/news/press_kits/in...sion/science/#7

Many of the Insight conference abstracts are here:

https://meetingorganizer.copernicus.org/EPS...019/orals/34053

P

Many thanks

I mentioned way upthread that there is a poor cumulative track record for the success of digging and subsurface probes on the Moon and Mars. Apollo struggled with this multiple times even given repeated opportunities and humans + problem solving present. The mechanical properties of regolith are varied and not perfectly understood. It's not clear that any particular test process will duplicate mission conditions. Existing legacy technology used for digging and boring on Earth uses mass extravagantly, and can't be adapted to this.

My own non-mechanical-engineer musing has thought about something like this: One or more strong but non-metallic spears that separate from the lander at altitude, drop point-down and impact the surface at high velocity. A spear could have non-mobile thermometers at various depths up and down its length, and transmit temperatures to the lander. If any spear survived, you would get your data.

That said, the last time something somewhat like this was attempted, it failed.

I think I mentioned this somewhere up-thread, but there are extremely high-G sensors for US bunker-buster munitions.
These are part of smart-fuses that are designed to survive penetrating several meters of reinforced concrete, detect a void and then detonate.

One idea - most landers have some sort of ballast, make that ballast out of tungsten flechettes.
Release the flechettes into the landing ellipse, then let the rover check the newly drilled holes for readings.

The worse case minimum depth is 3m. At that depth it will take a lot longer to complete the experiment.

I think that the ballast weights land a long way for the craft landing zone, that is probably why they haven't done that yet

The latest images from Homestead Hollow shows they moved the IDA (arm) closer to HP3 on sol 295, attached is a processed IDC image.
Hopefully a precursor to activity that will get the mole back in action, but there no update in the DLR mission log since August (prior to conjunction)
Click to view attachment

Arm activity places the scoop directly above the pit on sol 298. Maybe another attempt planned for compressing the regolith? There was no apparent contact with the ground observed on any of the IDC or ICC images released at the time of this post, so this looks like preparation.
Processed IDC attached
Click to view attachment

From https://www.seis-insight.eu/fr/actualites/4...symphonies-seis
(links to sound clips etc. are on that page)

SEIS's symphony of ground, air, amd metal

After its trip to the martian surface last february, InSight's seismometer
SEIS, furnished by CNES, has been listening to the red planet. This cold
desert world, whose lively geological past has given way to a profound calm,
"breathes" again, albeit in a subtle way. In its ability to detect seismic
waves from fault movement or meteoritic impacts, SEIS will permit the study of
the internal structure of mars and will provide crucial information for
interpreting the history of its formation and evolution.

Sonification

Whether terrestrial or planetary, seismology is a somewhat austere discipline.

Unlike the bounty of images returned by the satellites in orbit or the rovers
wandering the dusty and desolate surface, most of the data returned by the
seismometer every day is hard for humans to look at. Although seismic signals
can be displayed as waveforms or converted into colored spectrograms (where
each frequency is represented as a function of its power), these
representations are not intuitively comprehensible. There does however exist
one technique which, though it sacrifices a bit in realism, can make the data a
little more engaging and convivial, sonification.

Given the frequencies involved, the data returned by SEIS cannot be heard by
the human ear. Additionally the signals are much too weak to be heard in their
original form. However by amplifying the data and speeding it up it can be
rendered audible. They aren't real sounds such as a microphone would record,
but the result is nevertheless interesting and intriguing.

The rumble of mars quakes

Since being put into service at the start of the year, InSight's SEIS has
registered about 100 events, about 20 of which have been interpreted as mars
quakes. The first one took place on sol 128, 7th april 2019. Two more quakes
more powerful than the first were detected on sol 173 (22 may) and then sol 235
(25 july) with magnitudes respectively 3.7 and 3.3. Intensively studied by a
team of planetary seismologists, they have revealed very interesting things
about the martian crust.

While waiting for the publication of these first scientific results, the
signals recorded on sols 173 and 235 by the high-sensitivity VBB pendulums were
sonified by researchers at the Institut de Physique du Globe de Paris and made
available as sound files by JPL, the NASA center responsible for the mission.
These extraterrestrial quakes, which shook the ground of a planet hundreds of
millions of kilometers from earth, sound like muffled rumblings.

(see page for links to sound files)

Several sources of external noise

With its extreme sensitivity SEIS doesn't just hear the movements of the ground
but rather all of the noise in its environment, including its own.

The most common noise source is meteorological. InSight's landing site on
Elysium Planitia is particularly windy. Aside from wind gusts, dust devils
abound and occasionally rustle the lander. Although this atmospheric
turbulence, mainly active during the day, must be removed from the seismic
data, scientists can use it to study the near subsurface.

Other strange or amusing sounds can be uncovered by the golden ear that is
SEIS. This is particularly the case with the robotic arm which makes a sort of
loud squeaking sound.

Even stranger, some clicking sounds, called "dinks and donks" by the science
team, can be heard mainly in the evening when the wind dies down. They come
from the seismometer's own internal workings. Inside the instrument many parts
expand and contract with the daily temperature changes. Although the
seismometer has many levels of very effective thermal protection (the vacuum
vessel, the RWEB thermal sheild, the WTS bell), it can't be entirely isolated
from the martian environment. The result are unavoidable ticking sounds, like
after a car's engine has been shut off and it cools down, which get recorded by
the seismometer. Other very suble noises are caused by electrical
interference.

(sound file)

So when they're sonified, the signals recorded by SEIS are transformed into a
special type of concert: a symphony of ground, air, amd metal, of which an
example can be heard below. Assembled by NASA from data provided by the team
in charge of the seismometer, the clip shows, with help from images from the
IDC camera and a spectrogram, the sounds generated by movement of the robotic
arm, wind activity, as well as the rumbling of the seismometer's internals.

(youtube clip)

seems so, 9/29 entry on the leonarddavid site not much new news just "...Bottom line: Will they succeed in covering up and filling in this hole in one?"

Also handy live translation for SEIS page to help view those links in readable context

On A Mission Podcast : InSight’s Insights (October 2,2019)

Discussions with:-

Tom Hoffman: Project Manager
Bruce Banerdt: Lead Scientist
Sue Smrekar: Deputy Project Scientist
Matt Golombek: Landing Site Lead

Media Page including links and full transcript: Link
MP3 Podcast - duration ~46 minutes: Link

Yikes. If they can have the arm push on the mole, it works for a couple strokes, and then they'd have to do it all again... painstaking if it comes to that.

Also mentioned is that it's at close to the limit of the arm's reach, so dumping soil right into the hole isn't feasible. They'd have to dig, pile, and bulldoze it over there, if I interpret things right.

Not sure if mentioned already, but wondering if getting some stones into the hole might work better instead of soil alone, by rolling them into it from nearby outcrop. When the mole starts hammering it could possibly wedge the stones in tighter between the mole and the wall of the hole, giving the mole more purchase power then from soil alone. But I'm sure they've thought of everything already.

Lots of great info in the NASA article PaulH51 posted. Thanks!
It sounds like the arm is too extended to 'pull' soil in from behind it, but i don't see any reason why the back of the bucket couldn't be used to push soil into it from in front of the hole instead.

On that note, as Walfy mentions above, I also have a hunch that larger pebbles would provide better wedging properties than sand, as i would suspect it would tend to disrupt void formation, and it looks like there is plenty of suitable material within scoop or scrape range.
I am only roughly guessing at the rate things are going, if all else fails, that the supposed Hail Mary: "Let's just push on the back and see what happens, and see if we can get it to move forward." since the arm cant really 'push' but only hold position, is going to take a lot of in vitro testing and perhaps software updates to support command sequences and prevent complications, and so probably wouldn't be attempted for another year or more.

The newest images give me the impression they are testing positioning for a direct push on the mole, not leading up to a new surface contact.

Phil

Tweet from NASAInsight
"My heat probe recovery efforts continue…
I’m going to use my scoop to push sideways on the mole, “pinning” it against the soil wall. This may help it get more traction to start digging again. More details: http://go.nasa.gov/2OhxNFz"