With an idealized tilt angle of ~53° between the pointing of the mole and the surface normal, a 5 m teather would still be long enough to reach a nominal 3 m depth required to accomplish the primary science objective (take the triangle defined by the Pythagorean triple 3³+4²=5²).
Within those constraints, this would presumably maximize the friction between the mole and the soil beneath induced by the weight of the mole.
So, this approach would probably feasible without an entirely new proposal.

How could the tilt of the mole could be controlled? I'm not aware of any way to do this.

First, it's required that the mole bounces back and partially out of the ground like it happened once already.
If we assume that this will happen a second time, I see two approaches:
- A risky one, use the scoop to tilt the mole. Ensure that the force doesn't damage the mole.
- A less risky, but more time-consuming approach: First dig a ramp with the scoop, then tilt the mole, cover it with soil, use the scoop to initially push onto the soil cover when hammering. Alternatively use the scoop to prevent the mole from bouncing like demonstrated already.

If the risky approach fails and the mole ends up horizontally on the surface, the scoop will be needed to move the mole, to dig a ramp, to move the mole to the ramp, and to cover it with soil.

If the mole remains stuck and neither forward nor backward motion is possible by hammering, we'll have a less trivial issue. I doubt that pulling at the teather would be an option. Scooping deep enough to free the mole will be a challenge. Scooping just to the mole might be feasible. This might change the behaviour of the mole. But it also bears a significant risk to be a dead-end.

The vigorous interventions you describe, Gerald, are not supported by the level of interactivity and power levels on the lander. This would be the kind of thing someone might do with one of those arcade games where you pull the toy out with a crane, but Mars is 6 light minutes away and getting farther. A small action with the arm produces no feedback regarding the result until a photo would be taken and sent back to Earth. If the arm is in the way of the photo, it would need to be moved, then moved back. We might need for an orbiter to revolve into position to receive the photo, then transmit it to Earth when DSN bandwidth is available. And the power levels on the lander are at a premium, so they were looking at a 14-day cycle between interventions, 7 days in the better case.

This is not like building a model ship. It's like trying to get a trained dog to build a model ship while you yell commands through a windowless door.

Unfortunately, just because something is physically possible, even with the Earth-based test model, does not mean it can be practically replicated on Mars.
If this was the first 90 sols of the mission in terms of power generation, and there were no other spacecraft requiring data relay and DSN time, (and we already knew the soil properties ahead of time!), things might be different. I know from OSIRIS-REx's drama with the sample collection that there are extenuating circumstances where emergency DSN time can be given, but HP3 is not like that. Add of course, February will be very busy again on the red planet.
If the January hammering does not work, it may be time to throw in the towel. Mars hasn't chalked up a win in a few years, after all....

I mostly agree with what you say. But if the addressed science is considered relevant and required to be done, then we have to compare those time and expenses with the time and expenses needed for designing, proposing, building, testing, landing and operating a backup mission.
I'd presume that DSN will communicate with the orbiters, and a few commands more each week or so to inSight won't make a big difference for the total traffic with Mars.
All I can do is sketching some options. Making the decisions is someone else's job.

I don't know how close Insight is to end-of-life threats, but with power in short supply, and with other Mars missions having failed critically when power ran out, efforts with the mole draw from another important budget – the diminishing power on the lander – as well as human labor and operations expense. The seismometer is working well and it would be a shame to have that part of the mission terminate earlier than it had to because of failed efforts to get the mole going.

I hope that we'll get a clearing event and maybe the lander could work for another entire martian year, but this is northern winter now, and winter is the killer of solar-powered surface elements.

Arm activity above the mole on Sol 734 (December 20. 2020)
Animated GIF
Click to view attachment

I would argue this is the only budget that actually matters. The others are negotiable. This one is not.

Power generation by the solar arrays is described in this paper.
Ancillary sc data are provided here.
The latest currently available data set is of Sol 569. Data are only partially recorded.
Here an attempt to plot a diagram:
Click to view attachment
The maximum current within the data set is roughly 0.1 A.
The portion I don't yet understand is the factor of 11,000 Vh in Figure 4 of the above paper.
If we would just use that factor, we would get about 1 kWh for Sol 569. But the factor may depend on the duration of the daily sunshine.
Unfortunately, I don't have access to more recent telemetry.

More information about InSight power management is provided in this paper.

The power requirement of SEIS is described in this paper.
The heaters seem to consume up to 1.5 W. The instrument usually requires about 5.9 W, see subsection 4.1.9, but can be up to 11.83 W, see Table 5.
So, 250 Wh per day should be sufficient to operate SEIS continuously.

In addition, the main system, and communication requires power. I didn't yet find out how much.
And there will be some power loss by the batteries.

HP³ is described in this paper. See Table 1 for information about a 4h hammering activity. If I summed up correctly, it's 367 Wh.

Thus far my attempt of today to provide some, but a still incomplete, basis for further considerations.

I think we can be confident that the team has thought about additional activities that could be tried to recover some of the HP3 science, and they are in a much better position than we are to evaluate what's possible and what's not.

That is correct - about 1000 W-hr per Sol. (Note that the length of day hardly varies at the equator)
I'm glad the paper was of interest.
Ralph

Thanks a lot, Ralph!
Your paper helps significantly to understand the InSight probe, and how to use housekeeping data to retrieve additional science!

The tether has a substantial tear in it, about 20% across. May not be usable anymore.

I'm guessing you're referring to this? Let's hope that it's just a mark left by the scoop rather than a tear!
Click to view attachment

During the previous hammering effort it was unclear whether the mole made any progress. So, a mark together with a well-defined and flat surface of the soil would be helpful to assess progress during the next hammering effort.
There is some diffuse darkish material next to the well-defined dark line. So, I take the optimistic point of view that the dark line is dust, too:
Click to view attachment
Why else should they have placed the scoop at exactly this position? With days or even weeks of planning for each step, it's rather unlikely that anything is done by accident.

There is a new paper by Mariah Baker (Smithsonian Inst.) et al. in JGR-Planets about changes at the InSight landing site (following on from an earlier paper by Charalambous et al. in GRL). The changes include dust devil tracks. I don't recall whether illustrations of this had been posted here before so I made a new one based on work in that paper.

The image shows two Context Camera images from sols 228 and 232, plus a representation of the difference between them (VERY contrast-stretched). Looking at the raw images, you see no obvious changes but the difference image reveals two dark streaks on the edge of Homestead Hollow. They are dust devil tracks and they can be correlated with tracks in HiRISE images and with data from the meteorology instrument. Note these were made from the JPL raw images page, not the PDS images which would be better.

Any pair of images a few sols apart with similar lighting can be compared in this way.

Phil

Click to view attachment

The results of the 2020 Senior Review and NASA's response have been posted

Response

Report


Some highlights from NASA's response:

InSight Extended Mission
- InSight is approved for a two-year extended mission, running from January 2021 through December 2022.
- The extended mission will focus on producing a long-duration, high quality seismic dataset. Continued operation of the InSight weather station, and accelerated burial of InSight’s seismic tether using the spacecraft’s Instrument Deployment Arm (IDA), will contribute to acquiring this seismic dataset at the highest quality possible.
- The EM will not prioritize continued deployment of the mole. Some work on the mole deployment may continue, but only to the extent that downward progress is demonstrated in the near term and other mission science or engineering goals are not affected.

What are the 'mechanical sequences' to dislodge dust from Insight's solar panels mentioned in the response? It wouldn't be using the arm to somehow brush dust off with the scoop, would it? That seems a rather delicate (and power-hungry) procedure!

'High' option does mention regolith studies / trenching / burial of the seismometer tether... though it's not clear what the tradeoffs are in the power budget.

Not clear to me whether funding is medium or high.

The scoop would not scrape the panels to remove dust - it's hard to imagine a more scary concept. Much more likely would be a series of taps on the panels to loosen dust, allowing the wind to move it. I am surprised, given MER experience, that the frequent wind gusts and vortices detected by the lander have not cleaned the panels.

Phil

Yeah, tapping the sides and waiting for a good gust seems more logical to me. But the trouble is, where are the gusts?

I am not surprised. In 2016 Dennis Reiss and I noted that the dust devil track formation rate at Elysium is an order of magnitude less than at Gusev and estimated
"a solar panel clearing recurrence interval estimate of ∼11 Mars years "
https://ui.adsabs.harvard.edu/abs/2016Icar......315R/abstract

It may be that stronger prevailing winds give you more vortices, but suppress the largest, most intense vortices that do the lifting.

Thanks. It's good to have that perspective. I was reading the papers on changes at the site and assumed more activity than there apparently is.

Phil

We just had another round of hammering. I don't see any sign of movement on the tether.

Phil

https://www.jpl.nasa.gov/news/nasa-extends-...ience-missions/

Seems to imply that burying the seismometer tether is a priority. So we ought to see a trench or two if that's the case. I wonder what side of the pinning mass makes sense? Only the far side?
No bloglike posts @ the SEIS site: https://www.seis-insight.eu/fr/actualites

well this is sad but not unexpected
https://twitter.com/NASAInSight/status/1349760462854909957

last time they tried that it didn't work any better than the mole
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/...tion?id=DEEPSP2

Ah bummer the mole did not work.
Good news though for the extended mission.

RIP Mole! We cheered for your success through 759 sols but alast, the dirt didn't cooperate!
Don't think we have time to change Rosalind Franklin to include a mole but maybe we can piggyback the experiment onto whatever is going to the 2024 opportunity.

Always disappointing when a new technique or technology doesn't really pan out, but it's a certainty that a great deal was learned regardless. This is in fact largely how we learn over time.

Kudos and great appreciation to the team for their valiant, tireless efforts. Thank you.

The InSight PDS was updated earlier this month. I went through the mission managers reports (MMR) from that update and extracted the reported energy production capability ('Whr/sol') and the atmospheric tau values and added the new data to a table with a selection of selected earlier values.
We can see the falling energy production caused by accumulated dust on the solar arrays and the increasing atmospheric tau.
The MMR's contain an interesting insight into the activities of the the team as they juggled with problems, the energy demand vs energy production etc. It would have been nice to see more extracts released to the public rather than having to wait for the PDS, but it is what it is.
Click to view attachment Click to view attachment

The HP3 instrument logbook has been updated today by Tilman Spohn. (February 4, 2021)

LINK

It contains some interesting information about upcoming papers and is well worth the read.

Here's a couple of extracts...

In other and maybe better news:

https://agupubs.onlinelibrary.wiley.com/doi...29/2020JE006382

This paper describes a recent impact only 40 km from InSight in the spring of 2019, seen by HiRISE. It's not clear if it was detected by InSight but it was very small.

Phil

Posts about impactors/penetrators moved here.

New Release (February 12, 2021)
InSight Is Meeting the Challenge of Winter on Dusty Mars.
It talks about the steps it will take to conserve power etc.
It also talks about this 'long shot' later this week
Link to full news release

Animated GIF: Pulsing the solar array motors that unfurled each panel after landing in a bold attempt to try and disturb the dust and see if the wind blows it away. Sol 789 IDC camera
Click to view attachment

I wonder in retrospect whether whether the Opportunity Meridiani Planum landing site might have been a better destination for Insight. There would have been guaranteed cleaning winds at Meridiani Planum and deployment of the heat probe would most likely have worked. It would be the obvious destination for an Insight 2 mission.

Would something like HP3 (even redesigned) be able to go through the bedrock that lies beneath the sand at Meridiani Planum, however? It was soft enough to Opportunity's RAT, but the mole is quite a different piece of hardware....

https://mars.nasa.gov/insight/timeline/prel...site-selection/ describes the landing site selection process, which was almost entirely focused on landing site safety, elevation, power, and the need for ~5m of regolith rather than potential hard rock surfaces. I see no evidence that the possibility of cleaning events was considered, if we even have enough data to do that reliably. Elysium was settled on fairly quickly ("Several workshops took place in 2013, 2014 and 2015, to evaluate 22 candidate landing ellipses and then four finalists. All 22 of those sites are in Elysium, which is one of only three areas on Mars that meet two of InSight's needs.")

See also https://spiral.imperial.ac.uk/bitstream/100...C321_Author.pdf especially figure 2.

Hopefully we will learn soon if InSight's Seismometer picked up any of Perseverance's landing hardware striking the surface.

https://twitter.com/BenFernando2/status/1362743836095766530

Insight will present at the upcoming LPSC. Some findings which caught my eye:
1/ Both the seismic and radio science show a large liquid metal core probably made of iron and sulfur.
2/ Crustal thickness at landing location has been constrained and the crustal density has come out on the low side, which could mean significant porosity. It seems to me that you could hide an ocean's worth of water in the crust if their numbers are accurate.
3/ There is definitely a seasonal component to earthquake activity, which seems to be linked to solar illumination.
4/No impact signals have been detected.

Mars has a core / It’s liquid, metal, and large / Seismic waves did tell us.

Crust results

Seasonality

Thanks for putting those together, Don. It's nice how we've gotten hard information on the interiors Jupiter, Saturn, and Mars within a few years.

These results also segue well into the MIM mission, which will considerably address the crustal porosity / crustal ice issue and a pretty distinct pathway from the one that led from "follow the water" into Mars sample return.

I'm curious how the seasonal seismic activity might correlate with the methane release cycle. It seems like we might have some crunchiness that begins with phase change and expansion or contraction of portions of the crust.

Besides the lost science from the heat probe measurements, I still mourn the failure of Phoenix to get a sample of subsurface ice into analysis. There might be something to be learned about a (slow) H2O cycle from measuring the isotopes in that ice. There's room for a followup mission that could address both of these, and both involve digging. MIM might identify the right place to do that.

Hi'

A tweet that leaves us hungry

Jonathan O’Callaghan @Astro_Jonny 20H

Statement from NASA InSight team on whether they detected seismic waves from Perseverance landing on Mars:

"InSight acquired high-resolution data from its seismometer, pressure sensor, and wind sensor during the time interval bracketing Perseverance's entry, descent and..."

2 days - 2 scoops!
Preparations for SEIS tether burial?

Click to view attachment Click to view attachment

Looks like it. I saw only one scoop a few hours ago .

Hot off the press

Someone shared this with me after I posted here: from Twitter after the 1st scoop (roughly translated from French)

Tweet

The second trench, on sol 803, was made with three passes of the scoop. The first trench used only one.

Phil

Seems we may have a timeline for the first 'dump' on the tether Twitter