Dammit Insight! You just had two big jobs to do on Mars and you're failing at one of those The heat probe aboard NASA’s InSight lander is having trouble digging into the surface of Mars due to “unusual soil conditions,” the space agency announced on Sunday. Designed to burrow up to five meters below Martian ground, the device, affectionately named “the mole”, has only managed to descend 35 centimeters since it began …
Based on the soil seen around the other landers and rovers, the soil has an extremely deep layer of Duricrust (low friction, high cohesion soil). In the other places where the rovers moved around and sampled soil, the duricrust was seen to be no more than about 2-5cm deep. Here we're looking at over 20cm. So unusual for Mars? Who knows. But unusual based on the evidence of previous missions. Definitely.
And the Mole is self propelling - it's basically a jackhammer, so No you cant put an auger bit on it.
Oh well if the team can get it down to about 40cm, then it should be able to go forward with out any further problem (once fully past the duricrust and regular soil conditions return). But yeah this is a set back. But thats Science, doing something in the unknown, under conditions no one's ever done them before, and then overcoming the problems that develop.
Good luck little Mole...
(from an ex-HP³ Team member)
“But thats Science, doing something in the unknown, under conditions no one's ever done them before, and then overcoming the problems that develop.”
Well said, been there, done that, got the paper published to prove it. It can be quite a thrilling thing to see or realise something nobody has ever seen or realised before. But that is scientific discovery for you. I’ve chalked up a few in my time. I’m a Developmental Biologist though so my research subjects were much closer to home. But much still remains unknown down in this gravity well.
Thanks for this insight. I guess I was being somewhat flippant all around; an auger style tool would obviously be a significantly different design and would need something to work against (but then, the current mole seems to, too).
It's pretty ambitious to aim for 5m into soil of such unknown composition. Heck, we have enough trouble getting a clear run digging holes for planting trees around here.
Anyway, I wish it well!
No problem, just thought I'd clear up details. :)
We did actually see something similar to this happen during initial Earth testing under extremely low pressure conditions. Turns out taking the very small amount of air cushioning out of the interior of the Mole in low pressure conditions caused the internal spring mechanism to give a much larger reverse force then anyone expected (I mean we're not talking a huge volume of air inside the Mole even on Earth, but that was enough to provide some damping). We made changes to the Mole to correct this and it worked fine in later low pressure testing.
What we naturally couldnt test and which may be having an effect in concert with the dastardly soil conditions, is the low gravity combined with the low pressure.
Anyway, what has been seen is that with grip on the side of the Mole (from the arm on the lander pushing the Mole against the side of the hole), the Mole works perfectly. Going down until it disappeared almost completely into the soil. The arm was then moved away (out of fear that it might damage the tether), and pressed on the top of the soil surface near the hole to try and provide some force in that way, but that that wasnt enough to stop the Mole hitting reverse. There's going to be a lot of head scratching going on now to try and work out how to stop that happening again... :)
You could put an auger on it with sloped interface and a ratchet so that it turned it slightly with each whack and didn't unscrew itself. Saves putting a drive motor on it and it just being a drill, best of both worlds?
Oh and some mole repellant just in case.
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It sounds very much like drilling through the plaster in our house. My dad built the house and on my grandmother's side we're descended from many generations of plasterers. When I finally get through to good quality 1950/60's brick it's softer.
Unfortunately not. It was never designed to be relocated, and the arm on the lander only has a scoop on the end, so no way to grip it. The arm does have a special magnetic coupling on it (which it used to put the Seismometer and the mole on the martian surface), but the coupling for this on the Mole was on its support structure, not on the Mole itself, so unfortunately that cant be used either.
We'll just have to see if they can get it back down in this location.
they wouldn't have had this problem is they'd just followed the plans and fitted it with a giant spiral drill bit.
So there you are, watching dust devils and basking in the distant sunlight, and suddenly another one of those funny machines falls out of the sky. You're long used to them running about your surface (it tickles). But THIS one, without even flowers or a cheap dinner, starts a cylindrical penetrator moving vigorously in and out, trying to work it deep inside you. How rude! You're not THAT kind of planet, no matter what Mercury says about you. The ingress is rejected and blocked, and you sulk for a few months.
So once again, humans have built a machine that mirrors themselves. Send it somewhere new and it starts trying to f**k the first place it can shove its tool.
Actually they can get some pretty amazing science out of the pair of them. By listening to the moles hammering, the Seismometer readings can be used to get a really detailed look at the local sub-surface conditions to quite a depth (sorry cant remember the values now).
Plus the Mole, once its on its way down, is pretty damn fast, so you're only talking a short time where the Mole's hammering is eclipsing the Seismometers search for marsquakes...
I salute the efforts of NASA's engineers to get this to work, but how much easier would it be with people who could survey the site, choose the best location, and adapt the drilling gear for the conditions?
Unmanned probes are great for passive observations, but if you want to interact with an unknown environment to this degree, you need a lot more flexibility and brainpower on the ground.
Insight is becoming a great argument against those boring bastards who think manned spaceflight is a waste of time and money.
Given the weight of the wetware and its support systems, think of the kit you could put up if you had the luxury of sending all that mass. You could certainly send up a fully equipped electric mini-JCB, another piece of kit to put it upright if it falls over, and a load of cameras on little rovers.
The limitation isn't the lack of people. Its the lack of maximum payload.
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