Big error on the graphic in that article, though; the Viking landers were nuclear-powered, not solar.

Well spotted

Neat... TQVM

Still dusty on ICC, but coolness above: https://mars.nasa.gov/insight/multimedia/ra...mission=insight

Is the ICC cover still on, then?

No, its off. Think they need to send up a tech with a lens cloth to clean that lens.

As noted, it's off. The cover didn't work very well, apparently.

Turns out that very wide-field fisheyes like this one can be more susceptible than narrower-field optics to dust contamination, somewhat paradoxically.

I think the wind is already starting to clean the lens. Dust after the cover came off is easily seen removed over the coarse of 33 minutes! Looks like we landed in a very windy location.

Click to view attachment

No, the circular outline is gone - dust must have sneaked in under the cover, though not too much and we can hope it will blow off.

EDIT - didn't see there was an extra page of posts! Oops.


Phil

Nice work James
Also from sol 4
Arm / Scoop movement prior to full deployment
Click to view attachment

It looks like my descent thrusters blew dust under the cover. Sorry. Hopefully wind will clear the lens. Twelve sets of 300 N (68 lbf) thrusters pulsing at 10 Hz creates a lot of dynamics. Also it looks like the one footpad visible in the photo sank 75 mm (3") or so into the surface. Certainly different than Phoenix (which makes sense since PHX landed on frozen soil).

Propguy,

I think we will deal. If it weren't for the descent thrusters, the camera would have a heck of alot more dust on it...embedded in the subsurface.

Tried some debanding on one of the new MarCO-B images, taken during the approach phase. Distance was about 18,000 km. If Phobos was within the FOV, it was lost in the compression/noise.

Click to view attachment

Another from the departure phase, taken from a distance of 17,500 km.

Click to view attachment

Strange, looking at the animation I don't really see much correlation between dust after the cover opens and visible dust while it was closed. Maybe flipping the cover open caused dust to fly off it and static electricity made some land back on the lens? Esp. when looking at the sky, I don't see much correlation at all between before and after opening. Obvious dust particles that fell off by the third image aren't present in the first one, as far as I can tell.

Well, it beats the alternative, dosn't it? It must have been quite loud upon landing. Given the compression of the soil and using the acceleration on impact it should be possible to assess the compactness of the soil. That would be interesting to see if the landing location still fits the expectations. I'm sure this will be used when evaluating where to drill.

Paolo

Real curious now to see just how much dust might've been blown away from the lander. There might be some shallow depressions around the thruster areas as well.

Latest raw images showing the arm getting it's first workout.

Would the 'hand' on the arm be at all useful for measuring the soil properties? After the instruments are safely placed, can it reach down far enough to directly touch the surface, perhaps make a small indention/trench?

Good point. Or maybe there was so much dust caked around the cover that we had a large cloud when it opened and some settled back on the lens.

Or, maybe dust wasn't deposited after the opening, but was on the lens before opening (ie sneaked under the cover during landing) and just moved due to wind after opening. Given the low correlation that seems less likely.

Of course.
"... InSight's robotic arm also has a bucket with a capacity of roughly 500 g of soil. However, this bucket is not intended for massive excavation works; its main role is to prepare the ground as well as possible before setting the instruments down. It allows engineers to shift a stone that is in the way, flatten a little mound in an otherwise optimal deployment sector, or simply check the nature of the ground."
https://www.seis-insight.eu/en/public-2/the...ida-robotic-arm

Im confused.

Is the Protective cap on the camera stuck or not?

No; it came off just fine. There just seems to have been dust underneath it somehow. It's not a big issue; and hopefully the wind will blow much of it away (same hopes as for Opportunity; windy season is upon us!)

I also wonder. Since PHX was able to erode some of the frozen soil underneath the lander, I fully suspect we moved lots of regolith. What would confirm would be a similar shot as PHX's underneath view PHX underneath photo, but not sure if we can get such a shot with the IDC. On PHX the imager was at the end of the arm, thus it could be moved to view underneath. On InSight this same shot may not get down enough to see underneath. Landed ops team is way to busy for me to bug them with that question. I will ask once they have fully deployed and finished the workspace survey with the IDC. Sure would love to see some portion of my prop system.

I was wondering why they even had a bucket, ty for that.

I always wondered why MSL rovers aren't equipped with a second arm with a scoop. It would allow much deeper samples, and the additional weight is not that restrictive.

Uh, what? How much do you think arms weigh?

The original MSL design did have two arms, one for sampling and one for contact science, but that got descoped pretty quickly.

Curiosity's arm is 67kg before you add 33kg of hardware on the end of it
See http://esmats.eu/esmatspapers/pastpapers/p...011/billing.pdf

That's pretty darn restrictive.

It's more than 1/3rd the weight of an entire MER rover.

A bit more on the use of the arm for digging etc. and imaging under the lander, in resonse to questions posted here.

Recent papers in Space Science Reviews discuss this at length, especially the second one listed here.


Trebi-Ollennu, A., et al. "InSight Mars lander robotics instrument deployment system." Space Science Reviews 214.5 (2018): 93.

says that physical properties experiments can include indentation, collapse of trench walls, and scraped and excavated dump piles.


Golombek, M., et al. "Geology and physical properties investigations by the InSight lander." Space Science Reviews 214.5 (2018): 84.


Says the IDA can make soil piles of different sizes and shapes to be monitored with the cameras, and press into the ground for bearing strength tests.

Says that the IDC will image the footpads, the area under the lander and the surroundings, so the effects of surface modifications can be studied including depressions made by the thrusters.


Phil

With respect to the dust cover effectiveness. Here's some potentially useful context from Curiosity (I have no information on the InSight covers specifically)

Because the HazCams were a build to print of MER, they had already been qualification tested in a no-dust cover configuration when the risk of dirty HazCams was identified as requiring mitigation. As a result, the dust covers were not allowed to actually touch the lens assembly of the HazCam (to a avoid driving forces into the lens assembly that the camera was not qualified for). So it was accepted going in that they did not make a perfect seal. The cover hardware created a tortuous path that would require any dust to make 180 and 90 degree turns before ending up on the lens.

The dust cover implementation was a balance of not doing anything that would hurt the camera, against having the best cover possible. Lots of discussions and working with the camera team to arrive at something everyone was satisfied with.

Since InSight re-used a spare HazCam, the same 'no touch' requirement may have been imposed on this dust cover. It's possible that the dust and engine exhaust flow environment created by the lander engines is different than a rover under a skycrane, which allowed more dust to get around the cover onto the glass.

My impression (based on everything I've read online) is that the current view will be completely OK for the uses of this camera. Dust on Curiosity's HazCams was more of a concern in terms of meeting mission requirements for drive distances - using the NavCams as backup hazard avoidance makes driving much slower.

Edit: I also think if you look at the Sol 0 picture with the covers on, and the picture right before the covers deploy on Sol 4 - there is a lot of motion of the larger dust on the cover within that time. So there seems to be a lot of wind moving dust around.

The dust on the ICC lens makes me wonder how dusty the Phoenix MARDI would have been had we ever managed to get a post-landing image out of it. Unfortunately there was a sequence glitch in the one attempt that was made, and PHX died before we could try again.

Moment of well-meaning pedantry here: Weight and mass have been mentioned several times and there's that factor of 2.64 difference between Earth and Mars, as well as the distinction between weight (in, eg, Newtons) and mass (kg). For any given object, its mass, weight on Earth, and weight on Mars are three different numbers. I'm not sure that anyone has made any mistakes in the posts above, but there's a lot of potential confusion here.

If you say that something weighs X kilograms, you really mean that it has a mass of X kilograms. I've never heard anyone in aerospace try to use some other verb than weigh in this context. Using "mass" as a verb ala Heinlein has never caught on.

Units of force are a different matter and in my experience that's where the confusion comes in.

As it is, the Insight lander is heavier than Phoenix, using the same landing jets, maybe Propguy can inform us how much more margin is in the lander for future heavier missions ?

10 kg more landed mass from what I can tell (360 kg for InSight). From what I know of the design I don't think there's a lot more mass margin. All 12 engines at full thrust produces about 3600 newtons which is about 2.6x more than needed to hover (if I did that right), but they don't run all 12 engines at full thrust and there's the rocket equation to think of.

I did a little something on the last ICC image. Yet dusty but I hope it'll get better in the next few weeks

In equirectangular projection, I think we can have a clearer view of a part of the landing site. Especially that the horizon seems to be a little bit "curvy".

https://mars.nasa.gov/insight-raw-images/su...0000_0545M_.PNG

This image from the IDC camera is more obscured than from the other cameras. Is the dust cover still on for this one? Is the lens cloudy?

Note the rainbow-like artifact on the left side of the image, and a bright disc-like artifact near the center.

Having the Sun in the corner of the frame often does bad things...

There are only two cameras, ICC and IDC. This is an image with the sun near the FOV. I assumed they moved the arm and this is the sky.

I'm not sure if the IDC had a cover (website says there is one, but I'm not sure if that's true) or if it's been removed.

https://www.hou.usra.edu/meetings/lpsc2018/pdf/2764.pdf

Great work! The equirectangular projection really helps to characterize the landing site. Definitely looks like it lander close to a good sized impact crater with ejecta around the crater rim.

Phil-o-vision, 3x vertical, of Ant's reprojection:
Click to view attachment

That is truly awesome work.

Click to view attachment

Mars....

Does anyone have Figure 2 & Figure 3 from that PDF in larger format? They would all be nice to have, especially 2c for sizing pebbles etc near the lander

The IDC moves. That range data would only be valid for that pose, pointed at that terrain in the test bed.

You could get rough pebble sizes from Fig 3, knowing the sizes of SEIS and the cable, and assuming level ground and lander in test bed and on Mars.

IDC is having a cover, as this image seems to show. I guess…

Click to view attachment

I cleaned up all the fisheye 'lens cover' images and then the 'cover removed' images and put them in a gif

Click to view attachment

observations and impressions:
* the 'grayed out section' in the lower left was to get rid of a 'residual arm shadow' (that moved between images) and made the ground to left look like a rock(!)
* the 'big rock' has a very circular pattern on top (multiple?) that looks to these aging eyes that it was cleaned off by a blast from a propulsion nozzle
* there appears to an engine blast pattern to the left of the big rock
* there appears to be 'straight lines' leading up to the right side landing pad, left to right, at an angle that parallels the outboard strut ... blast patterns or skid marks(?)
* the whole left side of the image appears to be 'cleaned out' of pebbles and small rocks, as opposed the right side of the image (blast effect? or just plain old luck?)

as always, your mileage may vary...

Cheers!

That's how I've interpreted it when hardware is discussed. The sentence that caught my eye was "InSight's robotic arm also has a bucket with a capacity of roughly 500 g of soil." Since soil isn't hardware, it seemed ambiguous to me whether that indicated soil that would weigh 500 g on Earth or whether the arm can lift 500 g of soil, which on Mars will be more like 1250 g (if it were weighed on Earth). [It's moreover ambiguous whether weight or volume is the actual bottleneck.]

I guess to be consistent, the mass is what one should use for samples, too.

Because 'weight' is ambiguous - might refer to Earth or Mars - the planet has to be specified whenever it is used. If it's not specified, assume mass is intended.

Phil

Mass is a constant. Weight is a locational variable.