The thermal cycling hypothesis for erosion has been advanced for Mars since the 1960s - before we had landed even a single mission on the surface - but personally, I’m not convinced. The effect should be ubiquitous and would apply to every clast/rock a rover can see, but just about any landscape shot shows that there are plenty of rocks without the network of cracks you’d expect. Paul Hammond is correct in pointing out that rocks preferentially fracture along planes of weakness (the direction/face where a mineral is naturally weakest), and the composition of the rocks should have a lot to do with it, but I still think that the process would be a lot further along after billions of years.

The potholes you see (…feel) in places with sub-zero winters show us exactly how good freezing/thawing water is at breaking and flaking hard surfaces, so Mars Guy isn’t wrong to point that out first in the video.

I know that the mission releases the proper calibrated images here, but only some months later, so neumast’s reply is the correct one for now.

Thanks for your detailed reply, Paul. It would definitely be worth compiling a set of NavCam images like the ones we’re talking about here. A casual review came up with this recent one, and Sol 1093 has another, so there should be a few.

Just to clarify, the very specific framing of the NavCam tile above is something I don’t remember seeing much since we landed. There are a few elements that make the shot perfect, like the ratio of rover suspension/wheels to surface, the shadows, alignment of the rover and so on. The sense of depth created by seeing parts of the rover at different heights from the camera is really important here. I realize that I’m getting into the weeds and thinking like a photographer and not a rover planner. I’m just trying to point out that this specific framing here is both informative and artistic - maybe even iconic - in a way that other regularly-planned shots don’t quite match.

I’ll see if I can compile a list in the next week or so.

I don’t want to be pedantic here in saying this: Mars experiences dust storms, rather than sand storms. That is a significant difference, because dust is light enough to stay aloft for much longer than sand, which has noticeable effects on climate. Today’s Martian atmosphere cannot loft sand very far. Keep in mind that sand storms would be much more effective at eroding rocks like the one Percy is investigating now - and doing damage to things like rovers and solar panels.

Imagery from today (sol 1084) shows that visibility is not great - parts of the Jezero rim are hazy or invisible - but it’s far from the worst we’ve seen on the planet (I’m thinking of what Opportunity saw in the great storm of '07). I would actually expect Ingenuity to survive this.

Potato-shaped??? I’d like to see Mars Guy’s figure after a few billion years…

Please. Some respect here for these two well-accreted ellipsoids with a few extra tera-tons. If you people want to swipe left on something, you can go straight to the Belt with all those charisma-free rubble piles and old boulder-faces. Sure, they’ve got the organic matter and the metals, but we’ll see who you come running back to when you remember who’s been lighting up every romantic Martian evening for all these eons…

Perseverance is deep within the ongoing Margin Unit campaign, where orbital signatures of carbonate minerals appear strongest.

Perseverance is approaching a small, ~50-m-wide impact crater that has created a natural cross-section of rock layers of the Margin unit, potentially providing new views of deeper bedrock. The team is eagerly awaiting images of the interior of this small crater, which could reveal information about the emplacement of the upper Margin Unit.

Based on orbital satellite images, rock layers near the Jezero Crater Rim are thought to be among the oldest rocks that could be explored by a rover on Mars. Therefore, the light-toned rock layers pictured here could represent much older strata than has yet been explored by Perseverance – possibly dating back to the Noachian (approximately 3.7 – 4.1 billion years ago). Exploration of these terrains could provide unprecedented insight into the climate and environmental habitability during earlier and possibly wetter periods in Mars’ history.