SpecialSetOfSieves @ SpecialSetOfSieves @lemmy.world

Posts

12

Comments

4

Joined

1 yr. ago

Question(s) for Paul Hammond:
Do you keep any rock specimens, personally? Would you find vesicular basalt to be charismatic enough to earn a place as one of your pet rocks? I see that you like these "shiny" or "polished" cobbles we've been seeing all mission long... I think... but we don't often analyze them in this much detail.

AHHH the suspense! Come on relay network, send us the next ones ASAP! I know those sats are busy too, but this wait is killing me.

I really wasn't sure we'd abrade here. I mean, we skip past funky-looking darker caprock all the time (for months at a time when Ken Farley is in a hurry)! Even when the rover can physically reach it. Just look at this stuff, it's craggy and lumpy as anything... but that flattish patch they're grinding: yes.

Even with all the evidence for volcanic deposits around here, I honestly wouldn't guess what this abrasion patch might show us. Volcaniclastic rocks like tuff aren't the hardest for sure, but this stuff forms the resistant layer here. We focus a lot on sampling with this mission, understandably, but I'd love to read more about the science team's deliberations over whether we do (or don't) stop and abrade stuff. We always abrade before we take a sample, so abrasions are just as important as samples in a lot of ways...

Apologies for the word salad. Paul Hammond knows my pain.

Judging by the rocks Percy has been viewing in the last few sols, this hillside has seen quite a bit of hot/volcanic material falling from the sky, and not just from a single asteroid impact either. The geology here is captivating.

In 2004, the Mars Exploration Rover Opportunity spotted so-called, “Martian Blueberries” at Meridiani Planum, and since then, the Curiosity rover has observed spherules in the rocks of Yellowknife Bay at Gale crater. Just a few months ago, Perseverance itself also spied popcorn-like textures in sedimentary rocks exposed in the Jezero crater inlet channel, Neretva Vallis. In each of these cases, the spherules were interpreted as concretions, features that formed by interaction with groundwater circulating through pore spaces in the rock. Not all spherules form this way, however. They also form on Earth by rapid cooling of molten rock droplets formed in a volcanic eruption, for instance, or by the condensation of rock vaporized by a meteorite impact.

See also this recent Mars Guy episode.