As The Drive to Duck Bay comes to a close. I think it's time to start discussing the Possible Entry Points, and what will Opportunity discover when she finally drives into Duck Bay???

To me it's been an amazing 3 1/2 years that Oppy has been exploring this area of mars from Eagle Crater to now Victoria Crater. It's also amazing how this little rover is entering it's 3rd crater in it's exploration of Mars and to me this current stop will be it's biggest scientific investigation so far in it's journey and exploration.

So starting with this new topic. I think it's time to talk about The Inner Works of Duck Bay

I think they will have Opp enter at the midpoint of the bay (which looks like the shallowest slope), and head toward the cliff to the North.

I think that we will see layers of salts in the cliff as far down as we can see.

If we have to drive close to the cliffs, which will be, I guess, one of the objectives, we'll have to take care of the lighting, i.e. the time of the sol we'll have to take pictures for the best profit. Unlike Endurance were we stayed South of the crater, we'll benefit of "side views" shot with much more possibilities to have shadows that will also give very nice pictures.

I can't see how the rover could enter the Bay by it's midpoint. The dunes/ripples (see images from sol 951/952) would prevent that.
My take is by either one of the edges. The right one (looking into the bay) looks to have better ground but I think the left one, near Cabo Verde, has the most interesting rocks namely Verde's wall.
And thinking on lighting/shadows, the left side is also the best because at this time of the (mars) year the sun is on the south so the rover would be always illuminated.

What else but the fossils of ducks in Duck Bay.....he he he.

I hate to be a pessimist , but I believe not much of scientific interest will be found inside the crater. From afar we can already see that the lower layers are just lots of thick, ancient, sand-dunes. The upper layers have already been studied at Endurance, etc. I don't see us finding anything much of real interest that we didn't already see in Endurance. Other than some cool views from inside the crater, I even wonder if it is worth the risk of going in. Maybe instead we should just head for the long treck south-east.

On the other hand, I have high hopes that my pessimism doesn't pan out...

I hope layers can be found that match up with those found in Endurance,
so that the other -- non-Endurance -- layers can be put into context.

I think that's mostly what we can hope for at this point. Regarding the layers, there are layers of rock strata, and layers of rock alteration related to the paleo-water-table, and who knows what else. Back in Endurance they saw what was called the Whatanga contact, which appeared to be a line defined by textural changes in the rocks. It was thought to be the upper position of an ancient water table, iirc.

I don't expect that we'll see any new lithologies, but I think it will be interesting if they find the bathtub ring, or rings.

A geologist never meets exposed strata he or she doesn't like. Each foot of descent into Victoria will represent what? -- 100,000 years of Martian history? -- 1,000,000 years? -- 10,000,000 years? So even if the strata is uniform from top to bottom, that tells you a lot. But more than likely Opportunity's instruments will be able to detect some stepwise changes from top to bottom, even the subtlest of which will represent an enormous scientific achievement.

I think that window into the Mars past is very important, regardless of what exactly we'll see.

Speaking about the possible entry points, today's (sol 1210) imaging plan include the following sequence:

01210::p1991::04::2::0::0::2::0::4::navcam_ingress_route_1bpp_pri17

Maybe we will have a hint about how they are planning to attack Duck Bay.

Maybe a Swan d®ive into Duck Bay

Today had been my prediction for when Opportunity would enter the crater, so it looks like I was a little early in my guessing (not anticipating the full amount of time we'd spend studying the dark streaks and lump of good hope).

That sure is puzzling, that they're imaging with navcam. Currently a navcam frame covers the entire width of Duck Bay.

They're obviously trying to find a clear path down between all the puddles on the slope... they don't call it "Duck Bay" for nothing...

Click to view attachment

Ho no Stu It's too funny
Can I swin in your Duck Bay

Boy, Stu -- if that's the case, I'm sure glad they didn't name it Gator Bay!



-the other Doug

Most activities take longer than we expect. When I first calculated an entry date (before posting my official guess) 1189 looked to be accurate. So I took that number and automatically added 30 Sols to get my official prediction of Sol 1219. I never actually thought my guess would be this close!

Tesheiner says it will be another week or two before Opportunity enters the crater. That puts my guess within optimal range. But again, it will likely take longer than we expect. So...maybe I shouldn't say anything else.

I'm not a geologist but I find the stratification visible in Victoria Crater absolutely fascinating. Close up examination of the different strata would definitely be of interest.

Going into Victoria Crater is really a "no-brainer". Any of MER-B's wheels could freeze up at any moment resulting in the rover becoming near immobile like MER-A. Sudden electronics failure is a high probability due to the wide Martian temperature cycling. Aggressive exploration is the wisest course given MER-B's state-of-health. However, it's too bad MER-B couldn't circumnavigate the crater....

I agree. It would be wise to enter ASAP.

If a wheel goes before we enter, then we probably will still be able to enter; but we might not be able to get as close to the cliffs as we want. Getting close to the cliffs is important. If we make it from ingress to egress without a disabled wheel, then there will be plenty of time to circumnavigate counter-clockwise to get close-ups of the rest of the crater. Perhaps we might make it to another ingress somewhere!

Ah yes, the pools of water magically clinging to the slopes!

We can't forget Astro0's brilliant depiction of this great migratory rest stop!

I hope Otis Redding doesn't object to this but we're not...sittin on the duck of the bay, wastin time...are we?

Is that an underhanded way to remind us of the recent IEEE Oops.

You're right. Genius, absolute genius!