Hopefully, this means we just got at least 1.1 amps out of the solar array.

Here's hoping this is a start to recovery. No way a sure thing yet, but fingers and toes all crossed...

-the other Doug

Hmm... I know dust storms "puff up" Mars' atmosphere, making the average air column be deeper and thinner. I believe this is due to solar heating happening at the tops of the dust clouds more than at the surface.

I wonder if such a puffing up of the atmospheric column would make adiabatic cloud formation at higher altitudes more likely? It sort of appears so.

-the other Doug

Outstanding!

I have one thing about which I am curious. The final of the three images states it was taken while its rover was in mid-hop. I'm wondering why any hopping activity was occurring without any commands sent from Earth -- I didn't see any indication of pre-programmed hopping set up in the deployment and landing timelines that JAXA posted. And from the other statements made, both pre- and post-landing, I can't see any indication that hopping actions were commanded during this time.

I *did* see something that indicated that the rovers were expected to "bounce" and take a good 15 minutes to settle down onto the surface in a stable, non-moving attitude.

Could the caption which indicates the rover was hopping really indicate that it was in a bounce and not in a deliberate or commanded hop?

The difference would be like stating that, say, Opportunity was "roving" as it bounced to a stop within Eagle Crater...

I wonder if they missed again. Or hit and bounced completely off.

Ah, well -- I suppose we'll have a better idea tomorrow. At this point, I guess I'm not anticipating good news...

-the other Doug

So, a nice build-up, a bunch of tweets right up to separation, and then... nothing?

Huh? Am I missing something? Is there a secret forum or thread somewhere in here where the current status of the mission is actually being discussed?

Here is the image posted, taken from the JAXA web page, at 4:19 UTC. Likely taken as much as 30 to 40 minutes prior to Minerva release.

IIRC, false alarms are not only possible because of false contacts that end up being chatter with other assets in the region. I recall that there was a repeated set of false alarms during the active contact attempt phase with MPL back in '99, up to the point of a news release that there had been a signal detected that could well be from MPL. And all it ended up being was a reflection of the signal being sent out to MPL, not anything back from the crashed lander.

As Mike and Doug and others keep preaching, false alarms are quite possible, anything that appears to be a contact needs to be verified as two-way and containing at least valid headers in the downloaded data stream. In other words, while you may get a heads-up looking at the DSN status, the real proof of the pudding will be when downlinked data, if any, is analyzed and found to have valid headers. And valid engineering status data, hopefully...

And, guys? If the worst has happened and Oppy has finally gone on to meet her sister in whatever afterlife exists for such entities, it's not a sad time. Fourteen years of impressive and fundamentally game-changing data from a rover designed to last 90 days is not something to mourn. It's something to celebrate! Oppy doesn't deserve a dirge, she deserves a happy, rollicking Dixieland funeral parade!

-the other Doug

Thanks much, Doug!

Thanks, guys. The technical discussions thus far available had not been much help for me to understand what the thresholds are for a MER re-animation after a major dust storm event. I've got a much better idea now. This is exactly the discussion I was hoping to see, again much thanks.

And yes, we don't know the dust loading, but as Mike pointed out, it's got to be between 0 and 1, thus providing a range on a graph that must, when added to the tau range and the minimum charge required for the rover to start up again, define the conditions required to get to a re-activation of Oppy.

In my mind's eye, there is a graph, sort of a Venn diagram, of those three sets -- tau, dust loading and resultant power -- and the area where they overlap is the area in which we can expect a successful re-activation. And it would surprise me no end if such a graph does not exist for all you JPL types to see. I was just trying to get some insight on what the ranges are in each of the major categories, and how each sort of generally plots against time, is all.

But, yeah, planetary exploration via Venn diagramming...


p.s. -- Even with all the times lately (and yet upcoming) I have had to undergo surgeries, and get another few million brain cells whacked by the anesthesia, I am still swift enough to understand that there is not a magic date on a calendar beyond which the situation goes from "we're confident and optimistic" of recovery to "let's declare Oppy finally dead and have a wake for her". Like I say, I was just trying to get the shape of that Venn diagram I mentioned straight in my head. Again, thanks!

So, at what point does it become concerning that we have not yet re-established contact with Oppy?

There has to be some point at which orbital and telescopic data would indicate tau in Meridiani is at a low enough level that, if Oppy is going to be recoverable, we would begin to expect to hear from it. My guess is that a fair number of people working on Oppy have a good idea of what this timeframe is -- or, failing a timeframe, at least at what level of clearing we ought to start reasonably expecting contact -- but as of yet, I've seen nothing, not even speculation, as to when this might occur.

Again, not so much against a date as against a tau level -- at what level of clearing do y'all think JPL begins to seriously expect to regain contact, if such will be possible?

-the other Doug

Well, it is very clear that this is indeed Philae. We can now compare some of its surroundings as they now appear to what they looked like in the CIVA pan. It looks like a lot of nice details show up here in that underlying sheet-like surface, that showed up in such great detail in the CIVA pan, at any rate. There may be some good ability to compare/contrast and look for changes.

One thing -- from the obvious orientation of the two visible legs, it looks like there should be a leg pointing almost directly at the observer's position. I don't see any signs of it, and yet I thought all three legs were seen in the CIVA pan. The one I can't see here would be the one that looked like it was pointing out at the sky, with no surface around it.

Do y'all think it's just that the one leg is hard to see because we're looking right down its length end-on? Or am I mistaken about the CIVA pan, and maybe Philae lost one of her legs in her final sequence of collisions?

-the other Doug

The presence of clays implies rock altered in an aqueous environment. With proposed subsurface liquid water deposits, either ancient or current, within each of these bodies, I am thinking it's not difficult to understand how such clays form. How they got to the surface, that's another matter, though I imagine impacts have had something to do with it...

-the other Doug

Hmm... the clasts are surely unsorted, but there are some rounded clasts, especially amongst the smaller ones. I see a few rounded nodule-like things, too, that might be lapilli or even concretions.

I wonder what the matrix is composed of? Almost looks like soil or regolith breccia, but I doubt that would be strong enough to have held up for as long as it seems to have. Very fine-grained, though, almost sugary-looking, unless the ubiquitous dust covering is fooling me. With a large admixture of very small dark gray clasts, most of which are angular but a few of which are rounded.

I dunno -- the clasts don't look very shocked, it just doesn't feel like a breccia to me. It looks more like a surge flow of some kind picked up a lot of the small angular rocks in its way as it came though. A wet landslide or the outside edges of an impact surge, perhaps?

It looks mostly like poorly mixed concrete with too much aggregate in it, to be honest. Again, I think a good feel for what the matrix is composed of might give a better idea of how it formed...

-the other Doug

If the Nature Geoscience article is accurate, then what we ought to look for, perhaps, would be the impacts of the two larger moons that their theory predicts spiraled in and impacted Mars.

Two of the best candidate sites for such impacts, I would think, are Hellas and Argyre. Interestingly, if these are impacts from the two moons predicted by the above-mentioned theory, and if those moons, like Phobos and Deimos, were in low-inclination orbits, then at the time of the impacts Mars itself had different rotational poles, with a lot of what is now the southern hemisphere sitting along the equator. Considering it has been theorized that Mars did have a significant rotational pole shift after the huge piles of Tharsis lavas all got built up on one side of the planet, the whole thing re-orienting to place the greatest mass of the Tharsis bulge along the equator, this could account for seeming high-inclination impacts which may actually have been from low-inclination moons -- it was the surface of Mars that changed in inclination, so to speak, rather than the moons' orbits.

-the other Doug

The cameras on the descent stage will obviously need to send and store their data real-time to the rover, obviously, for transmission back to Earth after landing.

Is there any advantage to making this a wireless connection, which can then also provide video from rover release to the end of the fly-away maneuver? That could provide an initial low-level flyover of a section of the local terrain where the rover won't likely be allowed to go (contamination issues), and give more data about the entire site. Sort of a first survey along the lines of the proposed hopper-copter's aerial surveys. This could even use the same radio data channel that will later be used to connect the rover to the hopper-copter.

I'm just trying to think of ways to get the maximum value out of these cameras. Besides the extreme cool factor, of course...

-the other Doug

I could see pushing a "top hat" mast out of the top hatch of a landed Red Dragon that included a solar cell panel and maybe something like a camera (Mastcam? Pancam?) on a moving, aim-able platform, and/or a flight spare of ChemCam on the same or a similar moving platform. Things that don't need a rover's mobility to operate, and yet can return some decent science information about the landing site. And a package that perhaps could come off the shelf as flight spares from current active probes.

I'm sure there are a number of options being discussed right now, and if any science payload can be included and easily deployed, we'll likely hear about it in the next few months.

-the other Doug

Of course you did. Sometimes I can sound like an idiot without even trying very hard.

Sorry, it was just the logical thing that popped into my head. I plead pain meds (had an emergency surgery a month ago, to fix something that wasn't connected back up right after those major surgeries I had two years ago... sigh...), it seems like all those little inner voices you can normally filter out keep popping out, in my posts and my conversations. Certainly no offense meant.

I'm still fascinated by an impact that could generate relatively strong seismic signals and yet not seem to leave any obvious crater. Gonna have to think about that one.

-the other Doug

Umm... USAF donated unflown optics from recon satellites that were never launched. In specific, the one I recall is the donation of the mirrors from the first MOL (which was also a spy sat) for scientific purposes.

You won't be able to just decommission a KH-11, hand it over to NASA and say "Here's another Hubble." I don't believe those cameras can even be set to focus out to solar system objects, much less other galactic and extra-galactic targets. And trust me, it will cost a heck of a lot less to build new mirrors than to harvest mirrors already in orbit.

So, yeah, I don't think the old KH-11's can be converted to astronomical telescopes. If I'm wrong, I'd love to hear about it. But I don't think I'm wrong...

-the other Doug

All of the LM ascent stages were grazing impacts, but all of them caused rather strong seismic signals, picked up quite clearly and distinctly even by seismometers emplaced hundreds of kilometers away. The fact that the A16 LM ascent stage impact wasn't noted on any of the seismometers I always put down to the likelihood that it impacted on the far side, with most of the Moon's bulk between it and the seismometers.

You would have to think that anything that generated such seismic signals would have created a crater, wouldn't you?

It also seems to me that the dark streaks seem radial. If you ran lines back along the streaks, wouldn't that point you back to the origin point of all of them? There couldn't have been a lot of interactions that would have sent off debris on non-radial trajectories, so most of the streaks ought to point directly back to the impact point, right?

In re LAMO 45 again, not only do we see boulders up to at least 200 meters in their longest dimension, with an awful lot in the 50-meter range, the immediate ejecta blanket is extremely distinct, particularly the extraordinarily distinct edge of the ejecta blanket itself. Boulder streams are also well aligned with the patterning in the ejecta blanket. This is a wonderful example of impact cratering, actually...

There are literally hundreds of 50- to 500-meter craters in the imaged terrain outside of the ejecta blanket, while there are less than 10 of that size (and less than half of that are 500m or more) on the imaged portion of the blanket. In fact, much of the ejecta blanket is entirely crater-free; what patches of craters that do appear in a couple of spots look like they may be patterns of secondaries from only one or two close-by impacts.

We don't have an empirically derived impact flux for Ceres, but I would think a surface this crater-free would have to be awfully young, geologically speaking. Hence my enthusiasm for a very young-looking crater, here...

-the other Doug

Um, wow... that has to be one of the freshest craters we've seen in the LAMO campaign. Look at all those boulders!

Um, again -- I should know this, but, what size are those boulders? A lot of them are three or more pixels wide, what's our pixel resolution from LAMO right now, on average?

edit -- I asked above because I doubted this, but is it true that the "dot = 35m" at the bottom of the image really means we have 35 meter resolution? If that's the case, some of those boulders are 300 meters across, or more.

-the other Doug

Thanks, Phil! That did it.

-the other Doug

Oh, I can see it. Just can't download it unless I register with Flickr, and I don't like doing that kind of thing on general principles. And that hasn't changed, it still tells me I have to create an account.

-the other Doug

And there goes Flickr again -- "You've found a picture to download! Just sign in! Of course, you understand that we can't just let any riff-raff download these images..."

Disgusting.

-the other Doug

Considering the extensive emplacement of impact debris mantling units all over Ceres, I would guess the top 500 to 1,000 meters of the surface is a battered, crushed layer of poorly mixed, brecciated debris. There are quite likely a huge number of salt and salty ice deposits embedded within this debris layer.

When craters are made in this kind of surface, these pockets of high-albedo salt (or salty ice) become exposed; more are exposed as mass wasting deflates large crater walls. Thus, the occasional white spots and streaks seen in crater walls.

Now, this is completely separate from directly-emplaced cryovolcanic deposits, like what we appear to see in Occator. Those (and there are quite a fewer number of them than the smaller white spots) seem to be examples of deeper material moving volcanically up to the surface from deeper layers of soft salty ice (or even liquid salty water). That's a different emplacement mechanism from most of the small bright spots we see on crater walls, I think.

Think of it this way -- take a surface composed mostly of black sand, and randomly embed a bunch of white pebbles in it. Then hit it with an impact. Your resulting crater will show mostly black sand walls, but every once in a while a white pebble will poke out through the major black sand matrix of the unit. And as crater walls recede due to mass wasting, new white pebbles are exposed. Now, just replace the black sand with the general dark material of Ceres' surface and the white pebbles with concentrations of salt and/or salty ice, and you have a model for what may well be happening on Ceres.