Friday, December 16, 2011

100 Sols on Cape York — An Absurdly Brief (Read: Long) Summary (Part 3/8)

Part 3: The Odyssey Crater Ejecta Field — Zinc at Tisdale-2

~2690 to 2703
"tl;dr" Description
We found this thing that looked like a gold-plated aircraft carrier. So we looked at it… really, really closely.
Highlights from Matt's Notebook
Sols 2692-2693: 
> Some… ahem… involved… discussion at sequence walkthrough, but all is well. VisOdom for the win.
Sol 2694: 
> Today's Secret Woid — "bogy" — and I just checked behind me to see if the computer was about to murder me.
Sol 2695:
> Ecam PUL: "Is that what you said? I thought I heard something else…" // RP1: "You did, but we don't hear those voices."
Sols 2703-2705:
> Planning an escape from the clutches of Tisdale-2 tosol! We'll be back.

Details ("the deets")
I didn't have another shift for some 2 weeks after the first arrival at Endeavour and Cape York. I was in the loop only because I like to walk up three flights of stairs from my office to catch the SOWG meetings. 

Suddenly we had driven to straight into the Odyssey ejecta field and I didn't know left from right. Good thing I'm not an RP. There was all this hoopla about these "Tisdales" and this "Ridout" and, for that matter, why there hadn't been a TAP/SIE Album of the Day in so long.* Tisdale-2 was right in front of us and it was to be our first Endeavour victim.

The challenge presented by Tisdale-2 was twofold:

1) From a few meters back, pick out targets on a very rough rock with interesting features from Pancam imagery, interesting features that were not unambiguously smooth for all the touchy-feely that we'd be doing to it. (With the IDD! With the IDD! Come on!).
2) Actually IDD the damned thing.

One could say that we could have pulled right up to it and taken the close-up Pancams to get ourselves some nicer ideas of good targets, then "bumped" or simply turned to our selected target. Two sols, snip snap done. Right? Nope. One would also be pulling a classic "jumping the proverbial gun" in this case, because that plan would, well, take two sols. We like to take a little bit longer looking at our options in the morning when the downlink rolls in and then nail that drive in one sol. We are a success-oriented team, in more ways than one. Only rarely do we try to get part of the way there and correct thereafter; only rarely do we try to get part of an image or part of an APXS. We only do that when we have to, like when we're restricted by available time in the Martian day**.

The lesson: trust that rover. (Also, the RPs. But, you know, they smell like robots***, so…)

While we planned the approach and ramifications thereabout, the scientists planned their targets. The strategy of an approach drive is, by the way, relatively independent of the final target, since that final target just becomes a parameter somewhere that we change with the click of a mouse. We can get a detailed engineering backbone prepped for when the science team finally comes along and says, "Here, please." For this approach, a VisOdom hiccup (well — feature) gave them an extra day to look and decide. Tack on some tough love for good measure and they decided on two targets for more thorough discussion:

Fake color, by the way. Rookies. I got you good, didn't I?

Clearly, neither was smooth enough to be brushed. Not even the top of the entire rock, with a coating of a composition that we still don't know because we never sniffed at it before moving on, was even close to acceptable. The Rock Abrasion Tool (RAT) is a consumable resource — brushes and grinders and stuff wear out. No point in wasting it here. No worries, because we still had the Microscopic Imager (MI) and APXS (… scatterometer-science-gathering-thingy-mabob) to go at it.

Of course, there's a critical show-stopper for Oppy's arm: A bad shoulder joint has it canted to the left at a few degrees. Also, we don't allow IDD and drive activities to occur without ground in the loop in between them (except for things like the "stow and go"). Combine these two pieces of information and you get the result that if we've approached a target for an IDD campaign, and if we want to choose a new target that's at a different rover-relative azimuth (rotation clockwise or counter-clockwise looking down), it takes two sols — a "bump" or small turn and then the actual IDD work — rather than the single sol to just move the shoulder joint if it actually worked.

Keeping this in mind, the science team chose Target A for surgery. We got an initial taste with the MI and APXS by working in the so-called "workplane" of the IDD, a literal 2-dimensional plane created by the stuck shoulder joint. We took that initial taste, turned it on its head, said it wasn't enough, and did it several more times. Since Tisdale-2 was so rough and rocky on its side, things stuck out. We could reach a few target points with the gunsights of the MI and APXS with a slight roll out of the workplane (roll, pitch, and yaw are independent, children!). All told, we captured a nice chunk of data, a veritable dart board for the ages:

(with MI's overlaid on the second image):

Significant tasty herein.

After less than two Mars weeks, the results from the AXPS were in. At least, in and prepared for a news conference, since we knew everything the day after the data was collected (plus or minus a good downlink with Odyssey and MRO — space only plays nice sometimes!):

Real, actual science.

This tells us that there is an unusually high zinc content in Tisdale-2 compared to the other rocks examined by both Opportunity and Spirit. Not only unusually high, but drastically high — that's a logarithmic y-axis. The one-sentence explanation of this big adult word is that if the change is big on a logarithmic axis, it's huge on a linear axis. Which means stuff. And, remember, stuff means science.

Without much of a fuss, the RPs took the keys and candy-cane'd us out of there:

Next up: Sniffing down a RAT-able target — and finding one that smelled kinda funny.


*Actually, nobody cared, which, you know — expected. One of them was a doozy: Wish You Were Here by Pink Floyd. By the way, Newton's 4th Law: You can't turn "Wish You Were Here" down. Universal implosion, black holes of death-inducing doom, trolls who steal your coffee. The usual.

**Example: Last week we couldn't put together a full 2x2x5 MI stack of Boesmanskop at Winter Haven because of lack of time in the day; we got bottlenecked by a few standard engineering things. So, instead, we planned two 2x1x5 stacks.

***Like solder, incidentally. But the good kind, like whatever the kind is that talks, eats, drinks, drives rovers, and makes me smile. I guess this means that I would accept Cylons into our world.

Wednesday, December 14, 2011

100 Sols on Cape York — An Absurdly Brief (Read: Long) Summary (Part 2/8)

Part 2: Landfall at Endeavour Crater — Cape York and Odyssey

~2680 to ~2690
"tl;dr" Description 
We made it! We made it! We made it! Ohhhh look at the pretty!
Highlights from Matt's Notebook
Sols 2683-2684: 
> "This plan is skinny by design." - Ray — interesting, since we're at Odyssey. LIKE, COME ON.
Holy crap we're here!
> "This is somewhere." — Posted a picture next to my cubicle. Nobody noticed except for my boss, who is, you know, supposed to care.

Details ("the deets")
Suddenly… arrival, Monday August 8, planning sol 2681 (-ish, depending on what one considers "there" to be). We hit the southern tip of Cape York and parked next to Odyssey crater, which was a landmark close to the non-specific "Spirit Point" locale that identified our arrival:

"But, Matt, Spirit Point isn't a point." Don't care.

"Hey, isn't that your blog's background?" Perhaps, but the demon in me says it's Photoshopped.

Of course, that second image confused everyone in the wide world outside of the MER enthusiast: With headlines like "Opportunity Arrives At Giant Endeavour Crater," you might expect the panorama that actually showed as much of Endeavour as possible, but instead most folks passed around that image of Odyssey, which is in the 10-15 meter diameter range, and said, "That's not that big. I'm already bored."

We had to throw on the brakes, hard. Suddenly, drives were precisely targeted and the entire mission changed. At least, it did from my perspective — the only Oppy I ever knew was the one that silently trekked hundreds of meters across the Meridiani at a time. A little poke at a rock here, a little imaging of a shallow crater there, nothing much. Then it was wham, we're back in this science collection gear that I'd never seen before. We weren't driving just to drive, or IDD'ing just to IDD, but we were doing those things to do other things

(And, honestly, it made the science team's role that much more apparent to me. It's an obvious thing — you know, we're there to do science in the first place, Matt — but I don't get obvious things very well. In the Meridiani, I looked at them as if they were the last remains of the mission that used to be; now, they were front and center. They owned the mission.)

The Odyssey Crater was the first thing that captured our attention:

What, you don't have your red-blue glasses? What is this, amateur hour?

And, to the east, towards the inboard side of Cape York and Endeavour itself, a nice ejecta field from Odyssey's creation:

Stu's black-framed images make me look classy, don't they?

The goodies — those smectites and phyllosilicates — were located somewhere in the middle of Cape York, or north of our "entry" point on to Endeavour. At least, according to orbital imagery and remote sensing. We shirked the direct path to these targets mainly for several reasons:

1) Cape York dips down into Endeavour on the inboard side and instead of poking our head over the proverbial edge didn't seem to be a very prudent way of attacking Cape York as a whole.
2) The true traversability of Cape York, especially on its inboard side towards the center of Endeavour, was unknown until we had some imagery from the rover itself. Our RPs took a look at Cape York and identified two paths: one that would have approached from just north and west of Odyssey, and the one that we took, from the south side and working northward to capture as much of Cape York as possible.

I've illustrated these paths on this perspective Google Mars shot of Cape York that I stole from Stu near sol 2680:

Conveniently, "A" stands for "actual" and "B" stands for "backup". I will pretend I knew this before I made the annotations to the image, and you will faithfully affirm this delusion for me.

Remember, these were notional only, meaning this was a strategic plan. As we'll find later, Path A actual curved back north much sooner than indicated here. In any case, the immediate advantages to path "A" were that nice ejecta field from Odyssey for analyzing and poking and sniffing. Odyssey not only had its own story, it also exposed the internal bits of Cape York itself. Another Google Mars shot from Stu's blog gives us an idea of where we stood:

Right in our gunsights was Tisdale-2. On approach just a few meters to the southwest of Odyssey (and its large, perched rock, Ridout), here was our view this aircraft-carrier-looking beauty:

If you still don't have your red-and-blues, don't come back until you do.

But, wait, Tisdale-2 was a whole new treat, a whole new taste, the start of this new mission. So, just as this "phase" of the Endeavour Campaign was short — roughly 10 sols by my arbitrary estimate — so will this part of the story be! 

Monday, December 12, 2011

100 Sols on Cape York — An Absurdly Brief (Read: Long) Summary (Part 1/8)

Just as you might expect for a young-gun Generation-Y'er, I'm wired. I use my iCal, Mail, and everything else in my Macbook to manage my world. ("Manage the crazy. Bring out the talent.") I need things to be organized, so rightly placed and micromanaged that it would make a normal person wonder how (or why) I'm not on Ritalin. However, I have one holdover from the olden days. That holdover?

The notebook.*

Don't get me wrong: I am a fan of TextEdit and other flat-text, note-writing programs. Who needs all that markup, right? But there are so many places to put files that you forget not only what you named the file, but what's in it. With a notebook, it's all right there, ready for consumption, with perhaps a little page flipping.

I have several notebooks for work. First, one for all my multi-mission work — you know, the Juno's and MRO's of my world. It's got scribbles and notes and it's a total brain scatter. I love it. Organized, but not. Second, one for logging my days. Like a work journal, but abbreviated and totally half-hearted. I tend only to log the more important days, because those days are usually filled with actual work and I have less to write ("7am: MER shift. 7pm: Sequence model development for MSL.") Third, one exclusively for MER. I never kept a MER notebook until I felt it was important enough. That time, that crossing the threshold of "important enough," was when we hit Endeavour Crater. Rightly so, the notebook is named "The Endeavour Campaign." 

This notebook serves the purpose of reminding me of what I did on each of my shifts — new tricks, bug fixes, engineering tidbits, that sort of thing. I never thought it would turn into the monster that it did. A few weeks ago, someone asked me a question to which I had the answer in my notebook; I couldn't remember where it was, so I started flipping the pages. "Geez, it's right here, gimme a sec… Hang on, I know I'm close… Man, I've written a lot…" 

As it turns out, "a lot" is about 100 pages in 100 sols.

Holy crap, we've been here 100 sols!

To drive it home further, a former-colleague-and-classmate-now-new-colleague-and-MER-TDL-in-training-and-drummer-in-my-Sunday-jam-sessions friend asked me today, "So I've seen all the news stories about the Gypsum find, but nothing yet from your blog. What gives?"

Well, trees give. They give very easily, in fact. He understands my pain, though: we both experienced 50 hours without power at our respective houses. Even so, this blog has been empty for most of December. What else has been going on? 

This post, is what!

I've been prepping this post for a few weeks. I have this uncanny ability to steal pictures from the various Cape York UMSF threads and Stu's blog. By steal, I do mean borrow with credit (Stu said I could! I swear!). I also have this uncanny ability to be incredibly wordy. So, onward!

(Courtesy Dr. Awesome XVII)

My intent is, as always, to provide context and insight into what happened these last three months. You can expect a little chaos here: 8 parts, each with the intent of informing people who aren't so in the loop as some of us are. The purpose is to be a summary, so if you know what happened, don't spoil it you crazy goons.

(Remember: For full-size images, click them!)


Part 1: The Approach to Endeavour Crater

[forever ago] to ~2680
"tl;dr" Description
We drove for, like, ever.
Highlights from Matt's Notebook
[No notebook! Boooo!]

Details ("the deets")
About 1000 sols ago, the Opportunity rover was commanded to drive away from the Victoria Crater. Having expired her manufacturer's warranty nearly 20 times over already, the team said, "There's this large-ish hole in the ground, way over there, so let's go. Who knows?" 

When describing this new mission for Opportunity, Project Manager John Callas could make no promises for when we'd arrive at Endeavour. It was 19 kilometers away (not quite as the bird flies) — more than Opportunity had already driven in its 1700 sols on Mars. And there was all this stuff in the way, like the Purgatory dune field and small craters and rocks everywhere. His — the team's — best guess was, "When MSL lands in 2012. Maybe." Our target was this little guy on the west side of Endeavour, named Cape York:

(Ignore the red circle on the second image.)

For an idea of the size of Cape York, check out Stu's post. That third image is a perspective view looking roughly north, giving you an idea of how it bends in towards the center of Endeavour. Spirit Point was the destination, the small Odyssey crater being a nice landmark for us to shoot at.

Somewhere in that journey, near sol 2310, I joined the MER team fresh out of school in Colorado. From the start, I noticed this curious little countdown meter in the LTP (Long Term Planner — someone who represents the SOWG) reports when the most recent traverse was shown in aerial imagery from the MRO spacecraft. This countdown meter counted down the distance from Victoria Crater to Endeavour Crater. The number was in the mid-40%'s when I joined, and that last 55% was a seemingly insurmountable task. We chipped away, little by little, and suddenly that number was 80%… 85%… 90%… All we would see in the LTP reports were images like this:

Very tantalizing. "What's it really going to be like when we get there?" we found ourselves asking.
Then we did this whole thing: 

And we did it a year ahead of schedule. Neat.

To capture the journey, I spent a few hours going back through every LTP report since sol 2310 and picked out a traverse roughly every 10 sols to build a "distance traveled" plot. (The maps posted at the MER website don't have the detailed Ohio State maps with the countdown meter as often as I need them. The information could also be found in the Google Mars maps that Stu and company make, arriving at the same answer.) This plot? Oh yeah, it's right here!

Several things here: 
> I layered in text annotations of targets and key events to give us some context.
> The left-hand side (blue line) is the percentage from Victoria to Endeavour ("V2E") according to the Ohio State traverse maps. 
> The right-hand side (green line) is the distanced remaining, derived from the V2E line.
> Not all meters are created equal. More on this in a minute!

Cool, right? ("Right!") 

The obvious trend in here is rough, linear progress. The other obvious trend is the long stop at Santa Maria for an extended science campaign and Solar Conjunction, or when the Sun gets directly between the Earth and Mars, from December 2010 through February 2011. Also, note the other key events. My favorite is what I'm calling the "Squyres Week," when Steve Squyres came in on a Monday and said, "I'm SOWG Chair all week and I want half a kilometer by the end of the week." Sure enough, that week's Mission Manager report proudly toted nearly 600 meters of drive distance in 5 planning days. 

Now, some explaining is in order. The distances reported in the were based on the so-called "Pink Path," which changed as we approached Endeavour. Therefore, I say the phrase "not all meters are created equal." Meaning, a given meter of progress towards Endeavour is not the same as another meter of progress at some other point in the journey if the Pink Path changed. Which it did — a lot! The arrival point was always Cape York but the twists and turns between Victoria and Cape York changed quite a bit.

We get a notion of "speed" (literal meters per sol) of the rover by looking at the slope of the "percentage progress" line (or the negative of the slope of the "kilometers left" line). We see that before and after the long hiatus at Santa Maria the slopes of the line is generally linear and about equal. We were just a little bit more of the "PEDAL TO THE METAL, BABY!" persuasion after Santa Maria, so why does it seem we did the same meters per sol as before Santa Maria? Because the Pink Path got longer! A given meter of progress after Santa Maria was not the same as before Santa Maria, because the SOWG got together and picked all sorts of cool little targets along the way.

(A way around all of this is to use actual drive telemetry — actual distance traveled every sol — to get a better notion of speed. But that's proprietary and painful. No thanks! Plus, the "V2E" count up is a little more fun to look at.)

Right. So. Speed. (I almost typed "velocity", but, you know… it's not that.) Why don't we just take a look at that directly? Ok!

Indeed! The speed shows up a little more obviously larger in this figure. There are two trends: first, an increase in speed — an increase in us wanting to get to Endeavour; and a cyclical "up down" pattern along this linear increase in Endeavour-wanting. That increase in speed was enough to overcome the effect of the Pink Path increasing in length! That's fast.

But, why is there a second trend? Why does it wobble? Shouldn't it be prettier?

No! Of course not! That pattern is, nearly precisely, the cycle between Nominal and Restricted planning! Remember: in Nominal, we can plan a drive every sol because the timing of uplink and downlink sets us up to know what happened before planning tomorrow; in Restricted, we can't plan a drive every sol — more like every other or every third sol — because we don't have "ground in the loop". I found this fascinating, if not completely ultra cool.

(Also, ignore that noisy large bit at the end. That's an effect of the Pink Path changing more wildly and our indicator of "progress" breaks down. The rest of the values before that noisy bit square nicely with approximations reported daily at our tactical meetings -- "assuming 65 meters per sol" was a common phrase towards the end!)

Along the same vein of "progress" indicators, here's a series of four high-resolution Pancam images of Endeavour from sols 2410 to 2681 (skewed towards the end of the timeframe because I'm lazy):

Then we have the famous Navcam Movie, another indicator of progress for the entire journey. And, as noted in the progress plot above, there was the appearance in the LTP reports of the vertically-exaggerated "Endeavour 'Fall Away'" GIF that I found on UMSF:

Hey, you know, that picture was an event in itself to me because suddenly Endeavour had opened up, like HEY EVERYBODY, EVERYBODY HEY. Simply stunning.

So what, right? We went a long way and we have all these great things telling us about the journey. Then? Then what, Matt? Is there something to the end of this story?

How about this: You all quiet down and stay tuned for…

Part 2: Landfall at Endeavour Crater: Cape York and Odyssey

(Tomorrow, maybe!)


*Not the movie. Oh god, please not the movie. Anything but the movie. I kept this phrasing because it feels so, I don't know, poignant. Or something.

Friday, December 2, 2011

No electrons

Currently blogging from a Starbucks because of this (at my house):

And this (at JPL):

There's currently a major lack of electrons (read: electricity [read: internet]) in my part of Pasadena, and I probably won't get power back until Monday.

Until I get my damaged house in order and find the trash cans that blew down the street somewhere, I won't be able to get back on the blogging horse. 

But, hey, I've got a goodie for you. In the post queue:

100 Sols on Cape York

It'll be a good one. I promised Stu that I'd have the post done a week ago, but then I forgot that we had to launch MSL and, well, you know how those things go.