Opportunity Rover Arrives at Endurance Crater

Mean_Nishka writes "After weeks of driving, the Mars Exploration Rover Opportunity has arrived at 'Endurance Crater.' It's a scientific treasure trove with an extensive outcrop of layered bedrock, and scientists will have to decide whether or not to send Opportunity inside for a closer inspection without getting it stuck forever - there's more information via a Monterey Herald/AP article."

Comments

Stuck Forever?

[alpinist]

I doubt it would get stuck there forever. I'm sure the Chinese will be more than happy to pull it out and bring it back to Earth so it can be kept at the Beijing Smithsonian.

And?

[Black_Logic]

NASA sent the twin rovers to Mars to prospect for geologic evidence of past water on the now dry and dusty planet. Sooo... Did they find any?! Did the article writer not know, or was it not considered interesting enough to print. :)

On a side note, I don't understand the design of these rovers. Seems like they're dangerously flippable. If that happens, they're pretty much junk, right? Do they have any way of correcting themselves if one tread climbs up onto a rock and it tips over? Why not have 5 or 6 treads around the center and have the middle gyroscopiclly right itself?

Re:And?

[Black_Logic]

My understanding was that this article was about the specific crater, Endurance. From the line you pointed out to me, "Opportunity revealed the Eagle crater outcrop formed in water; they now want to know if that was the case for the deeper - and thus older - rocks in Endurance." it's seems as though knowing whether other rocks, such as the ones in the endurance crater were formed similarly. So, my question was, do they not know yet? They've got images, are they only preliminary images? Do they take time to analyze?

Re:And?

[Anonymous Coward]

On a side note, I don't understand the design of these rovers. Seems like they're dangerously flippable. If that happens, they're pretty much junk, right? Do they have any way of correcting themselves if one tread climbs up onto a rock and it tips over?

I think you've been watching too many episodes of robot wars where a robot gets flipped over and becomes helpless! :)

The rovers don't have a self-righting mechanism, but they might be able to do something with the instrument arm. NASA has done extensive testing of the rovers to determine the performance envelope.

The rovers don't move very fast, and with the cameras they can accurately map the terrain in 3D to avoid trouble spots.

Why not have 5 or 6 treads around the center and have the middle gyroscopiclly right itself?

They are limited by size & weight, and they want to carry lots of scientific instruments - that's the tradeoff they had to make. Given that the rovers have greatly exceeded their expected lifespan, I think the designers did a great good job.

Re:And?

[Mycroft_VIII]

Ahhh, sorry I misunderstood your question. Odds are they don't know yet. It will take time to gather evidence. And considering thier discussing whether or not to enter the crater at all, I would assume they don't have any significant evidence yet.

Mycroft

Re:And?

[WegianWarrior]

On a side note, I don't understand the design of these rovers. Seems like they're dangerously flippable. If that happens, they're pretty much junk, right? Do they have any way of correcting themselves if one tread climbs up onto a rock and it tips over? Why not have 5 or 6 treads around the center and have the middle gyroscopiclly right itself?

Interesting point, and one which sendt me looking all over the web for pictures of planetary rovers. Seems like pretty much every rover we (ie, humans) have sendt out there is built on the same principles - wheels, no autoerect feature, seemingly hight center of gravity. So, I'm forced to conclude, they picked this particular design because it works.
It is, when talking about spacecraft, worth remembering that they are designed down - down to a volume to fit the launcer, down to a weight to be able to get where it's going, and down to a budget to get it of the ground in the first place.
Perhaps a tracked, selfrighting rover with wrap around tracks (like the early british tanks of WWI) would be a better design to use on Mars... but since it isn't used I'll hazard a guess that it's either not as suited as it may appear, or it may be too bulky, too heavy and too expencive.

Re:And?

[Gogo Dodo]

The rovers are designed to withstand tilt of 45 degrees without tipping over. At the speed that the rovers travel, I'm pretty sure that it's software is designed to stop movement if it senses that it's tilt is getting too great, it will stop what it's doing.

Of course, this doesn't work if something unexpected happens like lots of soil slippage or a rock giving way (that would have to be one large rock). The rovers are programmed to go around rocks, not over them, so the chances of it tipping over are pretty low. Soil slippage like the type Opportunity saw at Eagle crater isn't going to cause the rover to tip. It was have to be a full-on landslide.

Re:And?

[QuantumFTL]

The rovers don't have a self-righting mechanism, but they might be able to do something with the instrument arm. NASA has done extensive testing of the rovers to determine the performance envelope.

I know the rover drivers etc, and am familiar with the hardware. The idea that the IDD could right the rover would get many a chuckle here at JPL, as the IDD is not load bearing, and has very slow motors.

The torques induced when spectrally imaging the magnets alone is enough to slow down the arm movements.

If the rover is flipped over, we lose all power but batteries, and probably break mechanical components in the process. Communications may become difficult or impossible. If/when that happens, it's over.

Would make one hell of a final pancam though, the ground a centimeter away from the PMA.

Cheers,
Justin Wick

Disclaimer: I do software engineering on the mission, I do not directly drive the rovers.

Stuck there forever?

[WarlockD]

I mean really, wasn't that the point of going to mars in the first place?

I mean sure, its a long way to just put a multi-million dollar jeep, but damnit we came this far we might as well do a running jump into that thing!

Re:Stuck there forever?

[anubi]

Somehow, if we get all the way over there and fail to avail ourselves of the opportunity to see this, it kinda seems like traveling all the way to California to see Disneyland, then stopping at the ticket gate.

The rovers have a limited lifetime.

I leave it to the scientists to see this from their chair. They drove more than they expected, past the "warranty" of the rover, to get there. From now on, all is gravy. From their vantage points, they can figure out if there is anything even remotely around which would make it not worth the risk. You gotta die sometime. Might as well be doing something useful.

These ships were not made to stay in the harbor.

They've been there since Friday

[micha2305]

Well, they've been sitting there since Friday and will spent the next two sols (Martian days) looking at the crater. Here's an amazing hi-res TIF. If you ask me, it looks to steep to go down. But on the other hand, this is the most exciting target in the Meridiani plains...

Spirit and the Columbia Hills

[dolphin558]

I am really looking forward to when Spirit reaches the Columbia Hills. If Spirit successfully reaches the top of the hill the view will be breathtaking. Not only could we see the landing site but also see the actual rim of Gusev Crater more clearly. It will be an amazing sight!

Re:Spirit and the Columbia Hills

[Anonymous Coward]

What I want is to hear Mars. Does anybody know why one of the least resource consuming sensors - a microphone - has never been sent to the surface?

Ok, so maybe all you'd hear is incessant whistling of wind. Maybe Mars makes wierd noises, like the barking sands in the desert.

But for a $0.25 mic, we'll never know.

Re:Spirit and the Columbia Hills

[ScottMaxwell]

The Planetary Society supplied a microphone that we flew on MPL (Mars Polar Lander), but the mission failed. As described on the linked page, they're trying again in 2007.

BTW, in the spirit of great-minds-think-alike, the idea of sending a microphone to Mars was first suggested by the late, lamented Carl Sagan.

Re:Spirit and the Columbia Hills

[TehHustler]

On the subject of microphones, the Cassini-Huygens probe currently on its way to Saturn/Titan is carrying one, so that we can hear Titan. The prospect of hearing the first waves lapping against an alien shore is quite remarkable. If theres any liquid there, that is.

Re:Spirit and the Columbia Hills

[ScottMaxwell]

I am really looking forward to when Spirit reaches the Columbia Hills. If Spirit successfully reaches the top of the hill the view will be breathtaking. Not only could we see the landing site but also see the actual rim of Gusev Crater more clearly. It will be an amazing sight!

I'd like to see that, too. But unfortunately, the current thinking is that we won't be climbing the hills when we get there.

In fact, I just had that conversation with Larry Soderbloom, one of the top scientists on the mission. My side was, basically: "But, Larry, the view would be so cool." :-) He readily agreed, but unfortunately, there's just nothing scientifically compelling up there. (As best we can tell from orbital imagery, that is.)

However, MOC images (MOC is the camera system on the MGS spacecraft) show that there's a lot of cool stuff in the hills' vicinity, making them a worthwhile destination anyway. There are rock outcroppings on the hills themselves, which we'll be able to see fairly well even without climbing to them, and several geological features of great interest in the 500m or so around the hills. (Now that we've upgraded the rovers' flight software, we're regularly covering 70m+ per sol -- indeed, we just set a new Spirit single-sol record of 92m -- so 500m is roughly a week of driving.) As a result, that area is likely to give us our best chance of telling the "water story" we came to Gusev to find.

Incidentally, we're shooting for reaching the hills in about 40 more days (we're targeting sol 160; we just planned sol 119). Stay tuned.

FWIW, as spectacular as the view would be in other respects, I don't think the Gusev Crater rim would look any better from the top of the hills. It's faint because of the high tau (atmospheric opacity) caused by the global dust storm that preceded our landing, and which is still settling. Maybe the view would be better from a little higher, but I doubt it. The good news is that the rim is showing up better and better as the atmosphere clears, so we'll get better views of it over time even without climbing the hills. (If you've never noticed the rim in the images, you can see it in this image if you look carefully -- look to the right of the hills, at the right-hand edge of the image. It's faint, but that's the rim of Gusev Crater.)

My opinion

[smallpaul]

Sayeth the poster: "Scientists will have to decide whether or not to send Opportunity inside for a closer inspection without getting it stuck forever."

I am personally in favour of them sending it inside for a closer inspection without getting it stuck forever. Getting it stuck forever seems like it would be a bad idea...but maybe that's just short-term thinking on my part.

Nice MER Animation

[boomgopher]

Not sure if this has been posted before, but I stumbled on this today, it's quite amazing:

Mars Exploration Rover
(requires Quicktime, me thinks)

Re:There is

[austad]

. Non nuclear bombs require oxygen to explode


Bombs carry their own oxidizer. In the case of gunpowder, it's potassium nitrate. Other types of explosives use other things, including potassium chlorate, potassium permangenate, etc. There is not enough oxygen in the air to make something combustable explode on it's own, it will just burn.

Even the old school fuses you see in cartoons going to dynamite have their own oxygen source (usually a string doped with gunpowder). This is why they will burn underwater, or even in an atmosphere without water.

The problem with the rovers carrying explosives, is that the explosives would need to be buried for them to have an effect. Just dropping a stick of dynamite on the surface would cause very little disruption.

When I was like 16, I worked at a gas station. There used to be this guy that came in with a silver van that said Kaboom! on the side. Turns out, he ran a demolitions company. He'd always sit and chat with us about his destructive creations. It almost seemed like he liked his job a little too much. Nevertheless, he was always interesting to BS with.

Lomg time.

[OgGreeb]

"...decide whether or not to send Opportunity inside for a closer inspection without getting it stuck forever"

Whether it is sent into the crater or remains outside and nearby, what is the likelihood that the rovers will *ever* be recovered? Won't they then be "stuck forever" anyway? Also, they just sent the rover to this place over many days. If this wasn't the best place to get stuck, why did they bother?

Re:Don't jump to conclusions...

[beckerie]

It could very easily get stuck there. When the rover was leaving the crater that it landed in, they had a little bit of trouble because of soil slippage, and the crater wasn't all that steep.

Considering the terrain of the red planet, NASA surely would have incorporated this into the design of the rovers. They are programmed to avoid exceeding tilts of more than 30 degrees although they can tilt up to 40 degrees without tipping over.

What would be interesting is knowing how far the rovers can go. Being robots, not humans there would be a fair few limitations in their exploration.

Endurance crator? Who comes up with these names...

[chiyosdad]

Opportunity (level 3 Rover of the Martian Plains; Strength: 20 / Agility: 8 / Endurance: 10 / Intelligence: 2) finds a crater in the ground.
The crater has no distinguishing features!

You...
[x] descend and explore the surroundings
[_] circumvent the crater and continue your previous explorations

You are basked in a strange and comforting light!
+ Strength 1
+ Endurance 30!
+ Agility 2
+ Intelligence 1
You found a new item! Unremarkable Rock of Endurance (+14)
[x] keep
[_] drop

You leave the crater and continue your explorations.
You drive over a rock askew and fall onto your back, unable to right yourself!

> Cast Roll Over (level 2)

You must roll 14 or better to cast this spell.
> 1d36

Opportunity (level 3 Rover of the Martian Plains) has rolled a 08

You continue to lie immobile on your back in the cold Martian evening. Slowly, your batteries lose power and a darkness begins to come over you. As you desperately struggly against the dying of the light, your thoughts go back to your maladjusted childhood...

Re:Don't jump to conclusions...

[Mycroft_VIII]

The've actually done quite a bit of testing on rover slippage on inclines with and engineering prototype here and have a chart showing up/down angles vs. slippage. elswise when they tell it to go forward 15 meters, it may stop at 12 or go past to 17 if the weels slip (the rovers rely on sensing wheel rotation to calculate distance traveled) they've been refining this test data (which they found alot closer to reality than they had hoped) with actuall measurements since then.
Thier data indicates that at about 25 degrees an uphill climb becomes impossible because of the slippage. so all they need to do is find a usuable slope under 25 degrees in angle.

Mycroft

Re:Forever, or until the solar panels die...

[beeplet]

True. I probably should have been clearer, but I meant to ask whether NASA has any kind of updated estimate of how much life is left in the rover, given that it hasn't kicked the bucket yet. From what I understand the only hard limit on the lifetime is that the solar panels' output decreases as they accumulate dust, but I'm sure there are other contributing factors as well...

Re:Forever, or until the solar panels die...

[cyclone96]

As JPL stated here they think they may get about 250 sols out of these rovers, which is the approved duration of the extended mission (of course, I'm sure they'll keep extending it until they die, but there is a ten day communications blockage from the sun at about that time).

From The Sound of Music (Mars Edition)

[Hawthorne01]

./~ High on a hill, stood a lonely Rover, yodel-lay-he yodel-lay-he yodel-lay-he-hoo ./~ /me ducks ands runs. :-)

Now THIS is an interesting picture:

[NeuroManson]

http://marsrovers.jpl.nasa.gov/gallery/all/1/n/095 /1N136619354EFF2000P1985R0M1.JPG

Take a gander at the center of the crater. How many folks familiar with wind eroded ice recognise that kind of formation?

Re:Now THIS is an interesting picture:

[hopemafia]

As a geologist the formations in the center of the crater look like small star dunes to me. They form when winds come from multiple directions, such as the swirling winds you would get in a crater.

Mars Microphone

[mperrin]

Actually, there was a microphone included on the 2001 Mars Polar Lander, which sadly did not survive its landing. However, it looks like they're going to try again on the 2007 NetLander mission.

Of course, it's actually a $100,000 mic, but hey, that's pretty close to $0.25 in space dollars. :-)

Re:Don't jump to conclusions...

[psoriac]

I worked in my university's robotics research department during my undergrad studies. My job as a cs student was to write the motion control algorithms for a group of math grad students. The project was to develop an AI that could navigate a building and perform tasks autonomously given a floorplan, its starting location, a destination, and an action to perform.

The robot platform that they were using had a styrofoam head mounted on top of a cylinder with a pair of treads. The head had two cameras mounted where the eyes would be and two microphones mounted where the ears would be. The idea was that the robot would be able to understand simple voice commands, be able to detect transient obstacles (mostly people) using the cameras, and be able to track its location using the cameras (landmarks) and treads (distance rolled).

By the end of the semester, we actually had it working halfway decently. One issue we encountered with tracking distance using how much the treads had turned was that the treads tended to slip when turning and also on dusty/dirty patches of the floor, so that over time the internal position diverged from the actual position (which is where the cameras came in).

Now seeing as how this was almost 10 years ago and it was just a bunch of undergrad and grad students, I'm sure that the specialists at NASA have been able to accomplish something truly amazing with their rover. My hats off to them.

How Endurance Crater Got Its Name

[ScottMaxwell]

I don't know if this is common knowledge, but I thought y'all might be interested to know how Endurance Crater got its name. I don't think I'll be telling tales out of school if I relate this story. This is an excerpt from a mission diary I've been writing as a way of keeping my wife in the loop, which was especially important when we were all on Mars time and I wasn't seeing her for weeks on end. From way back on sol 3 [insert wavy lines here] ....

The most interesting part of the meeting was a fifteen- or twenty-minute discussion about naming geological features. One of the first proposals was related to naming the craters we saw in the descent images. The starting suggestion was to name them after coins, partly because people are familiar with coins and partly as a thank-you to the descent imager, which is named DIMES. More specifically, they'd be named for the people on the coins -- Washington, Lincoln, Roosevelt, and so on. To avoid being too America-centric, we'd also use coins from other countries -- especially Germany, Denmark, Brazil, and France, our international partners on this mission.

The same discussion included how to name the landmarks we can see from the landing site, such as the hills to the east and the peak to the south. The initial suggestion was to name the distant hills "Endurance Hills," for the name of Shackleton's ship (and to reflect what it will take us to get there, if we decide to drive to them), and then name other features after the members of Shackleton's crew. There's some concern about tying ourselves so closely to a mission that, as romantic as it was, was technically a failure ("did not fundamentally meet its Level-1 requirements," as Squyres jokingly put it).

A more general version of that proposal emerged later: name the landmarks after explorers generally (or, in another variant, after their ships -- this would also allow us to tip our cap to Beagle 2). One advantage of this is that there have been many explorers from all lands, so we could easily give the names an international flavor. (And we could include Darwin in the honorees, which is a big plus as far as I'm concerned.) A problem with this is that the same explorer is usually perceived differently by different cultures -- Columbus might be the most obvious example (though nobody brought him up explicitly), but for nearly any famous explorer you can think of, there's someone who thinks of him less as an explorer and more as a marauder. The idea was gaining momentum despite this drawback, until our NASA HQ rep said something like "I can just see the name 'Pillager Hills,'" which provoked a lot of laughter and seemed to deflate the proposal.

Other suggestions for geological features: deliberately generic names such as "East Hills" and "South Knob" (derided as "too boring"), names drawn from the coined words in Lewis Carroll's poem "Jabberwocky," and names of general qualities such as "Forbearance" and "Courage." The last proposal fits reasonably nicely with the rover names ("Spirit" and "Opportunity") and lets us preserve "Endurance" as the name for the hills to the east. But I think it might have lost some of its support when someone jokingly suggested "Chastity" as one of the names ("Well, it is going to be a long mission," Squyres laughed).

Yet another proposal that came up late: craters are ring-like, and The Lord of the Rings is popular right now, so why not use Tolkien-based names? A downside is that this might be too topical, but the idea has some support despite that.

Right now, I don't think any proposal is winning. We have to settle on something before too much longer, because our jobs are easier when the features have names, but it's a hard problem: we don't want to be too exclusive (that is, too America-focused), too generic, too topical, or too serious. ("Too serious" is a problem because we don't want the International Astronomical Union to think we're trying to usurp their job of giving these o

News disappearance?

[arfuni]

Is it just me or did the landers totally disappear from all major news sources? I haven't caught mention of them on CNN, BBC and the like in quite a while. Did the government stop spending the money on press releases when they failed to take heat off of the administration and/or capture public attention?

Re:News disappearance?

[pease1]

There was little question this would happen... if you watched the daily news briefings for the two weeks after the landings, each day there were fewer and fewer reporters in the room.

The rovers quickly became "old" news for most editors. How many pictures of rocks and sand dunes can the average public handle? Niche writers - the hardcore science writers - could be handled one on one. No doubt travel budgets were a factor. Even /. stopped covering it.

Besides, the daily press briefings were likely a real time sink for the rover teams, getting ready, attending and following up on the questions.

Besides, when the briefings stopped and the daily news articles stopped, the real science could start. The really great thing is while 15 years ago, we could have never followed what was happening day-to-day, these days, all you had to do was check the rover website.

But, I bet we see a flurry of articles Thursday/Friday as they release the color images of Endurance. But just for the day. Perhaps some more when Opportunity dives into the crater.

Re:Don't jump to conclusions...

[SEWilco]

The rovers have a suspension system which reduces side-to-side tilt. So if a rover is sideways on a slope, wheels on one side can be higher than those on the other side, while the body is more level than the angle of the slope.

The rovers can reduce the angle of a slope by going diagonally up a slope. In a conical crater, a rover could traverse the sides in a spiral pattern to reach the top. Assuming it doesn't slip down as much as it is trying to move up.

The safest route is straight up and straight down. A roll over is more likely when going sideways on a slope.

Harakiri

[photonic]

From the article:

"The big question is, if we can get down, can we get back out?" Wallace said.

If you look at the driving plan thus far and at the surroundings, you see that endurance crater is pretty much the only big interesting feature in the area. Also, given the finite life of the rovers (extended design life is 180 days?) there must come an end some time. The rovers seem to operate perfectly right now, but i believe that the thermal cycling of the batteries is a definite show-stopper in a couple of months. Considering this, i think it is a fair gamble to drive into the crater with the risk of never coming out. If you do you might get some very interesting data on all the deep soil layers. By the time you would get out you are almost dead anyhow.

Re:Forever, or until the solar panels die...

[hanssprudel]

You could always just (as I presume they will) slowly restrict operations as effeciencies wear down. (Nah, stay here today, charge batteries for a trip tomorrow)

The problem is that at some point the panels are not generating enough energy to keep the rovers hot over night, so the internal temperature of the components cannot be maintained at their operational level, and then NASA expects that they will start having component failures.

This looks familiar.....

[cixelsyd]

Am I the only one who thinks this "crater" looks like a giant antlion trap? Especially with the loose "sand" looking stuff in the bottom center... I could totally see a gigantic martian antlion reaching out of that thing and rending poor opportunity into bits. Let's hope they didn't neglect to include phasers when designing these rovers =)