Opportunity Route Map Options

[CosmicRocker]

Someone mentioned in the Spirit route map discussion how the official Spirit route maps recently have adopted a similarity to Dilo's, by including an inset of a nearby vertical projection.

Interestingly, I've also noticed a recent change in the Opportunity maps, with those including a shaded area highlighting the larger drifts, similar to Bill's maps.

http://marsrovers.jpl.nasa.gov/mission/tm-...ity-sol630.html

[Bill Harris]

As much as Victoria will produce tremendous data, it should be realized that Victoria is a point along the traverse and not the endpoint. In a geological traverse significant outcrops and major changes in lithology and structure are examined and cataloged. The MER planners are striking, for the most part, a reasonable balance between between making progress and gathering data. I thinbk that Erebus is an important point along the way as we've seen subtle, yet significant, changes in the evaporite and the blueberries. The current stop of Olympia is clearly in the "North Erebus" province, which is likely transitional between the "Erebus Highway and points north" and the Mogollon province.

It would be a shame if Oppy rushed past Mogollon and made good progress towards Victoria. She can break down at any time and we might end up with a few pictures of distant outcrops and a lot of pictures of ripples and drifts and not much more. Maximize the science along the way.

--Bill

[Vladimorka]

And something more - given the vertical profile of the area, it is thought, that the evaporite layers at Victoria are of the same depth as these in Endurance, unlike those at Erebus, which are much higher. So even if Oppy reach Victoria, it can turn out, that there's nothing new in terms of geology (but the pictures will be awesome :-))

[Bill Harris]

Although I/we talk about moving "down section", I'm not 100% sure exactly where we are in the section. We've not been able to look at the evaporite in enough detail to spot marker beds. Victoria, based on the topography, has to expose lower sections in the evaporite unit.

To add to the quandry, there are also possible lateral changes in the evaporite as well as vertical.

--Bill

[dilo]

sol645 update

Attached thumbnail(s)

 

[Toma B]

OPPORTUNITY UPDATE: Opportunity Gains Energy and Hits Four-Mile Mark - sol 641-648, Nov 18, 2005:
Opportunity is healthy. The solar array was apparently cleaned again on sol 638. Average solar array energy is around 720 watt-hours after the cleaning event!

So NASA/JPL guys can you now prleeeease step on it and drive....
It's been so long ago since I last heard word VICTORIA CRATER!!!
START DRIVING PLEASE!!!

[RNeuhaus]

Nope, there are tons of interesting geology science around Mogollon rim.. ..before heading toward to Victoria Crater....

Rodolfo

[Joffan]

I'm... dreaming of an Erebus... Christmas
and several weeks beyond that too
where the views are dreamy
and rocks are creamy
and blue.. berries sparkle like they're new...

[avkillick]

If it is any consolation, every day the rover is alive is a day closer to the arrival at Victoria crater. It's all the same whether that day is spent poking around some interesting rocks or navigating round dunes. The rover is still alive and the plan is to go to Victoria - with some surveys along the way.

At this point in time - after nearly two years with both rovers reasonably healthy, the chances only improve that they will both reach their next medium term goals, "home plate" and Victoria respectively.

Perhaps someone here who is an expert on reliability and failure analysis could back that up with some figures.

So NASA/JPL guys can you now prleeeease step on it and drive....
It's been so long ago since I last heard word VICTORIA CRATER!!!
START DRIVING PLEASE!!!

[tacitus]

At this point in time - after nearly two years with both rovers reasonably healthy, the chances only improve that they will

Perhaps someone here  who is an expert on reliability and failure analysis could back that up with some figures.

Except that Opportunity's batteries only have a finite number of charges in them, so even if nothing catastrophic happens, she will eventually reach the point where her batteries will no longer hold enough charge to operate.

I seem to recall the batteries have about a 1000 cycle lifespan. Is that correct?

[helvick]

seem to recall the batteries have about a 1000 cycle lifespan. Is that correct?

1000 charge cycles is listed in a few places. I believe the design requirement was only 300 cycles but the type selected (happily) seems to be rated for around 1000.

One thing that hasn't been established (as far as I can tell) is whether the loss of the batteries will be completely fatal. Does anyone know what will actually happen when the voltage\charge storage level on the batteries falls below the levels needed for them to actually work? Can the rovers operate on Solar Power alone?

[tacitus]

One thing that hasn't been established (as far as I can tell) is whether the loss of the batteries will be completely fatal. Does anyone know what will actually happen when the voltage\charge storage level on the batteries falls below the levels needed for them to actually work? Can the rovers operate on Solar Power alone?

I asked that same question way back, and I believe the answer I got was no, you need the batteries.

I guess they're not going to fail all at once, so there will be a period of time where there batteries will continue to function but not be able to retain a full charge. But when the time comes, and the writing is on the wall, they will reach a point where the diminishing returns will no longer justify the funding, and the project will be shut down and the rover switched off.

Here's hoping that it happens when she's perched on the edge of Victoria crater after one last panoramic vista.

[Cugel]

I asked that same question way back, and I believe the answer I got was no, you need the batteries.

I guess they're not going to fail all at once, so there will be a period of time where there batteries will continue to function but not be able to retain a full charge. But when the time comes, and the writing is on the wall, they will reach a point where the diminishing returns will no longer justify the funding, and the project will be shut down and the rover switched off.

Here's hoping that it happens when she's perched on the edge of Victoria crater after one last panoramic vista.

I wouldn't worry about the batteries too much. The manufacturer claims that more than 2000 deep cycles are nominal. Besides that there is a 50% redundancy in capacity build in and to be really sure each MER rover has 2 battery packs. Of course they do degrade over time, mainly due to oxidation which increases the internal resistance of the cells. This starts from day #1, which is even prior to launch! (The batteries were used at launch and during cruise) However, the degradation and remaining lifetime of the batteries is predictable and we haven't heard anything about it sofar from the MER team.

[edstrick]

I was quite surprised at Pathfinder dying from battery failure. I never understood or heard why the design used such few-cycle-lifetime batteries.

[Bill Harris]

Here is my initial edition of the Olympia-Mogollon route base map. I've highlighted the known dunes, ripples and sand. This is a small JPEG file; if there is interest, I'll provide a 750K TIF file (no jpg artifacts) for group use.

I've added the "known" sand features and will add more as they are verified-- sometimes the sand here is the same tone as the bedrock. Changes and suggestions are always welcome.

--Bill