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Spirit - 2010 Winter@Troy, The first stationary science campaign
ElkGroveDan
post Feb 13 2010, 12:06 AM
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The flash memory anomaly is now very well understood and there is a lot of easy to find discussion of it.

The short answer is, no. The programming error that caused the flash memory to fill up was fixed on both rovers once the problem was identified. There is no chance of that particular problem of ever recurring.


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Paolo
post Feb 13 2010, 01:46 PM
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Is there anything published about Spirit's "moment of inertia" experiment? I can't find anything...


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Poolio
post Feb 13 2010, 04:48 PM
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Wow, Doug, thanks for all the relevant info. I will delve into those documents in my copious free time (!), but the quote you highlighted and your follow-on comments were very illuminating.

So the rover does consume a minimal amount of power and the BCB "stays awake" even during hibernation. This also explains questions I had about how the rover wakes up -- what triggers the event that prompts the comm attempt. This must be different from Phoenix who suffered no sunlight and therefore no power for many months. I assume that if you dropped Spirit into the arctic circle at winter, she would become irrevocably dead.

The excerpt also sheds some light on the latest JPL update that talks about adjusting the comm window for the winter. And somehow I never knew that the rovers had RHU's in their bellies.... So there are 8 RHU's generating 1 W each. Winter temps are expected to reach -40C. Does anyone know what the resulting temperature would be in the WEB given these parameters?
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imipak
post Feb 13 2010, 08:20 PM
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When I win the lottery, I'm funding a start-up to develop immortal batteries, capable of surviving months of no charge and then recharging. Oh, and electronic components capable of surviving, say, 200 degree thermal cycles indefinitely. Hopefully there'll be enough left over for Doug's pony, too wink.gif


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briv1016
post Feb 14 2010, 06:55 AM
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There are 801.9 Mb of imagery data and an unknown amount of spectroscopy and telemetry data stored in flash. Since flash is volatile memory, will it be cleared if a low power fault is tripped?
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PaulM
post Feb 14 2010, 09:01 AM
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QUOTE (briv1016 @ Feb 14 2010, 06:55 AM) *
There are 801.9 Mb of imagery data and an unknown amount of spectroscopy and telemetry data stored in flash. Since flash is volatile memory, will it be cleared if a low power fault is tripped?

Flash is none-volatile memory. I do not believe that so much data could have built up in Flash if it was volatle. I presume that much of this data predates that last time that Spirit was told to sleep overnight and so would have been cleared if flash was volatile.

I guess that many of these pictures were taken in a search for dust devils and represent frames in which no dust devils were found. dd.gif They may therefore never be returned to Earth.
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briv1016
post Feb 14 2010, 09:28 AM
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My bad. For some reason I thought that the flash memory was volatile. rolleyes.gif
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Explorer1
post Feb 14 2010, 08:23 PM
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Greetings everyone. Longtime lurker here (since the mer.rlproject.com days!) and I finally have a question that I can't find the answer too. Here goes:

The Viking landers lasted for many years on the Martian surface, immobile. Is there some technical reason their comm. data cannot be used for measurements of Mars's interior, like the long-term plans are for Spirit? I'm just asking because I find it hard to believe that no one would use that 30+ year old data to do the same things we're doing now. There must be some good reason they can't be used.

Thanks, and keep up the good work keeping this place great! smile.gif
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djellison
post Feb 14 2010, 08:48 PM
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MI Pan now she's parked up. Others will do a far better job of sharpening these images up smile.gif
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sgendreau
post Feb 14 2010, 09:25 PM
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QUOTE (Explorer1 @ Feb 14 2010, 12:23 PM) *
The Viking landers lasted for many years on the Martian surface, immobile. Is there some technical reason their comm. data cannot be used for measurements of Mars's interior, like the long-term plans are for Spirit?


I believe Squyres said in one of his interviews that the Vikings did not collect the appropriate type of data. Sorry, no link.
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Eluchil
post Feb 14 2010, 10:14 PM
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QUOTE (Explorer1 @ Feb 14 2010, 08:23 PM) *
The Viking landers lasted for many years on the Martian surface, immobile. Is there some technical reason their comm. data cannot be used for measurements of Mars's interior, like the long-term plans are for Spirit?


My understanding of the experiment is that what they will be looking at is the DSN tracking data rather than anything generated on-board Spirit herself. Thus, we'd have to look to upgrades to the DSN or improved knowledge of Earth's rotation and orbit for the explanation. It's a good question though.

Eluchil
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elakdawalla
post Feb 14 2010, 10:36 PM
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I asked Squyres about past landers during the January press briefing (when prodded to by Doug!). He said that the Viking radio system wasn't the right type to permit the precise tracking required. They had S-band radio, the rovers use X-band. I think that's the reason. They did do tracking with Pathfinder, but the mission didn't last long enough.

--Emily


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Explorer1
post Feb 14 2010, 10:51 PM
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Well that explains it. Thanks for the quick reply! Hopefully Spirit will last long enough to be able to do this.
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ddeerrff
post Feb 15 2010, 02:59 AM
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QUOTE (elakdawalla @ Feb 14 2010, 04:36 PM) *
wasn't the right type to permit the precise tracking required. They had S-band radio, the rovers use X-band.


Are they making some of the new measurement using Doppler? Perhaps the Viking S-band radios didn't have sufficient frequency stability.
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elakdawalla
post Feb 15 2010, 03:46 AM
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That would make sense. I don't know, though.


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