Remaining Mer Solar Power Extrapolation, helvick's Power Chart :) Options

[Nirgal]

some time ago, helvick posted the following excellent analysis of the
MER solar power situation as an extrapolation of a diagram showing Watts/hours
against Sols.

http://www.unmannedspaceflight.com/index.p...ype=post&id=580
(originally posted in: http://www.unmannedspaceflight.com/index.p...722&#entry10722)

What makes this chart (let's call it Helvick's Power Chart, HPC so useful, is it's taking into account all relevant factors contributing to the remaining power life time of the rovers: seasonal solar input, gradual attenuation by dust accumulation, and (last not least the "pushing" of the cleaning events.

So here is my suggestion to use this thread/topic for updating this chart
whenever new power figures (watts/hours) and/or new cleaning events are
reported by JPL.

This would be a great way to always get an overview of the best guess of the maximum remaining rover life time (i.e. the limit imposed by the solar power...
which, of course does not take into account failure for other reasons, but would be a nice estimate of the maximum expected lifetime of our little heros

The latest JPL power report

The rover's power team reported a dust-cleaning event on Opportunity between sols 524 and 526. Daily power output from solar panels increased from about 500 watt hours to about 650 watt hours.

underlines the remarkable accuracy of the HPC:
helvick posted the chart on May 18 (aronud Sol 460) predicting the 500 Watts/hour for around Oppy-Sol 540 (note, that the chart shows Spirit-Sols),
which is very well in agreement with the new JPL report !

Now, with 650 Watts at Sol 530 after the cleaning event, the "critical-below-300-Watt-drop" would be deferred from (approx) Sol 680 to Sol 750, in other words:
about 70 extra Sols as a gift from the cleaning event ;-)

[jamescanvin]

Of course, I'm sure Steve is more relaxed about it as time goes on but there is no getting away from the fact that sudden rover death is likely at some point so it's the way they have to work. The trick is not worrying about it! SS did mention today about how it's a hard way to work, making long term plans but making sure you are getting the maximum return day by day given you don't know what will happen tomorrow.

All I was trying to point out was that what with solar panel cleaning events and being able to stuggle on coping with several mechanical failures that at this point an electronic failure is seen (by SS) as the way the rovers will probably die. Thus all these power projections, while interesting probably arn't particuarly relevent to rover lifetimes.

James