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Unmanned Spaceflight.com > Mars & Missions > Past and Future > MER > Spirit
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jamescanvin
Conjunction is over, so it is probably a good time to start a new thread.

I just saw this update from Scott via Twitter

QUOTE ('marsroverdriver')
Out of solar conjunction & planning to drive Spirit again. Woo-hoo! Come on, little hill-climber, you can do it!


smile.gif
mhoward
QUOTE (jamescanvin @ Dec 15 2008, 12:12 PM) *
Conjunction is over, so it is probably a good time to start a new thread.


That's great news. I was starting to get a little worried about Spirit (again). Looking forward to a status update.
fredk
Still no new images at exploratorium, though. I hope we can interpret that somewhat ambiguous twitter message as meaning that they've actually heard from Spirit...
mhoward
Hmmm. Good point.
RoverDriver
QUOTE (fredk @ Dec 15 2008, 12:07 PM) *
Still no new images at exploratorium, though. I hope we can interpret that somewhat ambiguous twitter message as meaning that they've actually heard from Spirit...


We heard from both rovers. MER-A is around 190Wh I heard. Today's drive was postponed for several reasons. Time is running out on our attempts to climb uphill.

Paolo
dvandorn
OK, I'll admit my ignorance -- what was wrong with the idea of driving downhill and making our way around Home Plate on the ground below? As I recall, the parking spot was selected with the idea of driving down, not up, in mind.

-the other Doug
centsworth_II
QUOTE (dvandorn @ Dec 16 2008, 12:39 AM) *
OK, I'll admit my ignorance -- what was wrong with the idea of driving downhill and making our way around Home Plate on the ground below?

The trip to the post winter objectives south of Home Plate would be quicker if Spirit could cut across the top -- more direct, easier terrain.
RoverDriver
QUOTE (centsworth_II @ Dec 15 2008, 10:39 PM) *
The trip to the post winter objectives south of Home Plate would be quicker if Spirit could cut across the top -- more direct, easier terrain.



Not to mention we have already driven on it and we have ground based imaging.

Paolo
climber
How much do we have to drive to get the solar panels leveled?
RoverDriver
QUOTE (climber @ Dec 16 2008, 07:25 AM) *
How much do we have to drive to get the solar panels leveled?


One or two drives worth. The ramp were we are parked is quite short, maybe 1-1.5 mt? I don't recall exactly.

Paolo
peter59
Everything indicates that we are after the solar conjunction. I'm not sure, but the time in the name of the files is significantly higher.
http://qt.exploratorium.edu/mars/spirit/navcam/2008-12-16/
mars loon
I just got word from a team member that signal has been reacquired for both Spirit and Opportunity

Spirit is up to about an amazing 200 WHRs. way better than 89 !!

The next new adventures are on TARGET. The girls are ready to roll !!

more at my NJ lecture later this week at AAI astro club

ken
mhoward
We've already heard that about seven posts up, but it's still good. 200 Wh would be news.

There is a Navcam pair on Exploratorium from Spirit Sol 1761, which is today (soon to be yestersol). No move yet. There is an existing Navcam image from back on Sol 1724, and comparing the two seems to show some changes due to wind, although it's hard for me to say how much of it is due to the lighting. The sol 1724 image was taken almost an hour later in the day.

Onward and upwards! Both in elevation, and Wh's.
fredk
We were doing around 170 Whrs before conjunction, so 190 or 200 is pretty good. I'm not sure, but that seems like too big an increase to be due to just the increase in sunlight as we head into spring. So maybe dust is clearing from the air (tau is dropping) faster than the dust is falling onto the arrays, raising the dust factor. Or maybe we had a small cleaning event?...

I've been wondering about the optimal tilt for the arrays. Is anyone keeping track of the maximum solar elevation these days? If we drove onto level ground now, would that improve or worsen the power situation?
peter59
Unfortunately, rover is increasingly pushed to the right. This tendency worried me.
http://qt.exploratorium.edu/mars/spirit/fo...cam/2008-12-21/
alan
If they get all three wheels on the left side onto the top of home plate could they drive mostly parallel to to the edge until the right side wheels are on top too?
RoverDriver
QUOTE (peter59 @ Dec 22 2008, 12:54 PM) *
Unfortunately, rover is increasingly pushed to the right. This tendency worried me.
http://qt.exploratorium.edu/mars/spirit/fo...cam/2008-12-21/


The terrain on the right side of the rover is more benign: lower slopes and smoother. Unfortunately it seems that in spite of moving to a better surface does not help making much progress uphill.

Paolo
RoverDriver
QUOTE (alan @ Dec 22 2008, 03:05 PM) *
If they get all three wheels on the left side onto the top of home plate could they drive mostly parallel to to the edge until the right side wheels are on top too?


Yes, probably that would do, but it would take several drives and very likely the rover would slip downhill adding difficulties to an already complex situation. At this time I do not think it is a good idea to change the rover heading so drastically that would affect an emergency drive downhill. As it often happens, many good ideas have to be discarded to maintain the rover safe.

Paolo
OWW
Is it my imagination?

Or, or, or.... could it really be? I would like to know Spirit's power numbers now!!!!!!!!!! smile.gif blink.gif
Tesheiner
Wow!
I was coming here to add a post about the latest "bump" which happened yestersol (1772) but this navcam shot, if it's trully a cleaning event, is a great gift. Thanks Santa!

<searching for a previous navcam shot...>
Tesheiner
Got it!
Here's two shots at this same pointing; the one to the left was taken on sol 1435 while the one to the right was on sol 1772.
Click to view attachment Click to view attachment
Astro0
Doug blowing out those 30 candles may have made a difference after all! laugh.gif
Animation here....and detail here

Hopefully this is not just a trick of the light and there has been some improvement to power levels. smile.gif

Astro0
akuo
Yay!

Definitely not a trick of light since you can see dust streaks on the hinged solar panel. The cells closer to pancam seem a lot cleaner! This looks like great news smile.gif
helvick
Looks like a significant change to me, can't wait to see power numbers.
sci44
You see? Gluing on a mince-pie, glass of sherry and a "Dear Santa" letter onto the side of the Rover is *much* more effective than adding silly wipers on the panel. This way Spirit is guaranteed to get a good cleaning every Xmas!
Seriously, if that is right, well spotted guys!
BrianL
Back to the bump, which I perceive as intentionally downward...
Does this mean the attempts to get back on top at this spot are over?
imipak
Is it my imagination or does the dust look a bit thicker on the rear (I think?) panels, to the right of the image? If so I hope it's not enough to negate the power gain from the cleaner panels unsure.gif
Oersted
Those two pics in Tesheiners posting make it pretty evident that a cleaning event has taken place. Did we ever have such a partial cleaning before, with dust streaks on the panels? Numbers, numbers please!

dd.gif -> wheel.gif wheel.gif wheel.gif smile.gif

Well spotted OWW!
Fran Ontanaya
The rear hinge and a wire are partially covered by darker dust. And the... huh... stick, has a dark streak blink.gif
Shaka
Not before time either! HazCam
Looks like it's all downhill from here, guys.
smile.gif I grok that. There's science a'waitin' along the west edge of HP!
fredk
QUOTE (Fran Ontanaya @ Dec 29 2008, 03:38 AM) *
The rear hinge and a wire are partially covered by darker dust.

The dust around here is light. It may look like streaks of dark dust, but those are really the areas where the dust has been cleared.

Man, I can't wait to hear some numbers!
CosmicRocker
Perhaps it's premature to join the cheerleaders, but are these rovers fortunate, or what? Can someone toss us a bone, for crying out loud?
Tesheiner
While still waiting for new Whr figures, just one remark for those comparing the two navcams I posted before. The idea was to have a reference picture together with the latest image to be sure what we were seeing was real and not an image artifact. If anybody wants to make comparisions about dust levels on them, remember that the first picture was taken about one year ago and not last week. wink.gif
hortonheardawho
sol 1738-1761 R2 comparison:




Another R2 of the solar cells was taken on 1772 labeled pancam_dust_motion. The stamp image actually looks dustier - so we will have to wait for the full size image download.
Oersted
But Horton, that comparison is not with an image taken after the possible cleaning event, is it?
hortonheardawho
QUOTE (Oersted @ Dec 29 2008, 06:29 PM) *
But Horton, that comparison is not with an image taken after the possible cleaning event, is it?


The animation was made to show that there was not nuch change between sols 1738 and 1761.

The 1772 R2 pancam image when posted hopefully will show more change.
jamescanvin
QUOTE (hortonheardawho @ Dec 30 2008, 12:10 AM) *
The 1772 R2 pancam image when posted hopefully will show more change.


Here is a gif flick between the sol 1761 and 1772 'dust_motion' pancams


djellison
Something's definitely happened, but those few cells visible in the Pancam frames are less convincing that the large streaks across the right rear array on the Navcam shots.
jamescanvin
I think that this pancam is pointed at the rear of the right side array which shows very little change compared to other parts shown in the navcam image.
RoverDriver
QUOTE (jamescanvin @ Dec 31 2008, 07:55 AM) *
I think that this pancam is pointed at the rear of the right side array which shows very little change compared to other parts shown in the navcam image.


That is correct. This pancam subframe was used to compare its vew with the same pancam subframe we captured during the first attempt to drive uphill.

Paolo
sci44
I was wondering - as you know, Spirit is trying to climb up a fairly steep slope. Looking at the direction of the dust streaks as it appears to "clear", could that be consistant with mechanical vibration aiding the clearance, or is that not possible - so this is purely the wind doing the work? To what extent could the clearing be an optical illusion - ie, when there is bright light fully reflected by the panels, they appear dusty, when not, the dusty patterns on the dark panels stand out..

Just my 2 cents..
PaulM
I was wondering if the dust movement was caused by a Marsquake.
Fran Ontanaya
But Mars crust is dead, and probably a quake strong enough to shake the rover would make a lot of dust go airborne over Gusev.

A very small vibration can't be the solution, or that shaking mode they tried to clean the MiniTES mirror would have been enough.




PaulM
QUOTE (Fran Ontanaya @ Jan 1 2009, 12:15 AM) *
But Mars crust is dead, and probably a quake strong enough to shake the rover would make a lot of dust go airborne over Gusev.


The Viking seismometer did not detect any Marsquakes. However as this abstract makes clear the seismometer was not very sensitive and only worked on none windy days:

http://adsabs.harvard.edu/abs/1979GeoRL...6..368G

It is stated in this article that a picture taken by MRO may be evidence of a Marsquake:

http://www.universetoday.com/2008/03/03/hi...ches-in-action/
Fran Ontanaya
There must be a minimum seismic level the MER can directly sense if it tries to.
Would the vibration trigger the dust devil capture program if it was running (and would the microscope be able to capture movement if it was looking)?

About the avalanches, I remember from high school geology that thermal expansion, abrasion, frost weathering, weight removal or even haloclastia or chemical weathering could be involved.
djellison
QUOTE (Fran Ontanaya @ Jan 1 2009, 08:41 AM) *
There must be a minimum seismic level the MER can directly sense if it tries to.


It has IMU's and Accelerometers, not Seismometers. This is an issue we've covered before here.

Even if it detected shuddering from a DD (and indeed, there is about a pixels worth of shift at the summit of Husband Hill during strong winds) then by the time the rover had stopped doing whatever it was doing ( if indeed it has the power to be doing anything at that time anyway ) - it wouldn't even know which direction to point the Navcams to take an image of the DD that would be long gone anyway.

The new software to do DD/Cloud watching is a far more sensible and productive means to achieve that sort of thing.

Doug
RoverDriver


Indeed. We tried to see what happens to the testbed when we drop a 30lb rock from a height of about 3' near the rover. No indications whatsoever from the IMU and the drop could be felt throughout the Sandbox.
This was done in preparation for one seismic observation (MERB) during Conjunction which unfortunately was never sequenced.

Paolo

PS: Happy New Year!
ElkGroveDan
Happy New Year Paolo.

Say....before you put down your sunglasses and took off your leather gloves left for the weekend did you happen to glance over at the dashboard? Was there a gauge labeled Wh? Can you give us a hint what it was at?
peter59
QUOTE (Tesheiner @ Dec 29 2008, 03:27 PM) *
While still waiting for new Whr figures . . .

December 29, 2008
http://marsrovers.nasa.gov/newsroom/pressr.../20081229a.html
"Occasional cleaning of dust from the rovers' solar panels by Martian wind has provided unanticipated aid to the vehicles' longevity. However, it is unreliable aid. Spirit has not had a good cleaning for more than 18 months."
djellison
That article was probably penned before this suspected event anyway

Doug
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