Mars Rover Races to Survive (APOD 12 Dec 2007)

jimmysnyder · Post by **jimmysnyder** » Wed Dec 12, 2007 12:26 pm

The image is really nice and I'm glad they showed it. However, it has little to do with the explanation. I would like to see where the winter outpost is and the sol when Spirit needs to get there. The projected path would be nice too.

craterchains · Post by **craterchains** » Wed Dec 12, 2007 4:56 pm

From this image, http://antwrp.gsfc.nasa.gov/apod/ap071212.html try clicking on the links.

JohnD · Post by **JohnD** » Wed Dec 12, 2007 6:39 pm

I was wondering the same thing as Jimmie, CC. None of the links answer the question, and unless you are more familiar with the terrain than I, you don't know which way is North. Which way is the APOD view pointing?
One of the links mentions eight weeks in one place as the worst possible case - I thought the wpc was the 'death' of Spirit, as its essential components got too cold to recover.

John

UncleOp · Post by **UncleOp** » Wed Dec 12, 2007 6:41 pm

craterchains wrote:From this image, http://antwrp.gsfc.nasa.gov/apod/ap071212.html try clicking on the links.

I too found the description a little wanting, and did click (or at least hover) the links but didn't see obvious answers to my questions (first sent to the editors, and Robert redirected me here):

Astropix is always a delight. Today's might have been even more helpful had there been either a) a link to a site describing what "sol N" means for the rovers (e.g., http://www.giss.nasa.gov/tools/mars24/help/notes.html), and/or b) something to correlate a given Spirit "sol N" to a Terran date. Specifically, being a space-layman, I can't readily tell if "sol 1376" represents "today (12/12/2007)", some past date, or the target place and date where Spirit wants to be for the Martian winter. Oh, and there's no indication on the image of what Martian "North" is, so it's hard to tell if there's a long or a short way to go.

If your editorial sense and time allow, would you consider adding something to the "Explanation" text to address my questions?

It remains a cool picture; had it been an imagemap that allowed one to zoom in (or hover) to get to extra information - like the correlation of "sol N" to a terran date - it would have been all the cooler. Just my $0.22.

JohnD · Post by **JohnD** » Wed Dec 12, 2007 6:52 pm

Found the latest at http://marsrovers.jpl.nasa.gov/gallery/ ... 1210a.html

The APOD view is Northwards, and this Rover web page shows Spirit's position two days ago, a month after the APOD map. It's nearly there!

But that page also shows the dust problem very clearly!

John

iamlucky13 · Post by **iamlucky13** » Wed Dec 12, 2007 7:06 pm

If you look at this MRO image:

http://marsrovers.jpl.nasa.gov/gallery/ ... ls_br2.jpg

You can see what looks to me like Spirit just 20 pixels or so NNE of the dot labeled "2nd Winter." There's sort of a blue-ish object with a clearly defined shadow right on the edge of the path.

That dust looks pretty serious, but this is how bad they expected it to be 3 years ago when they were designing them.

jimmysnyder · Post by **jimmysnyder** » Wed Dec 12, 2007 9:03 pm

Thanks all for these excellent posts. The images in the site mentioned by JohnD provide most of what I wanted to know. The site said the minimum solar energy days (sols?) come in June 2008. It looks like Spirit has a 35 meter sprint ahead of it. Go Spirit go! I assume it needs to get to where it's going before the minimum. Do you know how much time it has? I would really like to get weekly updates.

Geoff Gaherty · Post by **Geoff Gaherty** » Thu Dec 13, 2007 3:45 am

I'm puzzled by the statement in the caption:

"Earth scientists hope that Spirit can reach a slope on the northern edge of the unusual feature dubbed Home Plate, before the end of this month when northern winter will be phasing in on Mars."

Vernal equinox was on December 10 (Ls = 0°), so spring has just begun in Mars' northern hemisphere. Anyway, Spirit is at Martian latiude 15° S, so surely you should have said _southern_ winter?

iamlucky13 · Post by **iamlucky13** » Thu Dec 13, 2007 6:25 pm

Geoff Gaherty wrote:so surely you should have said _southern_ winter?

Yeah, looks like a typo.

jimmysnyder wrote:I would really like to get weekly updates.

The official mission site has updates at irregular intervals, usually around every two weeks.

http://marsrovers.jpl.nasa.gov/mission/status.html

For help understanding a few things, with a fully charged battery on good terrain the rovers are capable of driving 100-150 meters in a day, although that uses more than a days worth of solar power. The rovers need about 150 Watt-hours per day to keep the electronics box warm. Rated power, IIRC, is 700 Watt-hours per day with a decent sun angle, clean panels, and clear skies. Spirit is currently getting about 310 Watt-hours per day, which doesn't leave a lot to spare for communication with earth and driving.

Opportunity, that ever-lucky robot, recently had a good stiff wind blow some of the dust off its panels and is sitting at a great angle on inside rim of Victoria Crater. It's getting over 630 Watt-hours per day.

BMAONE23 · Post by **BMAONE23** » Thu Dec 13, 2007 6:52 pm

It is amazing just how DUSTY Spirit is right now.

It is tough to tell where the ground ends and the rover begins

starnut · Post by **starnut** » Fri Dec 14, 2007 1:38 am

BMAONE23 wrote:It is amazing just how DUSTY Spirit is right now.

It is tough to tell where the ground ends and the rover begins

Is there a carwash nearby? If not, then the next rover someone sends to Mars should have some way to wipe the dust off as needed. Perhaps a robot housekeeper with a feather duster.

Starship Asterisk*

Mars Rover Races to Survive (APOD 12 Dec 2007)

Mars Rover Races to Survive (APOD 12 Dec 2007)

A little more info would have been helpful