Comments on: Spirit Rover in Trouble

By: Eric

Eric — Fri, 14 Nov 2008 23:37:31 +0000

I wonder if the reason they didn't design something to protect from the dust is because they never expected the rovers to last long enough to need said system? I know they expected longer than 90 days, but who expected longer than 300 days?

By: Phil

Phil — Wed, 12 Nov 2008 18:28:35 +0000

I asked about a windshield wiper a few years ago and heard that the reason was that it would add extra weight but what I don't understand is why they don't just instruct the solar panels to partially fold up (as they were during transit to Mars). At some point the panels would be vertical and wouldn't the dust just drop off? They can then reopen them. Maybe it would be dangerous in case there was a problem but if the rover is about to die what's there to lose?

By: Rafael

Rafael — Wed, 12 Nov 2008 15:34:32 +0000

I have the highest admiration for the countless NASA engineers and scientists who put these rovers on Mars and maintain them. However, I've always suspected the 90-day warranty period was very conservative. I've noticed this on other missions as well. I think the space agency does this to allow itself a cushion of protection against failure. If you'd ask these scientists in private most would've admit it was expected for these brave little machines to last at least a martian year. Just my opinion.

By: Steven

Steven — Wed, 12 Nov 2008 11:46:47 +0000

Simple Problem, Simple Solution.

Land some humans on Mars and they can clean the dust off.

By: wayne

wayne — Wed, 12 Nov 2008 09:03:50 +0000

12 months old! Surely there is a more recent image.

By: Nancy Atkinson

Nancy Atkinson — Wed, 12 Nov 2008 05:18:22 +0000

sbuf – The camera is up high (about 5 ft off the ground) on a mast. It can look down and pan around to take a complete 360 of the spacecraft. Mind you, it takes several pictures and lots of downloading to get an image like this one.

By: sbuf

sbuf — Wed, 12 Nov 2008 03:08:59 +0000

how did they managed to snap the picture of spirit?is this computer generated or the real picture?

By: Maxwell

Maxwell — Wed, 12 Nov 2008 01:42:50 +0000

They worked for well beyond the 90 day warranty, and that is simply amazing. Our hats should rightfully be off to all the people that made these missions possible.

…But having said that, we now know to expect more out of small packages. We've also been on mars long enough to have an idea of what it can throw at our machines.
So dust countermeasures (among other things) should become part of the plan on future missions.

By: Thomas

Thomas — Tue, 11 Nov 2008 23:08:26 +0000

"Why they haven't thought of a windshield wiper….?"

I keep hearing this stuff everywhere.

Guys, the MER's were only designed to work for 90 days! They didn't plan, nor need to plan, for a five year mission. If they knew that Spirit would last this long, they probably would have given it something to clean itself with.

Also, RTG's aren't practical on a 90-day mission, so they weren't included.

It's like packing enough food for a week-long vacation, and getting stuck there for a month. You're hungry? Why didn't you bring more food?

By: Victor Sheckels

Victor Sheckels — Tue, 11 Nov 2008 22:52:37 +0000

What I don't understand is how something as dusty as that image above could possibly be using solar power NOW.

By: alandee

alandee — Tue, 11 Nov 2008 21:49:18 +0000

A small fan ?
Anyway, the little chaps are troopers, have served humanity over and above the call, have produced, and continue to produce some stunning pictures, and I for one, as an oldie who will unfortunately never set foot on another planet, think the designers, support crews, engineers and all involved deserve some hearty congratulations for keeping them going this long ! ( Is Spirit the one dragging a wheel ? or s that opportunity ? )

Cheers to the rovers!

By: quantum_flux

quantum_flux — Tue, 11 Nov 2008 21:32:57 +0000

Hopefully they are antifreeze and streak-resistant wipers.

By: edu

edu — Tue, 11 Nov 2008 20:03:15 +0000

I was thinking the same thing.

Why they haven't thought of a windshield wiper….?
If nuclear power technology wasn't an option in the table then,

They could have use some simple fluffy blades or electrostatically ionize the dust over the panel and remove them with a biased negative electrode.

By: Huygens

Huygens — Tue, 11 Nov 2008 19:29:48 +0000

Then I guess the two Viking landing sites are now biohazard zones?

They did not put "wiper blades" on the rovers because that was just one more device that would consume power and ultimately break down. Besides, for a while the dust devils were a nice surprise in cleaning them off.

How much more science can Spirit do anyway even without the dust on it?

By: KG6YRA

KG6YRA — Tue, 11 Nov 2008 17:48:20 +0000

RTGs are becoming smaller, safer, and more efficient, as the next generation of RTG will be installed to the New Mars Science Laboratory.

RTG casings are designed for atmospheric reentry, as the Apollo 13 accident represents an extreme scenario due to the high re-entry velocities of the lunar module returning from cislunar space.

Subsequent investigations have found no increase in the natural background radiation in the area. This accident has served to validate the design of later-generation RTGs as highly safe.

By: Tom

Tom — Tue, 11 Nov 2008 17:37:27 +0000

We need another good dust devil!

By: Silver Thread

Silver Thread — Tue, 11 Nov 2008 16:30:08 +0000

Well, considering they are WAY past their 90 Warranty, I suppose the fact that they have lasted long enough to get DUSTY pretty much kicks ass. It's especially novel that we have a pair of these things up there and they BOTH keep working, The designers could make a killing if they got this sort of result from a standard automobile.

By: Some Guy

Some Guy — Tue, 11 Nov 2008 15:27:27 +0000

i think RTGs might be difficult to build on such a small scale, also if you have an incident on launch of a craft with an RTG, there is the possibility of widespread poisoning within a certain radius of the launch site.

By: Some Guy

Some Guy — Tue, 11 Nov 2008 15:24:58 +0000

really, you'd think an organization that can build two geologists on wheels, land them both on a dusty rock some thirty million miles away, and keep them running over four and a half years past their designed life expectancy would realize that a solar powered machine is going to encounter some dust and maybe build in some counter measures…or not…

By: gammaray

gammaray — Tue, 11 Nov 2008 15:21:59 +0000

Or start sending stuff powered by RTGs.

By: Ruimtepous

Ruimtepous — Tue, 11 Nov 2008 13:08:46 +0000

Where are the wiper blades?

By: Maxwell

Maxwell — Tue, 11 Nov 2008 13:07:35 +0000

Note to NASA: Someone please design some fuzzy windshield wipers for future panels.