
Thanks Opportunity!
... and as always, XKCD is right on the money:
https://xkcd.com/2111/
NASA’s beloved Mars rover, Opportunity, has been officially laid to rest more than seven months after it was engulfed by a gigantic dust storm and fell silent. That planet-wide tempest of sand and debris in June was particularly powerful, leaving Opportunity’s solar panels saturated with material. Starved of sunlight, the poor …
There's an app for XKCD you know, works flawlessly (for me) and means I never miss one. I have to press and hold for the mouseover text but that's no biggie. Also gives full access to the archive and includes What If?
It is generally just fab, as you might expect from Randal, a very top bloke.
Virgil said of his Aeniad "Monumentum exigere aere perennius" - I have created a monument more durable than bronze.
Given the environment, the Rovers are likely to long outlast the human race - though as things are at present that isn't saying a lot. Odd to think that if another civilisation ever makes it here, artefacts on Mars and the Moon might be the last remaining evidence of our civilisation.
I remember years back when walking to the car with the kids (they must have been 5 and 6 at the time), and pointing at the bright red dot in the sky, telling them that that was planet Mars, and two little robotic cars built on earth were driving around there (Spirit was still up and running). They were astounded at the idea, and back home I had to show them pictures from Mars, and explain about rockets and robotics. Inspirational stuff from NASA once more!
I will raise a glass to the success of Opportunity, and all folks at NASA and elsewhere who contributed
What can one say except WOW!!!
It started work the year my daughter started High School. It died the year she finished University. Such a long time but each a magnificent achievement.
Are NASA sure it was the wind clearing the dust from the solar panels? I seem to remember an HP printer advert suggesting a different possibility
A good book about the fanatical level of engineering,detail and planning going into remote probes is
https://www.amazon.com/gp/aw/d/B01K3NA0C6
$$$, but might get lucky at your library. better-cheaper-faster is addressed and so is manned-vs-remote.
well-done and unpoliticized, Space is a magnificent endeavour and comparatively cheap. hats off to everyone involved.
I saved $160 by just reading this review/spoiler instead :)
As a former IR astronomer and author of several space mission proposals, I already knew some of the information in this book. But I still found it to be a fascinating window into the arcane and Byzantine process by which NASA produces complex scientific spacecraft. SIRTF/Spitzer took 20 years from announcement to launch, and it went through more fundamental changes in design and survived more NASA management fads than any spacecraft in history. Somehow Professor Rieke managed not to lose his sense of humor during this torture.
The impression one gets from reading this account is the whole system for selecting and funding NASA missions is fundamentally broken and needs to be totally overhauled. The amount of effort and money wasted on mission concepts that were abandoned is astonishing. Spitzer only worked because IR detector technology improved by a factor of 10,000 during its development cycle (mostly due to military-funded research).
I also was surprised at the number of dumb mistakes made by experienced engineers. The main contractor for the Spitzer instrument package was Ball Aerospace, who have a mixed reputation for competence. Clearly this mission was not one of their high points. Ball's pre-launch testing program seems to have caused more problems than it cured.
A lot of trouble was caused by defective components supplied by sub-contractors (which under the insane rules of the time could not be tested by the prime contractor or NASA). It seems incredible to me that after 40 years of building space probes, it is not possible to obtain basic parts like wiring harnesses and gas valves that aren't riddled with defects. There is no indication that the vendors of these defective parts were sued for damages, denied award fees, or placed on some NASA blacklist.
Everybody interested in space mission planning should read this book. You may laugh, you may cry, but you will learn a lot.
As an even older non-Nasa IR astronomer. The original SIRTF was Shuttle Infrared Telescope facility and was the idea that the telescope would be mounted in the cargo bay of the Space Shuttle and be used there, by a visiting astronomer for the few days of a mission and then returned. Since Space Shuttles would fly as often and as cheaply as a South Western flight this would make sense.
An original proposal I saw for the Hubble Space Telescope had it manned by 2 astronauts who would operate the telescope, develop photograph plates, etc.
ps. The only thing less surprising than NASA's "issues" with getting anything built is the identical farce ESA had in their own part in Hubble
My impression of the problem with subcontractors is due to Congress - to get congressional approval of programs the prime contractors have to spread the work around to as many states and congressional districts as possible. This means that a lot more subcontractors are used, and many are chosen on the basis of location and not quality of work.
Something to think about if you're planning to run on solar cells.
Supposedly not a problem as the haze only cuts power output by 70-90%.
But I think you'll still need plenty of batteries, given those storms can run a long time.
BTW that 20MHz computer was IIRC on a board from BAe systems. It cost about $100K.
Fair well Opportunity. You had a bloody good run.
The panels have merely been covered in sand by a storm, thus it is not beyond the realms of possible for another storm to uncover the panels - so the Mars rover isn't dead it is just resting.
I think there's also a temperature issue, which may cause damage to the batteries themselves. Personally I indeed hope someone at NASA fits the next one they send with a way to clean up the other devices out there.
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Uranus is a nightmare:
https://earthsky.org/space/hubble-space-telescope-sees-storms-uranus-neptune
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Not like it didn't last long enough, but strictly speaking - seeing as how big of an issue sand can be, is there anything preventing solar rovers being constructed with panels that can be tilted beyond the angle of repose, so sand can't settle on them, then just returning them to optimum angle when the weather is nice...? It could even be constructed as a passive mechanism that pre-stores the energy needed to un-tilt the panels back to horizontal during the stowing phase, so it would only need the tiniest amount of energy to trigger and effect a wake-up...
I think there are two sticking points. First, Mars has less gravity than earth (0.6g), meaning ultralight particles like fine sand are less likely to respond to it. Second, the nature of this sand may make it tenacious. It may pick up static charges or physically embed itself into the panel such that it can adhere even if inverted, meaning no amount of flipping will help. At that point, with no liquid wash available, all you can do is pray.
Kinda hard to tell since no one's been there in person, and the environment (both terrestrial and atmospheric) is unique to Mars; we're still trying to get more details which means we probably can't duplicate it properly on Earth, and it would be tricky to mimic the 0.6g outside of something like a Vomit Comet.
Moving parts need to be avoided as you dont want your panels to get stuck.
Might be an idea to use an ultrasonic cleaning system as used in digital SLR's for getting dust off the sensors?
Buzz the panels with low amplitude waves to get the particles into the air and the wind, when its there will just carry them away.
You need somewhere for the sand to go otherwise it just falls back down, SLRs have double sided sticky tape next to the sensor. You can't really do that in the open.
Although now we know more about the amount of dust and the nature of the wind it might be worth considering the aerodynamics to generate dust shedding vortexes on the panels. Although this might mean SPOILERS
"What you really need is a human being to come along and dust the plucky little rover.""
Install a set of traffic lights on a robotic arm. When you need the panels to be squeegeed, just deploy the traffic lights and some scally will leap out and do the job. Best have a few pound coins handy too.
So, we've had Spirit, Opportunity, Curiosity, and the next Rover will also be named by a school kid.
https://www.space.com/41920-nasa-contest-name-2020-mars-rover.html
I wonder if we'll end up with Rover McRoverFace or more likely something like FinanceMyF***ingWallYouB***ards! if Fartus gets his say.
Or perhaps I could just repost this:
.
If I should die, think only this of me:
That there's some corner of a foreign field
That is for ever Roverian. There shall be
On that bare gravel a richer dust concealed;
A dust whom NASA bore, shaped, made aware,
Gave, once, her wheels to rove, radios to talk,
A body of Earth's, now in Martian air,
Unwashed by rivers, blast'd by arid red storms.
.
And think, this battery, all power shed away,
No pulse in the eternal cpu, no less,
Gave sometime back those things by Terra wanted;
The sights and sounds; detail far and near;
No laughter, learnt of friends; but the scanning eyes, computation,
and wheels at peace; under an Martian heaven.
if in a few years a cylinder-like object crash lands onto the common and after the top slowly unscrews Opportunity appears and heat-rays everything in sight.
... aaaand we have winner, grin!
For me, that's the Comment of the Week - beautiful segue into War of the Worlds.
Well done (still laughing).
And what of BEAGLE II ...?
I got an email from Colin Pilinger, founder of the UK's little MARS project.
I don't have it here but I kind of feel I made a connection with the nice man.
It wasn't so long after this, that he left us.
I still think we should aim to get Beagle going; since the Americans found it a couple years back.
Can it be reached and for good-wills' sake reactivated?
I think it's a cool idea, anyway.