[HN Gopher] NASA's Curiosity rover: 3k days on Mars
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NASA's Curiosity rover: 3k days on Mars
Author : ystad
Score : 178 points
Date : 2021-01-09 15:42 UTC (7 hours ago)
(HTM) web link (www.bbc.com)
(TXT) w3m dump (www.bbc.com)
| shadowfaxRodeo wrote:
| That's 3000 martian sols. So ~3090 earth days. 90 days more
| impressive than the headline suggests.
| dmurray wrote:
| 3000 day/night cycles, which are possibly more wearing on the
| equipment than the sheer passage of time.
| messe wrote:
| Probably less so for Curiosity than the other Martian rovers.
| It's powered by an RTG rather than solar panels, so the only
| difference between day and night is the temperature
| fluctuations, which is still significant.
| anoncake wrote:
| Do light fluctuations cause wear on solar panels?
| jccooper wrote:
| Not really, but battery cycles and powering things on and
| off constantly does take a toll.
| madaxe_again wrote:
| Panels wear slowly, but just from being hit by photons,
| blasted by dust, etc. - but that's not the problem -
| batteries are. They don't last forever, and every cycle
| takes a little out of their lifetime.
| monocasa wrote:
| Shoutout to Dr. Kathryn Weiss's great conference talk on
| Curiosity's Flight Software Architecture. I know of at least one
| other high availability robotic system that took a lot of
| inspiration from it.
|
| https://www.youtube.com/watch?v=9jVt5vb68xA
| yig wrote:
| Is there a New Year's Day on Mars?
| mbrubeck wrote:
| Mars scientists have a convention that the year starts at L_s =
| 0deg, which is the vernal equinox in Mars's northern
| hemisphere.
|
| The next Martian new year by this convention starts on Earth
| date 2021-02-07, and lasts through 2022-12-25 (Christmas day!).
| tambeb wrote:
| I recommend the stop motion video of the final two and a half
| minutes of the descent. Even with its low quality I think it's
| absolutely mind boggling because you're seeing the actual event.
|
| https://www.youtube.com/watch?v=lZVUKyFNDik
| lambda_obrien wrote:
| I don't think I've lived in one place that long ever in my life.
| This is some amazing engineering, considering everything I own
| breaks after about 5 years.
| pearjuice wrote:
| Planned obsolescence is also amazing engineering if you think
| about it.
| tokai wrote:
| >considering everything I own breaks after about 5 years.
|
| Brilliant people are working hard to make that happen.
| jrockway wrote:
| What kind of stuff do you guys have that breaks? Sometimes I
| wish my stuff broke so I could upgrade it guilt-free, but it
| just doesn't happen. I have to find some unwilling victim to
| donate it to so it doesn't end up in a landfill.
|
| The only thing I own that's broken in recent memory is this
| duvet cover I bought in 2008 that I've used every night since
| then... it developed some big holes after 13 years and I
| threw it away.
|
| None of my tools, computer parts, furniture, etc. have
| broken. I've honestly never even broken a mobile phone,
| though I have dropped them a couple times.
|
| I agree that computers from 10 years ago kind of suck when
| asked to run modern software. That's not "planned
| obsolescence", that's more like "software engineers made more
| complicated stuff more quickly; the downside is that you need
| a new $300 CPU instead of a decade-old $300 CPU". I'm okay
| with that.
| peter303 wrote:
| Several years back NASA issued a warning on the slow progress of
| this mission. Their main objective was to traverse the
| sedimentary layers up Mt. Sharp. They havent really begun the
| climb yet. A long, dangerous sand dune caused a couple year
| delay. Plus lots of investigative stops along the way.
|
| The power will last 20 years. The wheels are damaged from being
| too thin. If funding becomes tight, other missions will have
| precedence.
|
| https://www.washingtonpost.com/news/speaking-of-science/wp/2...
| trestenhortz wrote:
| This book is written by Steven Squyres, the principal
| investigator of the Mars Exploration Rover Mission.
|
| I got at as a Christmas present and didn't expect much but it
| turned out to be one of the best books I have read:
|
| https://www.amazon.com.au/Roving-Mars-Steve-Squyres/dp/14013...
| mabbo wrote:
| It still blows my mind how they landed that rover on Mars.
|
| Heat shield to use the atmosphere to aerobreak. Then it opened
| the largest hypersonic parachute ever to slow it down further
| (dropping the heat shield after it opened). Then eventually it
| cut off the parachute, turned on rockets, and flew sideways so
| that it didn't run back into the parachute. THEN, to avoid
| spitting up too much dust during landing, it lowered the rover on
| a 21 foot tether down to the surface, while hovering above it,
| before flying away to crash somewhere safe.[0]
|
| It's so ridiculous you'd think it came from a movie. And it
| worked.
|
| [0]https://en.wikipedia.org/wiki/File:Curiosity%27s_Seven_Minut..
| .
| D13Fd wrote:
| I found the wheel problems with Curiosity to be super
| interesting. They designed this incredible vehicle, and landed
| it in this incredible way, but making the wheels just a tiny
| bit too thin (in a well-justified pursuit of optimization)
| wound up limiting the scope of the mission when met with
| unexpected terrain. It shows just how small of a margin of
| error they have in making this all work.
| proactivesvcs wrote:
| I think it was Curiosity's wheel treads which spelled out
| "JPL" in Morse. Such a gloriously geeky Easter egg!
| SkyMarshal wrote:
| It's really amazing work, and the knowledge and skills NASA and
| collaborators learned from doing that are invaluable.
|
| I honestly think for the next decade or two that NASA should
| double down on propulsion science, energy science, and
| robotics. Instead of trying to send a few men and biospheres to
| Mars, lets send a greater quantity of increasingly advanced
| robots/AI on increasingly challenging missions to study Mars
| and the Asteroid Belt.
|
| Use NASA's limited budget to advance theoretical and applied
| AI, robotics, and new propulsion/energy generation technologies
| for industrial use in space, with the ultimate goal of creating
| a fully robotic space mining and refining industry and supply
| chain back to Earth.
|
| Keep the ISS of course, as a relatively less expensive way of
| studying the effects of low-G on the human body, space
| agriculture, and human sustainability in space. But for
| anything beyond Earth orbit, let robots prepare the way for
| humanity.
|
| If NASA had an unlimited budget, then by all means do it all.
| But unfortunately that's not the reality right now. The robotic
| missions of the last several decades, from Mars Rovers, to
| Hubble, to probes of asteroids and the outer planets, have had
| such an amazing track record and ROI that they're worth
| doubling down on for the foreseeable future. The rapid advance
| of both AI and robotics is also expanding the mission
| capabilities of this technology, and its worth pushing that
| envelope hard for another decade or two.
|
| Finally, given limited budgets, we can send a greater quantity
| of robotic missions than we can manned missions. Quantity is an
| important factor in quality, as I think the tech world has
| learned in the last decade or two.
| shadowgovt wrote:
| Get hype, because they're doing it again in February. ;)
|
| I believe its name is Perseverance.
| parhamn wrote:
| Great point. In a weird way it makes the whole relanding the
| boosters thing SpaceX did seem like it was obviously within the
| realm of our capabilities if we were ambitious enough. And it
| makes their next goal of 'catching rockets' seem less
| ridiculous too.
| Sharlin wrote:
| It was always within capacity, the question was just whether
| it made sense economically compared to dumb boosters. SpaceX
| was always an extremely-high-stakes gamble that did happen to
| pay off in the end.
| mlyle wrote:
| Yup. There were plans to give the Shuttle flyback boosters
| at various points, but each time it was thought it wouldn't
| pay off.
| bumby wrote:
| Exactly, the DC-X was a reusable design from the early
| 1990s. The feasibility was there, the next hurdle was
| economics.
|
| https://en.m.wikipedia.org/wiki/McDonnell_Douglas_DC-X
| helmholtz wrote:
| If you haven't watched Roving Mars (about Spirit and
| Opportunity), it's a must watch as well.
| jonnycomputer wrote:
| that video is great!
| GeorgeTirebiter wrote:
| https://youtu.be/7gUI18dJx8k
| torpfactory wrote:
| The really crazy part is that they never did a full up
| integrated test of all those systems together and in sequence
| before arriving at Mars.
| wiz21c wrote:
| Those guys have supernatural powers.
|
| Each time I by pass integration tests it _always_ fails at
| the integration points :-)
| asxd wrote:
| Agreed, the amount of validation work that goes into these
| projects must be amazing, and even then the engineers have
| to essentially cross their fingers that no issues were
| missed. I think I'm spoiled in my job in that our software
| can at least be rolled back if we detect an issue after the
| fact (also much lower stakes).
| layoric wrote:
| I was at a local radio telescope for the "live" event when it
| landed. Another crazy part was due to the time delay, by the
| time they were receiving info about entering the Mars
| atmosphere, it was was already over in reality and we all
| just had to wait those "minutes of hell" to find out what had
| happened.
| potency wrote:
| That's incredible, thanks for sharing.
| fireattack wrote:
| It's weird that as a featured media on Commons, no one has
| bothered to add subtitles (YouTube do have them, and the source
| site has transcript too).
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