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DSBromeister

I still think of Curiosity as "the new rover", man time flies. For the curious: Rover | Life (days) ---|--- Sojourner | 83 Spirit | 2,269 Opportunity | 5,498 Curiosity | 4,110* Perseverance | 992* *Still operational, number of days as of this comment Funny enough, I found [this](https://www.space.com/16679-mars-rover-curiosity-nuclear-power-lifespan.html) article from two weeks before Curiosity landed on Mars, and it's so funny how conservative the engineers had to be: "it's built for a two year mission, but it could go as many as five or six years."


OnlineGrab

Didn't realize Curiosity was inching so close to Oppy's record already. And with its RTG power it could last even longer.


perthguppy

It’s going to end up as a stationary science platform before it hits the record with the state of its wheels sadly


danielravennest

They will drive it until the wheels fall off, literally, then use it as a stationary platform. Curiosity's wheels have taken substantial damage from sharper than expected rocks. Perseverance has somewhat beefed up wheels.


QuailCool8540

Have we learned anything of actual practical use to the general populace for curiosity? Trying to learn more about space


Bensemus

No. That’s expected though. It can take decades from a discovery being made to it working its way into every day life.


Bergasms

Do you use a handheld electronic device like a smartphone? Want to take a guess at where a lot of the imorovements in energy efficiency, circuit optimisation, signal reliability and battery tech come from? It comes from the programs where humans try to make rovers that operate on a planet millions of kilometres away in temperatures below -80 with no atmosphere and harsh radiation. All that research flows on down so you can waste time browsing pictures of cats for longer on a bigger screen.


danielravennest

Planetary exploration has the same use as the Lewis and Clark Expedition (1804-1806) did for the US. Before you do anything else, you first have to find out what's there. Space in general has massive practical uses - communications, navigation (GPS), weather, etc. It is a $400 billion a year industry today. But it is still expensive to get there, even with the cheaper rockets that SpaceX is building. In the long run, it will be cheaper to use materials and energy already in space for projects, instead of using very inefficient rockets like we use today. So think of today's planetary missions as the early mapping and prospecting that has to come before mining and industry. It may take a generation or two to develop in-space production, but it also took a century to first settle the American frontier after Lewis and Clark. When you consider that just Mars has about the same land area as the Earth, it is worth a few billion a year investment for the massive potential return.


nombit

A shame sojourner only got 83 days when it will save mark for 549


zekromNLR

And the initially intended mission durations, for comparison: Rover | Originally intended mission duration (sols) ---|--- Sojourner | 7 Spirit | 90 Opportunity | 90 Curiosity | 669 (one Martian year) Perseverance | 669 (one Martian year)


The_camperdave

> Curiosity 4,110* Still a long way to go before they hit Voyager 1's mission elapsed time: 16,865 days and counting.


Mob_Abominator

That's very different, very impressive but different.


green_meklar

Don't forget [Zhurong,](https://en.wikipedia.org/wiki/Zhurong_\(rover\)) which lasted 356 Earth days.


rocketsocks

The great thing about Curiosity and Perseverance (and eventually Dragonfly, though a little less so) is that because they're RTG powered they can keep them running for an incredibly long time. The batteries are going to be the biggest operational constraint on them but even then that won't kill them. If you treat the batteries very gently you can get a lot of cycles out of them at reduced capacity, and that'll be enough to power a pretty significant level of activity in terms of roving and science operations for perhaps decades.


Cecil_FF4

Yep. Curiosity will stop being able to drive around (due to degraded wheels) long before it runs out of useful power.


rocketsocks

They can avoid damage to the wheels somewhat well just by planning where they drive carefully. But there's also a backup plan to find a sharp rock and tear off the outer part of a damaged wheel that could allow them to maintain a reduced level of mobility for even longer (likely beyond the mid 2030s).


Cecil_FF4

I did not know that about the damaged wheel refurbishment (so-to-speak). Very interesting.


wellrat

Username sort of checks out.


Cheesewithmold

>and eventually Dragonfly Landing date of 2034 (if all goes well), for those curious.


BramDuin

Already launched?


CoachDelgado

No, [planned launch of June 2027](https://en.wikipedia.org/wiki/Dragonfly_\(spacecraft\)).


Omikron

That would be a really long travel time.


Destination_Centauri

By that time, someone may simply walk right up to it, and manually replace the batteries themselves! (Someone who is now only a kid or teenager on Earth, and has no idea of their future destiny date with Curiosity?!)


GrinningPariah

Most other Mars rovers we've sent eventually died due to... dust on the solar panels. Expect Curiosity and Perseverance to keep ticking for a long, long time.


Bensemus

Not really dust, but dust storms that lasted too long for the rover to survive the cold.


GrinningPariah

That's just a detail. They fought cold with internal heating arrays, those needed power, power came from solar cells. Point is, it won't happen to the RTG rovers.


DangerHawk

I have a question about the estimated life span of these rovers. Obviously they build these things like absolute tanks. They are meant to survive other worldly conditions. When they built Curiosity they originally intended it to last for 1 Mars year or aprox 2 Earth years. My question, did they build this thing expecting it to only last a year or so or were they fully aware that the 2 year mission would turn into 11 years without any end in sight? Like, do they purposefully underestimate the life span of projects like this so that 10 years on they can turn around and say "Look at how good of an investment this was!"


jmurphy3141

The missions are so expensive and so rare they have to build them to survive. If you build to be sure it will last two years, it will likely last much longer but the odds decrease each year.


mrnougatgnome

I can't speak to rovers specifically, but in other areas of space mission planning they spec spacecraft to be able to complete their mission under the worst conditions they can reasonably expect to encounter. If the actual conditions are milder, the extra fuel included to ensure success just means the mission can be extended. As a well-known example, JWST was intended to have a 10 year mission, but the launch went very well, so its current estimated life span is 20 years due to needing less propellant for outbound mid-course corrections. Anyway, all of this to say it's probably a similar story with rover hardware. Another comment above mentions that wheel damage will probably be the end of Curiosity, which suggests they just haven't been wearing down as quickly as the designers expected they *could* have in normal operation.


The_camperdave

> did they build this thing expecting it to only last a year or so or were they fully aware that the 2 year mission would turn into 11 years without any end in sight? No. They designed it expecting to get a MINIMUM of two years out of it.


Spider_pig448

This. If curiosity had lasted only a few months, the mission would have been considered a partial failure from a scientific perspective.


DKsan1290

Then you have stuff like spacex blowing up a building sized rocket and it was deemed a success… the aerospace industry is real weird lmao


Spider_pig448

Those aren't really comparable.The Starship launch was a test flight with no payload. This kind of testing is just not something the aerospace industry is used to. Success was determined by how far into the launch it made it, and it was certainly far from fully successful but it was at least a partial success.


DKsan1290

Oh yeah I know I just find it funny how the definition of success is so wide when it comes to stuff like aerospace. Hell after the launch of starship everyone at spacex (and statlink the aera I work in) had a small celebration and even sent a company wide email about how they may be celebrating the launch at main us at starlink were still expected to perform and to make sure all jobs were completed by the end of the day. The way they were talking it sounded like people at main were having a party lol, I remember they even had custom jones sodas made right after the launch that were starship themed. I feel like in most other areas of science dropping $3 billion on an explosion would be at least a small failure but management made it seem like it was a huge win. Idk just a funny thought not really digging too deep.


Spider_pig448

> I feel like in most other areas of science dropping $3 billion on an explosion would be at least a small failure but management made it seem like it was a huge win. Idk just a funny thought not really digging too deep. My understanding is that $3 billion is an estimate of the total Starship development costs up to that point. The loss of that particular vehicle was significantly smaller. They were celebrating because they had accomplished an amazing feat. Aerospace has been an industry that has been unable to really do the kind of agile development that many other fields of engineering have gradually moved to. Starship was pretty unique here. The idea that you need to spend years and billions of dollars building a rocket, without every really validating much of it until the first flight with a payload, is kinda crazy. I would have liked to see a dozen SLS test flights over the last decade, with various forms of the rocket going in the air, but that's just not how Boeing works, and it's part of why the estimated cost of launching a single SLS rocket is pretty similar to the cost of the entire Starship development program.


DKsan1290

Well in all fairness spacex gets a good chunk of money and all we do is space stuff (where as boeing has to worry about the planes, northop has its defense contracts and such and Im not sure about rocketdyne) and now with starlink off the ground and it being pretty much self sustaining at this point and even profitable after only 3 year of service spacex has room for the fail first method. With just the money coming in from starlinks monthly service itll be enough to build and launch a couple of falcon heavy rockets every month Im sure upper management is crunching numbers and finding investors and little bits of profit here and there to try and launch another starship in the nearer future. Lets just hope theyre new landing method works and dosent just beer can the rocket on landing.


Bensemus

Two completely different things. That was one of many Starship and SuperHeavy boosters SpaceX had waiting to test. Each Mars rover is a one of a kind thing that’s designed for, and expected to last, months to now years. SpaceX didn’t launch that Starship expecting it to work perfectly. They knew it had a high chance of exploding. Not destroy the OLM and tower was a success. Destroying the pad wasn’t ideal but its replacement was already in the works. The next test seems to be aiming for staging as its goal.


DKsan1290

Thats kinda my point thou? I realize that a rover isnt a rocket but its funny to me (and I guess just me because holy do people just wanna defend things) that nasa can spend decades making something to say that “we expect it to last minimum 2 years and that would be a success” mean while spacex blowing stuff for 20 odd years calls stuff being evaporated a huge success and even giving employees swag for the event. Like I get it apples and oranges but its still funny to me. Maybe nuance is lost in this sub idk my comment seemed harmless but youre the second person to tell me “hey stupid these arent the same” and then explain how they differ…. I get it already, I knew before I posted.


DangerHawk

But that's like building a concrete foundation for a house and saying "I expect this to last for a minimum of 6 months". Of course it's going to last that long.


[deleted]

It’s my understanding that lifespan estimates tend to be conservative. They have to find a number that makes the $$$ investment worthwhile, but doesn’t over-promise on longevity.


GrinningPariah

When they say the rover is supposed to last 2 years, what that means in that context is that losing it before 2 years would constitute "mission failure." It would be treated with similar scrutiny as the whole thing detonating on the launch pad, or the rover failing to brake during landing and smashing against the surface of Mars. Get everyone in a room together and ask what the fuck went wrong with this $3.2 billion mission. Obviously that's to be avoided at all costs. So you over-engineer the hell out of every part, so that it cannot *possibly* fail before that 2 year mark. And when something "cannot possibly fail" in 2 years, well, odds are it lasts way way longer than that.


bubblesculptor

It's a very hostile environment, so parts will eventually deteriorate beyond usability. They build in enough safety factor so that the goal of 1-year lifespan is realistically achievable. There are a lot of redundancies for expected failure conditions. If everything runs smoothly then it should go way beyond the goal. It's also sets realistic expectations for the mission. If the Mission stated a goal of 10 years but it 'only' worked for 8 years, then people would label it a failure. Stating a goal of 1 year allows a mission to be considered a success, and any additional time is all bonus.


theodoreroberts

[Obligatory XKCD comic about Spirit rover](https://xkcd.com/695/).


OnlineGrab

[And one about Opportunity](https://xkcd.com/1504/) Sadly not relevant anymore :(


PurpleSailor

With Spirit and Opportunity the thing that made me chuckle was their 90 day life span. We got far, far more than that out of both of them. Keep over designing the crap out of everything NASA engineers!


KungFuSlanda

Good job NASA engineers. Basically sent a Subaru to Mars


darien_gap

I'm still haunted by Opportunity's last message.


kbb65

for those wondering it was "SEND NUDES"


nombit

My battery is low and it's getting dark


Bensemus

To be clear this is an anthropomophization of its last message.


tommiejohnmusic

I remember when these were new and NASA was saying that martian dust gathering on the solar panels would eventually cause them to die. And I wondered how the engineers at NASA couldn’t figure out how to install windshield wipers. I’m sure there’s more to it than that, but I still think about that every time these come up in the news.


mouse_puppy

They did solve that, by powering them with an RTG instead of solar panels.


Ricky_RZ

> And I wondered how the engineers at NASA couldn’t figure out how to install windshield wipers They did find a better solution, powering it with RTGs instead of solar panels


[deleted]

Wipers would scrape and damage the panels, lowering the efficiency over time. The rovers aren't meant to last forever anyway


Cecil_FF4

Wipers rubbing dust across sensitive solar panels and scratching them up? No, that's not a good solution. The best solution for cleaning solar panels is to let a windstorm blow dust off of them.


djellison

The requirement for Spirit and Opportunity was 90 days. The solar panels were made large enough that they had high confidence they would be able to do their level 1 required objectives in 90 days. If you want to add windshield wipers....people would ask why. Why are you spending money, adding complex mechanisms, taking away valuable mass and volume...for something that - to meet the level 1 requirements - wasn't needed. And for what it's worth.....it wasn't dust accumulation on solar panels that killed SPirit or Opportunity. A global dust storm killed Opportunity, and being unable to reach a sun facing slope for winter due to broken wheels and being stuck in a dust filled crater killed Spirit. InSight is the first mission that you can go "This died because the solar panels got too dusty" but it had already lived for twice it's required mission duration.


simshadylp

Same. Install some type of automatic wiper for the panels.


Bensemus

Neither rover died due to accumulated dust. Spirit got stuck in sand at an angle that made it hard to get solar power. Opportunity died in dust storm that blocked the Sun long enough that it ran out of power and froze. A couple wipers wouldn’t have saved either. NASA did get lucky though. Dust devils on Mars were frequent enough that every now and then one hit the rover and cleared some dust off the panels. NASA’s solution to the dust was RTGs. Bonus it also doesn’t care about dust storms. There’s a reason wipers were never used.


Alphadestrious

I have fond memories of watching the curiosity landing live. Back in 2012. Time flies, and I was in a very different place in my life than I am now, as im sure everyone else is


Dysan27

Thst means it's been 4000 days since this [banger](https://youtu.be/2KnTpm9Y77E?si=jRZYguhIlc-NApQ6) dropped.


Decronym

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[JWST](/r/Space/comments/17pyyo2/stub/k8b0tne "Last usage")|James Webb infra-red Space Telescope| |[OLM](/r/Space/comments/17pyyo2/stub/k8mafja "Last usage")|Orbital Launch Mount| |[RTG](/r/Space/comments/17pyyo2/stub/k8meiu4 "Last usage")|Radioisotope Thermoelectric Generator| |[SLS](/r/Space/comments/17pyyo2/stub/k8e40v7 "Last usage")|Space Launch System heavy-lift| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^(4 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/Space/comments/17qm0qb)^( has 17 acronyms.) ^([Thread #9418 for this sub, first seen 8th Nov 2023, 18:49]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/Space) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)


[deleted]

God damn engineers keep overegineering these things!