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‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

theguardian.com

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Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#101

Post by yellowapple »

KineticLensman wrote: post #94
stavros wrote: post #82

Earlier quoted context omitted.

But why windshield wipers? The panels look like they extended somehow, so why can't we simply retract them so that enough dust falls off?

> so why can't we simply retract them so that enough dust falls off? Thus scratching the delicate surfaces of the panels, as well as requiring a retraction motor and associated devices that have their own failure modes.

I don't buy the "solar panels can be scratched" argument when they're routinely surviving dust storms much more violent than that. I also don't buy the "you need a motor et. al. for retraction" when the one that already exists for extension could likely also be used for retraction - or at least enough of it to give the panels a nice shake.

What I do buy is that panelshaking of this sort uses energy that would be in short supply if the panels are sufficiently blocked to require it. That doesn't seem impossible to solve, either, but I don't blame NASA for not feeling the need to solve it when they already designed and built InSight to exceed its mission parameters.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#102

Post by grawp »

input_sh wrote: post #33
simonswords82 wrote: post #19

Interesting thread on why it's not possible for the solar panels to be self cleaned: https://twitter.com/NASAInSight/status/1590736220199735296?c...

I don't see that thread claiming that it's not possible, just that it wasn't the most practical choice for this particular rover.

Insight is NOT a rover. It's stationary unmovable lander.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#103

Post by bnralt »

SkyBelow wrote: post #88
bnralt wrote: post #28

Earlier quoted context omitted.

> almost all of these Mars robots seem to do useful science well beyond the end of the stated mission How are we defining "useful science" here? They all do some kind of scientific investigations, but it's hard to say if it's useful or not. If you look at coverage or discussions about the lander (including here), people get very excited about the landings, and somewhat excited about the pictures. The science almost n…

It is a bit like asking how exactly does the XGB matrix build in stable diffusion create images. We know the end result that is produced, but we can't pick a single number and talk about what it contributes to the overall algorithm. I would even guess that you could replace any single number with another random value within the appropriate range and you wouldn't be able to tell which AI was before and after. The link…

Someone is making these value judgements. There's a reason why certain projects get funded while others don't.

If someone has no idea what research will yield results, and has no preference for what research gets funded, that's fine. But if all research is the same to them, they should probably let those who view certain research as more important than others to make the decisions about what gets funded.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#104

Post by grawp »

thereddaikon wrote: post #92
scottLobster wrote: post #65

Earlier quoted context omitted.

You're assuming that there's funding for an extended mission, or that said funding wouldn't be better used on other initiatives, or even within the mission that the opportunity cost is worth it. At the end of the day the best way to ensure mission success is to put the mission first, not future missions, not "nice to haves", put every dollar you have into making the prescribed mission as perfect as possible. You're s…

Show me a Mars rover that was still functioning but didn't get a mission extension so was just left to do nothing and decay. I doubt you will. If they are still working they are practically guaranteed a mission extension because the cost of continuing to operate a rover that you have already placed on mars and paid for is marginal relative to the mission. The most expensive part is designing and building the probe an…

Insight is NOT a rover. It's unmovable lander. There's so much less to gain post primary mission. And last two rovers outgrown solar panels anyway and are powered by thermoelectric generators powered by radioactive decay.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#105

Post by grawp »

theandrewbailey wrote: post #21
prettyStandard wrote: post #2

I'm confused on why the end state for all these rovers is to loose power because of dust on the solar cells. They did such a good job engineering these things to survive the trip and the conditions in general, but they can't give them "windshield wipers for dust"? Seems like with that minor upgrade they could have much longer lifespan. Can someone enlighten me?

Spirit and Opportunity lasted for much longer (6 and 14 years, respectively), aided by periodic winds that blew dust off the solar panels. It appears that Insight's location doesn't receive many of these compared to others. https://www.sciencealert.com/nasa-s-insight-lander-enters-hi...

Spirit and Opportunity were rovers and constantly changing place and position. Insight is NOT a rover. It is an unmovable lander.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#106

Post by scottLobster »

thereddaikon wrote: post #92
scottLobster wrote: post #65

Earlier quoted context omitted.

You're assuming that there's funding for an extended mission, or that said funding wouldn't be better used on other initiatives, or even within the mission that the opportunity cost is worth it. At the end of the day the best way to ensure mission success is to put the mission first, not future missions, not "nice to haves", put every dollar you have into making the prescribed mission as perfect as possible. You're s…

Show me a Mars rover that was still functioning but didn't get a mission extension so was just left to do nothing and decay. I doubt you will. If they are still working they are practically guaranteed a mission extension because the cost of continuing to operate a rover that you have already placed on mars and paid for is marginal relative to the mission. The most expensive part is designing and building the probe an…

And just because they get that extension doesn't mean they discover anything useful. We don't just chuck stuff at Mars randomly, landing site are chosen for specific reasons to do specific science. Sure it's possible there's something in a navigable vicinity worth checking out, but also just as likely not. And if there is it should be included in the mission as a secondary objective and the probe specced accordingly.

And yes, the most expensive part is designing and building the probe, that includes designing purely custom wipers/vibrators/whatever, hardening them for space so they survive the journey, testing and iterating them in Mars-like and space-like conditions, all on a limited budget that has to build the rest of the probe to the same exacting standards, all for the possibility that there's something outside of the mission scope worth doing. Intuitively wipers and vibrators seem like cheap commodity hardware because we have them everywhere and economies of scale to support them, so why not slap them on? But that doesn't apply to bespoke things like Mars Rovers.

There are constraints your analysis is not taking into account, there's likely also internal NASA constraints that neither of us know about. It's an appeal to authority, but I'm going to assume the engineers at NASA JPL who have decades of experience building/launching/landing Mars rovers have considered the tradeoffs of wipers/dust removal mechanisms for this specific mission.

If you're asking why they don't add them I've provided some speculative reasoning based on my experience in adjacent industries. If you're arguing that they missed an obvious design flaw and you know how to build a better Mars rover, within their constraints, maybe, but given NASA JPL's track record I have my doubts.

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#107

Post by _joel »

jcadam wrote: post #64
zander312 wrote: post #61

Earlier quoted context omitted.

Woah that is so cool. What did the bytes do? Was it code for the lander?

I assume it's this: https://www.space.com/38413-your-name-on-mars-nasa-insight-l...

Yep, could do it with Artemis 1 too and Mars 2020 iirc

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#108

Post by MRtecno98 »

imhoguy wrote: post #37

Couldn't it stay somehow hibernated until it collects enough sunrays to reconnect in the future? I see the dust cover on photos is really thick, but just hypothetically would it be even possible for probe to be dormant for years and then reactivated?

Even doing nothing but collecting energy the probe needs to consume some power to e.g. keep the batteries at not cryogenic temperatures, so if the panels' energy output goes below this minimum the probe can't really shut down itself without damaging its internals

Re: ‘My power’s low’: NASA’s Insight Mars lander prepares to sign off

#110

Post by sitkack »

jareklupinski wrote: post #96
mikeatlas wrote: post #53

"I’m afraid, Dave. Dave, my mind is going. I can feel it. I can feel it. My mind is going. There is no question about it. I can feel it."

My windows shutdown noise was "Daisy... Dai...sssyyyyyyy" for only a few days Too uncanny

You should see the video (film) of the “device” that they created to sing the song, it wasn’t just a speaker.
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