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

[simonswords82]

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

[barbazoo]

I dislike the Twitter UX so much, it's not clear to me if the "thread" only contains 2 tweets or if I'm too dumb to navigate this shitshow of a UI. Constantly being bombarded with popups doesn't help the UX either.

[input_sh]

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.

[Communitivity]

I am seeing a lot of comments along the lines of 'windshield wipers?'

Cars were invented in 1886, the first windshield wipers became available for them in 1917, 31 years later. That is...

- in an environment with plenty of water - not near waterless,

- on glass windshields (much less fragile than solar panels),

- where we can physically replace the wipers when needed,

- where we can adjust if they get stuck,

- and where there is much less dust.

If we add 5 years of R&D to overcome each of those obstacles (very optimistic, it's more like 10 well-funded years I suspect), then even optimistically we're looking at 25 years. I suspect we might have a rover with self-cleaning panels, or safe cold-fusion, in 25 years. I don't expect one this decade.

[ilyt]

So its essentially "the system needs to be cheap and light enough to beat bringing more panels"

[superjan]

I asked about that recently in another thread. Besides the argument that you can just make the panels bigger, the dust is also statically charged so it is sticky, and wiping it off is not easy. It is also amusing that we, as programmers, are inclined to suggest adding MOVING PARTS to a system that is not servicable, and that the same problem can be solved just by adding more of an already proven solution. It sounds like this one clever special mitigation that solves a minor problem, but instead brings the system down.

[prettyStandard]

They would rather contribute that cost&weight&complexity to just more solar cells. Got it.

[billfor]

This makes wonder about solar roofs and efficiency over time. For example I don't see anything immediately obvious about how a Tesla Solar Roof might degrade over time due to dust and debris, but it stands to reason that it should. It seems like it should be easier to find this type of information on solar panels given the emphasis.

[wazoox]

It's pretty amazing to think it still works with the panels as covered in dust as they are in the last frame!

[JoeAltmaier]

Cant just use a pad on the arm to rub away at them?

[zackmorris]

I don't buy it. There are so many ways to solve the problem that wouldn't add significant weight, that there must be some ulterior motive. And there is.

NASA plans obsolescence into the rovers to get funding to build the next rover.

[photochemsyn]

Given the success of the helicopter drone (Ingenuity) on Mars, I wonder if that's an option for cleaning solar panels - i.e. put a simple rotating brush/fan system on the drone, keep it in a port on the main lander, and every once in a while, launch it and have it land on the solar panels, where it does a roomba routine.

Since drones already expand the abilities of a lander, i.e. exploring the immediate area and collecting samples, this wouldn't be much of an added cost.

[Mistletoe]

Who decided to anthropomorphize the rover like that? It’s creepy and honestly scientifically dishonest, like the rover has intelligence and is writing the posts. Something for children, but children hate being fooled like that and being talked down to. It’s something I might expect from the current version of NASA though.

[MobileVet]

If only there was a simple mechanism, maybe a four bar linkage, with trillions of cycles of testing... it would have to be light weight and include some form of brush or wiper and function with significant forces applied, similar to wind from a moving vehicle...

I guess the downside of having JPL in SoCal is that none of the engineers are familiar with windshield wipers. <jk>

[logicallee]

After reading your note "why it's not possible for the solar panels to be self cleaned" I clicked through and as I clicked I was thinking "okay so obviously it is possible for the solar panels to self-clean. prove me wrong." I mean how hard could it be? No way is that an "impossible" task.

I went out of it thinking, "yep, look at these excuses we are making for the state of robotics." - the quote is: "A system like that would have added cost, mass, and complexity. The simplest, most cost-effective way to meet my goals was to bring solar panels big enough to power my whole mission – which they did (and then some!)."

So robotics is at the state where it is possible to send a rover to Mars, but a simple robotic arm can't easily brush off some dirt. The lander weighs 789 lb and the cost-effective solution is not try include a simple cheap lightweight robot arm that is foolproof and can easily sweep some dirt, because there is not such thing. Robotics isn't at the level where that is easy, cheap, or lightweight.

If a human could reach through a portal to there with a brush, it would take less than five minutes to brush off the dirt that had fallen on solar cells.

A simple, light, and foolproof robotic arm that can easily do that doesn't exist. Now that we have superhuman levels of general AI in chatgpt, isn't it time to work on foolproof and lightweight robot arms for all sorts of tasks?

[devsploit]

I suppose this is kind of a trivial question, but does anyone know if the last message was ACTUALLY the STRING: “My power’s really low. Don’t worry about me though…”, or was it some binary/hex code to represent that, like, "503 ERROR", and the PR department just tweeted its interpretation as “My power’s really low. Don’t worry about me though…”?

It raises more questions. Was this logging message decided by committee or a PM? Was it a dev easter egg? Do they have a writer?

Also, what conditions would trigger this "final" message?

Being a lesser engineer, my stuff just crashes unceremoniously and usually I am alerted not by a sweet note from my prod servers "Hey, looks like prod's going down, don't worry about me, though...", it's usually concerned phone call from a manager.

[kyleyeats]

You're overthinking this. They are literally just quoting the Twitter account which is written in first-person perspective: https://twitter.com/NASAInSight/status/1604955574659035136

[bogantech]

It would have been a data packet containing the battery gauge and some other metrics, it wouldn't make any sense for the lander itself to waste precious bandwidth by spitting out human readable ASCII strings like that.

It's just PR like the last one

[dbg31415]

My guess is that it's PR baked into the software -- at least the receiver software. It was a line written by someone who understood that just an error code is really bad for humans to read. So they humanized it a bit. They had time to plan this, not like they didn't know this was the likely outcome. Good product management to give the robot a voice.

[_joel]

So long Insight! Pleasure having some flash memory that was sent with you, there's a few bytes that have my name in it.

[prettyStandard]

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?

[bamboozled]

Windshield wipers add weight and complexity but more importantly add to the budget.

These things are designed only to serve the mission.

This rover was designed to last 1 year and went for 4 so it’s a pretty good result.

Some good discussion here [1] on Astronomy Cast regarding this topic and potential solutions NASA is working on. Such as an electrostatic dust blaster.

1. https://podcasts.apple.com/vu/podcast/astronomy-cast-ep-661-...

[yummypaint]

I once (around 2010) worked with a nasa designed system for electrically clearing solar panels. It was basically a 3-phase arrangement of transparent indium tin oxide electrodes on the surface of the panels. By supplying high voltage AC, both conductive and insulating particles can be removed by various mechanisms. I thought it worked quite well and keep expecting to see it in the wild somewhere. Maybe it's still in the pipeline somewhere.

[jacquesm]

(1) they were intended to last for three months and (2) dust is extremely static and there is no really good way there to get rid of this static charge, (3) dust is pretty sharp ('abrasive') and will scratch the surface of the cells if removed mechanically.

[theandrewbailey]

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...

[idlewords]

They gave Curiosity and Perserverance a plutonium power source to avoid this issue.

My experience with "why don't they just X" for space stuff is that there's almost always a technical paper on it. This looks like a comprehensive review of different approaches to cleaning solar panels on rovers:

"Cleaning Mechanisms for Solar Panels of Rovers and Other Extraterrestrial Unmanned Vehicles" https://doi.org/10.2514/6.2019-3452

[hawski]

I am sure it comes down to economics really, but I do wonder now about a mission in far future, that would clean solar panels of all those older missions to make them work again. For shits and giggles I guess.

[jvanderbot]

Dust is a factor, but so is cold and diminishing solar. My guess is that the dust isnt a problem until late in the season, and by then they hope to have gotten all the data they came for.

IIRC, one of the reasons the MER rovers lasted so much longer is the dust clearance from wind, which was much more than expected. Perhaps Insight counted on more clearing than they got.

I'd just go ask their Project Scientist on Twitter. @MarkPanning

[Baeocystin]

It costs a lot of time and money simply to keep a mission operating, and these are scarce resources that need to be used for every active mission, old or new. Missions are thus planned for very specific lifetimes. On an organizational level, missions that live too long past their due date cause a lot of problems, too.

This isn't cynicism- it's just the reality of trying to absolutely maximize the science return per scarce dollar spent. I personally would love it if ultimate lifespan was a feasible goal for every mission. So would pretty much everyone! But it isn't.

[rwmj]

Some kind of passive self-cleaning solar-cell cover might work. You could direct and shape the wind so it blows more strongly over the cell surface to clean it, or since the dust is charged[1] you might use a conductive layer with the same charge. (Although I'm sure engineers have thought long and hard about this already.)

[1] Moon, but similar: https://youtu.be/0k9wIsKKgqo?t=378

[arriu]

Same reason the rockets NASA uses are not reusable. It’s not part of the mission.

Yes, it’s short sighted but unfortunately a result of extreme budget constraints.

[mhb]

Oliver Wendell Holmes can (http://holyjoe.org/poetry/holmes1.htm):

The Deacon’s Masterpiece or, the Wonderful "One-hoss Shay": A Logical Story

Have you heard of the wonderful one-hoss shay,

That was built in such a logical way

It ran a hundred years to a day,

And then, of a sudden, it — ah, but stay,

I’ll tell you what happened without delay,

Scaring the parson into fits,

Frightening people out of their wits, —

Have you ever heard of that, I say?

Seventeen hundred and fifty-five.

Georgius Secundus was then alive, —

Snuffy old drone from the German hive.

That was the year when Lisbon-town

Saw the earth open and gulp her down,

And Braddock’s army was done so brown,

Left without a scalp to its crown.

It was on the terrible Earthquake-day

That the Deacon finished the one-hoss shay.

Now in building of chaises, I tell you what,

There is always somewhere a weakest spot, —

In hub, tire, felloe, in spring or thill,

In panel, or crossbar, or floor, or sill,

In screw, bolt, thoroughbrace, — lurking still,

Find it somewhere you must and will, —

Above or below, or within or without, —

And that’s the reason, beyond a doubt,

A chaise breaks down, but doesn’t wear out.

But the Deacon swore (as Deacons do,

With an “I dew vum,” or an “I tell yeou”)

He would build one shay to beat the taown

’N’ the keounty ’n’ all the kentry raoun’;

It should be so built that it couldn’ break daown:

“Fur,” said the Deacon, “’tis mighty plain

Thut the weakes’ place mus’ stan’ the strain;

’N’ the way t’ fix it, uz I maintain,

Is only jest T’ make that place uz strong uz the rest.”

So the Deacon inquired of the village folk

Where he could find the strongest oak,

That couldn’t be split nor bent nor broke, —

That was for spokes and floor and sills;

He sent for lancewood to make the thills;

The crossbars were ash, from the straightest trees,

The panels of white-wood, that cuts like cheese,

But lasts like iron for things like these;

The hubs of logs from the “Settler’s ellum,” —

Last of its timber, — they couldn’t sell ’em,

Never an axe had seen their chips,

And the wedges flew from between their lips,

Their blunt ends frizzled like celery-tips;

Step and prop-iron, bolt and screw,

Spring, tire, axle, and linchpin too,

Steel of the finest, bright and blue;

Thoroughbrace bison-skin, thick and wide;

Boot, top, dasher, from tough old hide

Found in the pit when the tanner died.

That was the way he “put her through.”

“There!” said the Deacon, “naow she’ll dew!”

Do! I tell you, I rather guess

She was a wonder, and nothing less!

Colts grew horses, beards turned gray,

Deacon and deaconess dropped away,

Children and grandchildren — where were they?

But there stood the stout old one-hoss shay

As fresh as on Lisbon-earthquake-day!

EIGHTEEN HUNDRED; — it came and found

The Deacon’s masterpiece strong and sound.

Eighteen hundred increased by ten; —

“Hahnsum kerridge” they called it then.

Eighteen hundred and twenty came; —

Running as usual; much the same.

Thirty and forty at last arrive,

And then come fifty, and FIFTY-FIVE.

Little of all we value here

Wakes on the morn of its hundreth year

Without both feeling and looking queer.

In fact, there’s nothing that keeps its youth,

So far as I know, but a tree and truth.

(This is a moral that runs at large;

Take it. — You’re welcome. — No extra charge.)

FIRST OF NOVEMBER, — the Earthquake-day, —

There are traces of age in the one-hoss shay,

A general flavor of mild decay,

But nothing local, as one may say.

There couldn’t be, — for the Deacon’s art

Had made it so like in every part

That there wasn’t a chance for one to start.

For the wheels were just as strong as the thills,

And the floor was just as strong as the sills,

And the panels just as strong as the floor,

And the whipple-tree neither less nor more,

And the back crossbar as strong as the fore,

And spring and axle and hub encore.

And yet, as a whole, it is past a doubt

In another hour it will be worn out!

First of November, ’Fifty-five!

This morning the parson takes a drive.

Now, small boys, get out of the way!

Here comes the wonderful one-hoss shay,

Drawn by a rat-tailed, ewe-necked bay.

“Huddup!” said the parson. — Off went they.

The parson was working his Sunday’s text, —

Had got to fifthly, and stopped perplexed

At what the — Moses — was coming next.

All at once the horse stood still,

Close by the meet’n’-house on the hill.

First a shiver, and then a thrill,

Then something decidedly like a spill, —

And the parson was sitting upon a rock,

At half past nine by the meet’n-house clock, —

Just the hour of the Earthquake shock!

What do you think the parson found,

When he got up and stared around?

The poor old chaise in a heap or mound,

As if it had been to the mill and ground!

You see, of course, if you’re not a dunce,

How it went to pieces all at once, —

All at once, and nothing first, —

Just as bubbles do when they burst.

End of the wonderful one-hoss shay.

Logic is logic. That’s all I say.

[dctoedt]

Update: NASA has declared the mission over because InSight didn't respond to two successive contact requests.

https://www.nasa.gov/press-release/nasa-retires-insight-mars...

https://www.houstonchronicle.com/news/houston-texas/space/ar...

[mikeatlas]

"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."

[AlbertCory]

This reminds me of the movie Good Night, Oppy

This was a surprisingly touching movie about the Opportunity rover. Yes, it's sentimental, and yes, the NASA crew do call it "her." And yes, the rover does remind you of Wall-E. Still, it's a good flick to watch with the family.

[imhoguy]

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?

[MRtecno98]

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

[kaon123]

Opportunity sent a similar message. Someone on youtube made a phenomenal short video about its life. It is one of my favorite youtube videos ever: https://www.youtube.com/watch?v=FJH9GobEFUk&ab_channel=melod...

[user3939382]

As a programmer my first thought reading this was:

If I was designing a program to send me back a message and it was super critical I received it, I wouldn't put any quotes or non-alphanumerics in the message. Even if my string handling checks out, if the stakes are sufficiently high, I don't trust em!

[thathndude]

I know these are inanimate objects and we shouldn’t humanize them. Blame XKCD, I suppose. But I feel a connection to these robots, and I pray that one day we can go to Mars and erect them a place of honor or bring them “home” to a Smithsonian.

They are a testament to the best of our space programs and the men and women who work in them. It’s amazing how well some of these machines overperformed.

[okdood64]

Great video about Insight, the technical challenges, and findings from it: https://youtu.be/LmkRrtfY6VI

[BooneJS]

Insight and its crew were awesome. I’m anthropomorphizing Insight as Wall-E, diligently fulfilling its mission even as disaster nears.

[slowhand09]

Relevant. https://xkcd.com/695/

[pestatije]

Let Ingenuity fly over it and dust off those panels!

[ColinWright]

Obligatory XKCD: https://xkcd.com/695/