Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission • Hacker News Board

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#201

Post by fma » Thu, Feb 14, 2019, 12:15 PM UTC

HALtheWise wrote: post #154

slg wrote: post #23

Opportunity's and Spirit's original missions were planned to last 90 Martian days each. They ended up lasting over 8,000 combined. That is almost as impressive as getting the rovers to Mars in the first place.

JPL wrote a fascinating reflection on what engineering practices allowed this to happen. For any of you who have not experienced the NASA Knowledge Gateway, I would recommend. https://llis.nasa.gov/lesson/1743

Nice concise read. I think many lessons are well known but not acknowledged. For a high quality product...Test a lot, experienced people, do things in house.

Meanwhile software industry is... Ship to prod ASAP, hire junior devs to reach head count, outsource to overseas and contractors.

I realize the risks are different... But management gets pissed when software causes financial lost and wonder why.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#202

Post by presscast » Thu, Feb 14, 2019, 12:19 PM UTC

sidcool wrote: post #199

Timothycquinn wrote: post #81

Earlier quoted context omitted.

Excellent question. I assumed that one mars minute differs from an earth minute but I just learned that they don't. Seconds, minutes and hours are universal. Hours in a day is what varies by planets, moons etc. Funny that I never thought of that before :)

Not if we take gravitational time dilation into account. But for most practical purposes between Earth and Mars, a minute will be the same.

>Not if we take gravitational time dilation into account.

I think most of us will be observing the minute of silence from Earth, either way ;)

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#203

Post by orzig » Thu, Feb 14, 2019, 12:49 PM UTC

fma wrote: post #201

HALtheWise wrote: post #154

Earlier quoted context omitted.

JPL wrote a fascinating reflection on what engineering practices allowed this to happen. For any of you who have not experienced the NASA Knowledge Gateway, I would recommend. https://llis.nasa.gov/lesson/1743

Nice concise read. I think many lessons are well known but not acknowledged. For a high quality product...Test a lot, experienced people, do things in house. Meanwhile software industry is... Ship to prod ASAP, hire junior devs to reach head count, outsource to overseas and contractors. I realize the risks are different... But management gets pissed when software causes financial lost and wonder why.

One systemic problem is that the ownership and management of most companies shifts significantly over a 15 year time span, whereas the people designing a new NASA program know that they (or people that they care about) would be picking up the pieces if they are sloppy.

I wonder whether family owned companies are closer to NASA in their testing/hiring practices?

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#204

Post by icebraining » Thu, Feb 14, 2019, 12:56 PM UTC

Retric wrote: post #159

sramsay wrote: post #137

Earlier quoted context omitted.

Oversold? A group of engineers put a working robot on a moving object 140 million miles away, and that robot trucked along for fourteen years . I honestly do not see any aspect of this which is not totally and completely astonishing, marvelous, and awe-inspiring.

They designed it for a winter which means at least 687+ earth days days was considered achievable. Dust was expected to be a larger issue and in many ways they lucked out, but more so as a calculated risk than blind luck. Distance makes little difference past the first day. Doing the same thing on the moon would not be easier becase it’s closer. It’s local conditions that make this hard more so than simply getting to…

To me, that they designed it to last that long, and it actually did, just makes it more impressive. Otherwise it would just be blind luck.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#205

Post by tomp » Thu, Feb 14, 2019, 1:00 PM UTC

stoops wrote: post #123

Ianworld wrote: post #105

Earlier quoted context omitted.

I remember talking to a high up on the program at a FIRST robotics event who complained about them running so long. They weren't making any major new discoveries and sucking up resources and mindshare stopping him for kicking off and focusing on new projects. He said nobody would take the PR hit to decide to just end a mission like this so he was stuck.

Sounds like that person doesn't really understand that NASA is a political entity and the Public Relations of an ongoing successful mission is more valuable long term than more scientifically pragmatic experiments in the immediate.

Sounds like s/he perfectly understood that, but still didn't like it. Often (always?) politics get in the way of actually getting things done in a smart fast efficient manner.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#206

Post by [deleted] » Thu, Feb 14, 2019, 1:04 PM UTC

JohnJamesRambo wrote: post #140

crushcrashcrush wrote: post #127

Earlier quoted context omitted.

Jesus dude, can’t you enjoy a crowning achievement of human and American excellence? You think NASA is overly concerned about public perception to the tune 44x an original estimate?

I celebrate the achievement just fine, it’s the horrible estimate that is shoved in my face constantly I have issues with. It represents a dumbing down of science for the masses that is just getting worse year after year that I resent. The rover isn’t good enough as is, we are told to be impressed by a nearly 50-fold wrong estimate that is all anyone knows about the rover. I knew it would be one of the top comments o…

[deleted]

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#207

Post by throwaway-hn123 » Thu, Feb 14, 2019, 1:41 PM UTC

droithomme wrote: post #131

Ianworld wrote: post #105

Earlier quoted context omitted.

I remember talking to a high up on the program at a FIRST robotics event who complained about them running so long. They weren't making any major new discoveries and sucking up resources and mindshare stopping him for kicking off and focusing on new projects. He said nobody would take the PR hit to decide to just end a mission like this so he was stuck.

> I remember talking to a high up on the program at a FIRST robotics event who complained about them running so long. Not surprising at all. Coached a FIRST team for several years. At this point they sell licensed robotics kits with canned instructions for kids to put together and those kids win because of time limitations. The teams that build from scratch and actually contribute discover or learn anything at all ar…

> The entire program is total crap for retarded children

Great moderation, dang.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#208

Post by icebraining » Thu, Feb 14, 2019, 1:46 PM UTC

JohnJamesRambo wrote: post #140

crushcrashcrush wrote: post #127

Earlier quoted context omitted.

Jesus dude, can’t you enjoy a crowning achievement of human and American excellence? You think NASA is overly concerned about public perception to the tune 44x an original estimate?

I celebrate the achievement just fine, it’s the horrible estimate that is shoved in my face constantly I have issues with. It represents a dumbing down of science for the masses that is just getting worse year after year that I resent. The rover isn’t good enough as is, we are told to be impressed by a nearly 50-fold wrong estimate that is all anyone knows about the rover. I knew it would be one of the top comments o…

I don't disagree with your overall point, but if you care about accuracy, you shouldn't also conflate an engineering goal with an estimation. I couldn't find the original estimation, but considering the unknowns we're talking about and the sunk costs, surely a 4-8x safety margin (1-2 years estimation) is not unreasonable. So we're at most talking about a 15-fold wrong estimation, not 50.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#209

Post by icebraining » Thu, Feb 14, 2019, 1:48 PM UTC

mehrdadn wrote: post #186

dullgiulio wrote: post #185

Earlier quoted context omitted.

They change the duration of the day, not the minute.

The clock goes from 59:59 to 59:60...

Yeah. Or they smear it over a longer time period, but that still (slightly) extends the duration of each minute.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#210

Post by KallDrexx » Thu, Feb 14, 2019, 1:54 PM UTC

greglindahl wrote: post #161

goatherders wrote: post #160

Earlier quoted context omitted.

I disagree. Even without accounting for expectations, making a machine that works for years without regular scheduled maintenance in extreme conditions is a monumental feat. Ask people who work in the oilfield, extreme heats, extreme humidity, etc.

The discussion is about 90 days, not years. Years is awesome. 90 days was a planning goal used to set engineering priorities.

Kinda/sorta.

90 days was because they didn't think a rover would last over 90 days due to dust storms. They figured that after 90 days they'd encounter a bad dust storm that would cover the solar panels and make them unable to collect power, and thus the battery would be drained and unable to charge after 90 days.

They didn't account that the winds on mars would be able to clean the solar dust off the solar cells so well that it turned out dust storms weren't a huge issue until the latest one.

And from my understanding it wasn't the intensity of the latest storm that killed it but the part of the rover's computer that kept track of time was shot, so it wasn't able to optimize when to go to sleep and when to wake up properly, causing it to run out of charge while it was dark.