[HN Gopher] India fails to re-establish communication with its M...
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India fails to re-establish communication with its Moon probe
Author : thunderbong
Score : 143 points
Date : 2023-09-23 14:15 UTC (8 hours ago)
(HTM) web link (efe.com)
(TXT) w3m dump (efe.com)
| r721 wrote:
| Kind of off-topic: first time I see a efe.com link, looked it up
| in Wikipedia and surprisingly it's "the world's fourth largest
| wire service after the Associated Press, Reuters, and Agence
| France-Presse ... created in 1939"
|
| https://en.wikipedia.org/wiki/EFE
|
| Just four posts were submitted to HN:
| https://news.ycombinator.com/from?site=efe.com
| pakyr wrote:
| > the major multimedia news agency in the Spanish language
|
| That's probably why.
| [deleted]
| swarnie wrote:
| Seems about right, two English speaking, one French, one
| Spanish.
|
| The legacy of empire.
| rammer wrote:
| Such a loaded headline, almost as though the writers are happy
| that India failed. When the truth is the mission was only
| designed to be for the lunar day and not for the lunar night.
|
| Reeks of jealousy
| AbrahamParangi wrote:
| Why would the authors have any kind of feelings about India
| succeeding or failing?
| tyre wrote:
| India was hoping that the probe could hibernate through the
| night and operate again in the day.
|
| The headline accurately reflects that they're trying to
| communicate with it and failing.
| mehulagrawal wrote:
| If I understand correctly, this was the expected and most likely
| outcome. The planned lifespan of the lander and rover was only 14
| days.
| DylanSp wrote:
| Yep, everyone knew that making it through the lunar night was
| pretty unlikely. A successful landing was always the main goal.
| blackoil wrote:
| Yes, probability of it surviving 14 days in Lunar Night at
| -200C was extremely low. India doesn't have Radioisotope
| batteries that work at this temp. It will also increase the
| payload size and will require larger launch infra. Not to
| mention all the material and chemical challenges faced at these
| temp.
| sidewndr46 wrote:
| That seems like an obvious opportunity for diplomatic and
| scientific outreach and partnership. Did India want this
| project to be entirely homegrown?
| gerdesj wrote:
| "Did India want this project to be entirely homegrown?"
|
| I suspect so and I also think that if you are going to test
| your skills, then being realistic in the first place is
| good idea. The mission was always sold as unlikely to
| survive the night but that would be a nice to have if it
| did.
|
| For me the mission seems to have worked rather well and
| performed exactly as billed.
| dkqmduems wrote:
| Blame Canada.
| throwbadubadu wrote:
| "However, there was uncertainty about the possibility of these to
| resume functioning after facing extremely low temperatures of the
| lunar night which can go as low as -200 degrees Celsius.
|
| Moreover, its battery needed to remain at a certain level to be
| able to recharge again with the solar dawn."
|
| Naive guy would think that alone can and would be extensively
| tested on earth?
| brushinator wrote:
| And yet the lunar lander and the astronauts on the moon did
| just fine. Did the lunar lander and the body suits have
| heaters?
| kjkjadksj wrote:
| They did, but they also left before the lunar night.
| evgen wrote:
| The humans inside the suits and lander also provided some
| useful heat. For most spacecraft, once you put humans into
| them the problem changes from conserving heat to getting
| rid of it.
| brushinator wrote:
| Ok so at 120 degrees C got it
| NamTaf wrote:
| Kinda crazy what effect different albedos have, isn't it?
| :)
| seabass-labrax wrote:
| If you haven't already, I would highly recommend watching
| 'Apollo 13'[1]. On a technical basis it is really accurate to
| the real-life events. The astronauts having to shut down the
| lunar lander's (LEM) heating system comes into the story
| about half way through. It's one of my all-time favourite
| films!
|
| [1]: https://www.imdb.com/title/tt0112384/
| to11mtm wrote:
| Or, if you want to be a purist, there's this. [0](thank you
| whoever submitted this to HN a while back!)
|
| [0] - https://apolloinrealtime.org/13/
| seabass-labrax wrote:
| Wow, that's amazing. I'm know what I'm going to be doing
| on Sunday!
| toast0 wrote:
| > Naive guy would think that alone can and would be extensively
| tested on earth?
|
| The article says the probe achieved its objectives in the first
| active period. This attempted wakeup was for bonus time.
| NortySpock wrote:
| And it would have been designed to achieve all those
| objectives in the 14-day lunar sunshine period.
|
| You could design a car that runs for a billion miles, but no-
| one could afford it. You pick a reasonable lifespan for a
| project and target your specifications around that.
| pixl97 wrote:
| Ya, and the Indian mission was already one of the lowest
| budget successful missions there has been. The US is one of
| the few countries that can spend billions on missions where
| the lander may last months/years longer than expected.
| warkdarrior wrote:
| [flagged]
| moralestapia wrote:
| This is a troll post, right?
| flashgordon wrote:
| We probably found it cheaper to build it, send it, test it than
| build a lab to get to -200degc :)
| Halfwhit wrote:
| I too like to live dangerously and test in production
| waffletower wrote:
| [flagged]
| HexDecOctBin wrote:
| Hopefully, the Canadian moon rover doesn't shelter and sponsor
| terrorist-gangster nexuses for short term political gains.
|
| Oh wait, there is no Canadian moon rover!
| waffletower wrote:
| We are laughing, but not at your misplaced competitive jibe,
| but at you for stooping even lower by saying it.
| HexDecOctBin wrote:
| What makes you think that the gangsters who extort and
| terrorise Indo-Canadians today will not start doing the
| same to white Canadians tomorrow? You have no idea what
| kind of monster your politicians have raised in your
| backyard; and seeing you domestic politics now, it might
| already be too late to control it.
|
| But feel free to keep laughing, it's good for the health.
| RugnirViking wrote:
| I worked with a few sikh guys at one of my old jobs.
| Lovely chaps.
|
| I'd like for you to meditate long and hard about exactly
| why them wanting their own homeland is so unacceptable to
| an india where indian nationalists (not a majority) did
| bombings and assasainations when seeking independance
| from the raj.
|
| such things were unacceptable then and are unacceptable
| now. But like back then, it would be wrong to punish the
| rest of the population because of actions of so few, or
| to reject outright the idea of independance
| waffletower wrote:
| https://www.economist.com/leaders/2023/09/20/if-india-ordere...
| waffletower wrote:
| I have some points to spare to see how far you will go to
| suppress alleged criminality of the Indian government. Censor
| away and blight your soul some more.
| m348e912 wrote:
| It's strange to me that the only footage released has been low
| res/low frame rate. It seems like a significant oversight to
| neglect to include cameras that can take, store, and transmit
| high quality video. Anyone have any links to footage I might have
| missed?
| petre wrote:
| At least they've sucessfully got a probe onto the Moon, as
| opposed to Russia who poisoned their lead scientist with
| _mushrooms_ after it failed to do so.
| nphard85 wrote:
| Interesting. Is there a source for this claim?
| publicola1990 wrote:
| There has been other probes that continued to operate over
| multiple lunar cycles, how did they manage?
| dgrin91 wrote:
| Few factors -
|
| 1. Design goals. The program had a budget, and with that budget
| their goal was a 14 day target. Anything extra is icing on the
| cake. They could have used an RTG to ensure long term survival,
| but it would have exploded their budget.
|
| 2. If I remember correctly the probe is in the south pole of
| the moon. Most probes are closer to the equator. The poles get
| colder and I think in some circumstances have more night time
|
| 3. Experience. This is their first successful moon probe. Now
| they understand the parameters better, so maybe next one will
| do better?
| thefurdrake wrote:
| JPL and whoever's behind engineering for the ESA have decades
| of experience on the Indian space program.
|
| I believe the approach is to shut down all nonessentials and
| run a heater to keep the battery above failure level during the
| night. This sounds simple but I'm pretty sure it's an absolute
| nightmare to design autonomous systems for, especially when
| you've only encountered those situations theoretically or in a
| controlled lab environment.
|
| Space is hard. It hates us. It hates life. It hates any form of
| order and will actively attempt to destroy it. Trying to make
| things that survive in space is Difficult. It would have been
| easy to go "Lol india amirite", but the fact is, this is one of
| the hardest things humanity can do.
| vc8f6vVV wrote:
| > It hates any form of order and will actively attempt to
| destroy it.
|
| If you are talking about ever increasing entropy, it applies
| to any environment. But keep in mind that the Moon itself is
| a manifestation of order. If it hadn't been the case we would
| have been observing a cloud of dust and gas where our Solar
| system is.
| justsomehnguy wrote:
| > This sounds simple
|
| Especially for someone who never experienced anything lower
| than -5degC. Most cars wouldn't even start at -20degC if not
| equipped with a more powerful generator and battery from the
| factory. This is measly 20deg difference.
| thefurdrake wrote:
| It got below 0F a couple years ago and my garage door
| wouldn't open.
|
| -200C in a vacuum is an entirely-different engineering
| paradigm as I understand it. Materials just don't behave
| the way we expect at regular temp/pressure.
| suckitsam wrote:
| There was a whole writeup (on here, IIRC) about the
| engineering behind the only (or one of less than a
| handful) types of planes that can transit Antarctica
| during the cold, dark months.
|
| The fuel freezes, the oil freezes, the rubber in the
| tires and gaskets becomes brittle, and basically nothing
| normal works. I recall it being similar-but-different to
| the SR71 modifications, where the parts are loose and
| continuously leaks fluids because the materials all
| change shapes so much in the environment they're designed
| for. And of course it all has to return to the initial
| state for (a safe) landing.
| selectodude wrote:
| The Concorde would get something like a foot longer at
| speed due to the expansion of the fuselage.
| paganel wrote:
| Stupid question, and maybe I should have web searched for
| it, but why did the fuselage expend? Something to do with
| the heat generated by the high speed and hence by the
| high friction?
| vc8f6vVV wrote:
| Most modern cars will happily start at -20degC and many
| will start at -30degC without any special additions (don't
| ask me how I know, you just need to know what you are
| doing). Of course it's not -200degC, but one thing to
| remember is that there is no temperature in the vacuum. The
| temperature of the Lunar surface is not it. An object
| without heating can easily reach lower temperatures there,
| yet it may not be that hard to keep that object warm as
| e.g. somewhere in the Arctic as there is no conductivity,
| only the radiation heat transfer.
| stouset wrote:
| I made the mistake of going splitboarding in the
| backcountry a few years back in -20degC with -40degC
| windchill.
|
| Going up the mountain was surprisingly fine. I even had
| taken off both my jackets and was just wearing thermals as
| the heat I was generating working to go uphill was enough
| to keep me comfortable.
|
| Unfortunately when we reached the top, we _also_ ended up
| directly in the wind with no available cover. Within the
| ten minutes it took to put my jackets back on and
| transition to go downhill, I was nearly hypothermic. I
| couldn't even operate my fingers enough to bring the idiot-
| proof magnetic clasp on my helmet together. The whole group
| was on the verge of panic to get off the top of that ridge.
| If we'd stayed there five more minutes, I'm not confident
| we would have made it back home that day.
|
| I can't fully express how obscenely, unconscionably, and
| incomparably cold that was. I have never felt anything like
| it and I hope never to again.
| dotnet00 wrote:
| By having some source of heat, for example, while the Chinese
| rover from a few years ago was solar powered, it had a
| radioisotope heater which used the heat produced by some
| plutonium-238 to keep the electronics warm enough to survive
| the night.
| seatac76 wrote:
| They use RTGs[1] as the power and heat source, I think CY3 was
| just solar powered and did not have thermal protection you get
| from RTGs for electronics.
|
| [1]https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_
| ...
| shauryamanu wrote:
| They are still working on RTGs.
| https://www.thehindubusinessline.com/economy/isro-barc-
| join-...
|
| Above was paywalled, check this https://www.reddit.com/r/ISRO
| /comments/151j6zw/isro_barc_joi...
| pixl97 wrote:
| By spending massive amounts of money.
| CommanderData wrote:
| [flagged]
| 1024core wrote:
| [flagged]
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