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Japan: Moon lander Slim comes back to life and resumes mission
- soco 3y agoLanding upside down is what they call "the glitch"? How could that be fixed, did it have some way to restore its position? Or only the solar cells were turned upside up? What happened there in the end?
- resolutebat 3y agoThe lander has no way to correct its orientation, and in any case was never designed to survive in the lunar night, which starts in a few days on February 1st.
- nottorp 3y ago> was never designed to survive in the lunar night But does it mean it won't actually 'survive' ? What's survival in this case, getting enough power from the solar panel to boot up and transmit again, when the next day comes?
- yencabulator 3y agoSurvival means not being destroyed by the coldness of the lunar night, something like -130 C to even -250 C, for two weeks. Many spacecraft have a radioactive heat source to heat themselves through the cold stretches. It seems for this one, primarily aimed at developing landing methods, that wasn't thought to be worth it.
- HALtheWise 3y agoThis may be a silly question, but shouldn't the attitude thrusters still be restartable?
- echoangle 3y agoIts the second sentence in the Article. It is still in the original position but the angle of sunlight has shifted so light is now hitting the solar panels of the lander.
- thrdbndndn 3y agoI assume it has actuators to correct the upside down position issue as soon as it has access to solar power? Or it has to stay in this position?
- KineticLensman 3y agoNo actuators. It’s basically a box
- dotancohen 3y agoIt has the exact same actuators to correct upside down position issues as does the Toyota Camry.
- bashauma 3y agoThe probe is expected to operate during lunar daylight, i.e., until 2/1. (Note the main mission of SLIM is a "pinpoint landing" and the observation by the probe is just a bonus.) During the remaining three days, JAXA has announced that they will focus on optical observations of the surrounding environment (specifically, some rocks in the surrounding area). So it is hard to imagine they will do this hard schedule of risky additional operations to restore the attitude.
- firtoz 3y agoYou just send the commands upside down and it works
- nottorp 3y agoUnicode already has a special case for this, right? "Upside down hiragana right yourself". "Mirrored upside down hiragana right yourself". And 31284 related emoji.
- jojojaf 3y agoBasically the same as contacting Australia
- Etheryte 3y agoLittle known fact, but this is why binary was chosen to represent data in the digital age, 1-s and 0-s look more or less the same upside down.
- 3y ago
- adrian_b 3y agoActually it has landed on one lateral side, not upside down. The engine nozzles that are now directed upwards were intended to remain on one lateral side. The lander was supposed to rotate one quarter turn after landing, to bring the engine nozzles from downside to a lateral side. Instead of that, it has rotated a half of turn, bringing the nozzles upside, due to an excessive horizontal speed at contact. The solar panels are now on one lateral side instead of on the upper side. Initially that lateral side was opposite to the Sun. After the Moon has rotated, the Sun has begun to illuminate the panels, though it is likely that the generated power has remained much lower than intended. If they can no longer move it, they will have to save power, because they will be able to recharge the battery only during a small part of the Lunar day.
- jacquesm 3y agoMaybe, just maybe they can use the rovers to push it over.
- yencabulator 3y agoThe two rovers it launched are small, one is a rolling ball the size of a baseball, the other is a hopper a few times bigger. Not much pushing happening with them.
- jacquesm 3y agoAh, too bad.
- cubefox 3y ago> Actually it has landed on one lateral side, not upside down. The description "lateral side" only makes sense if the engines are the "bottom" of the craft. Then it did in fact land upside down. Otherwise the engine side would count as a "lateral side".
- adrian_b 3y agoDuring landing, before contact, the engines were the bottom of the craft. However the side with engines was not intended to be the bottom of the craft after landing. Another side has legs and it was intended to become the bottom side after landing, by a quarter turn rotation from the flight orientation. That went wrong by making an extra quarter turn rotation. I have used "lateral side" as corresponding to the intended orientation after landing, not corresponding to the orientation during flight. The engine side was intended to be a lateral side after landing, but instead of that it has become the upper side. What counts is that the lander has made only a quarter turn of additional rotation compared to the original plan, not an additional half turn, as implied by "landing upside down".
- rkagerer 3y agoHere's how it was supposed to land (bear with the video through the boulder scanning discussion): https://youtu.be/nvXLt3ET9mE?t=1384 https://youtu.be/nvXLt3ET9mE?t=1384 Here's how I gather it actually landed: https://static.euronews.com/articles/stories/08/19/58/62/1200x675_cmsv2_59cd42ea-9765-51a3-91ad-083509c20d60-8195862.jpg https://static.euronews.com/articles/stories/08/19/58/62/120... Scott Manley describes it in more detail (don't miss the hilarity around 4:48): https://youtu.be/7bFiJvbKyPs https://youtu.be/7bFiJvbKyPs
- aaron695 3y ago[dead]
- WilTimSon 3y agoI'm curious about this bit: "In a post on X, formerly Twitter, Jaxa shared a photograph taken by Slim of a nearby rock that it nicknamed a "toy poodle"." What does nicknaming mean here? Is it the lander doing some sort of pattern recognition or how exactly does a machine generate a nickname?
- gliptic 3y agoIt = JAXA.
- WilTimSon 3y agoAh, makes sense. Not sure why I didn't just assume that.
- beAbU 3y agoHard to say without an actual link to the twitter post, but I suspect they followed the Curiosity/Ingenuity playbook here, creating a twitter handle that personifies the robot. Posts are made as if it's the actual probe/bot making the updates, in which case the sentence "... that it nicknamed..." makes sense.
- deleted 3y ago[deleted]
- numpad0 3y agoTheir spectrometer team picked candidate rocks within view of the camera, rock A, B, C... then one of spacecraft manager crew said names might be useful, and few minutes later they were all puppies. Forgot the source, sorry.
- skywhopper 3y ago"It" here refers to Jaxa, not the lander.
- kybernetikos 3y agohttps://interestingengineering.com/science/japans-moon-lander-first-images https://interestingengineering.com/science/japans-moon-lande... The team assigned nicknames, I think we're talking about Jaxa rather than Slim.
- beAbU 3y agoShould have collaborated with some of the BattleBots/Robot Wars teams to include one of those flippers that up turn an upside-down bot right-side-up again.
- jacquesm 3y agoPayload...
- deleted 3y ago[deleted]
- jpgvm 3y agoSelf righting combat bots are awesome!
- drtgh 3y agoThey designed the LEVs like that[1][2] for to deploy them some meters before landing. My guess is they expected it may happen with the main probe and something made them not include it in the design (Perhaps to concentrate all on the testing and analysis of the navigation and therefore it would be extra payload as other user comment, or something else, I do not know). [1] LEV-2, https://www.youtube.com/watch?v=S_8TwJgKfYQ https://www.youtube.com/watch?v=S_8TwJgKfYQ [2] LEV-1, https://www.youtube.com/watch?v=Ej4ZMp4a2xw&t=4782s https://www.youtube.com/watch?v=Ej4ZMp4a2xw&t=4782s
- shagie 3y agoPathfinder too - http://tes.asu.edu/PATHFINDER/what_is_p_f.html http://tes.asu.edu/PATHFINDER/what_is_p_f.html > Pathfinder will land during the Martian night. Just before the spacecraft impacts the surface, giant airbags will inflate to cushion the landing. After the spacecraft comes to rest on the surface, the airbags will deflate and three solar panels will unfold. These panels are arranged in a way that will allow the spacecraft to be flipped over if it should land upsidedown. The solar panels will begin providing power to the spacecraft as soon as the sun comes up that first morning on Mars. Though, that's a different configuration for a different planet with a different budget... and a "it can bounce for a while" rather than the pinpoint accuracy that Slim was demonstrating.
- pvaldes 3y agoIt's been a really, really, long journey, a quick nap and like new again.
- nanna 3y ago> Statistically, it has proven very hard to land on the Moon. Only about half of all attempts have succeeded. Why is this still the case given that NASA were able to land humans on the moon 55 years ago, not to mention do so in a way that could also bring them home?
- enlyth 3y agoI'm guessing having humans on board makes it easier, since they can tend to the landing instead of having to do it semi-autonomously all the way from Earth
- tempestn 3y agoThat does make the most sense. Given the technological gap over more than 50 years, that's the one advantage those missions had, and with 6 successful landings (and none of the failures being in the moon landing phase) it couldn't just be luck.
- dotnet00 3y agoTo an extent, given how crewed spaceflight safety standards have improved since then, it was a combination of luck and only doing it 6 times that no crew was lost on the Moon. Famously there were two versions of the president's speech prepared, one for the case that the astronauts would be unable to return.
- tempestn 3y agoYes, agreed that there was some luck involved, certainly. I'm just saying that there were enough successes that it's statistically significant that their results were better than more recent ones. And agreeing with the parent that the manned component is the best explanation for that.
- EliRivers 3y agoAs I recall, Armstrong chose the landing site personally, using the awesome power of looking out of the window and judging a good descent speed for touchdown. He avoided big rocks and craters.
- bookofjoe 3y ago"First Man" (2018) https://youtu.be/PSoRx87OO6k?si=OPCRv2nLyhdvh9Lo https://youtu.be/PSoRx87OO6k?si=OPCRv2nLyhdvh9Lo https://youtu.be/w4GtJB5WAlQ?si=ASRrv1K0akxJwj-I https://youtu.be/w4GtJB5WAlQ?si=ASRrv1K0akxJwj-I Armstrong's coolness under pressure as the Eagle lander's fuel dwindled to within 30 seconds of "Empty" is depicted with gripping intensity in this film.
- Gravityloss 3y agoHe survived a lot of close calls. He ejected in Korea, Gemini 8 spinning, the LLRV crash. And then the moon mission. He was exceptional under pressure. David Scott was flying with him on Gemini and gave kudos in his autobiography.
- witx 3y agoYes! People usually only know him for the moon landing, but those who know a bit more are well aware of this (and and many others) man's courage and life before that. He went through so many life-ending events and still persevered. Gemini 8 alone is very very scary to think about
- kerbs 3y agoIf you’ve played Kerbal, you feel for this.
- RetroTechie 3y ago"The spacecraft ran on battery power for several hours before authorities decided to turn it off to allow for a possible recovery of electricity when the angle of sunlight changed. (..) The lander will analyse the composition of rocks in its search for clues about the origin of the moon, Jaxa said." Not so quick.. does this involve correcting its orientation? Or should this be read as "remains toppled over, but some camera work possible" ? Available solar power must be a big constraint in remainder of this mission, probably?
- szundi 3y agoNot getting up but wait for the sun to get just above the horizon sometime and then turn on
- sp332 3y agoThe solar panels were pointing away from the sun at the time. But the moon is rotating, and the solar panels are now pointing the right way to get power.
- pyinstallwoes 3y agoThe moon is rotating?
- Galaxeblaffer 3y agotechnically yes, 1 rotation takes the roughly the same time as 1 revolution around the earth which as you were probably hinting at is tidally locked
- adolph 3y agoRelated is the infamous 1982 SAT question: The radius of circle B is three times the radius of circle A. Starting from the position shown in the figure, circle A rolls around circle B. When circle A returns to its starting point, how many rotations will it have completed? https://www.scientificamerican.com/article/the-sat-problem-that-everybody-got-wrong/ https://www.scientificamerican.com/article/the-sat-problem-t...
- HarHarVeryFunny 3y agoSounds like Monty Python and the Holy Grail. "I'm not dead yet!" "It's just a flesh wound!"
- szundi 3y agoIt is just like Kerbal
- deleted 3y ago[deleted]
- kuschkufan 3y agoThe armchairism in this thread is something else. Happy the mission is not lost and kudos to JAXA.
- smashed 3y agoTo be honest I had read the entire article and did not get the very important fact that it landed upside down. Perhaps people are reacting to the very bad reporting by the BBC, not at the slim mission team itself.
- _xerces_ 3y agoIt didn't land upside down, it landed upside vertical - 90 degrees off, not 180.
- deleted 3y ago[deleted]
- angiosperm 3y agoIt landed upside-down relative to how it descended. it was supposed to roll over 90 degrees, but turned 180 instead.
- stcredzero 3y agoThe armchairism in this thread is something else. Right. Now we need more comments starting with, "What about...?"
- aa6ll 3y agoDoes someone has an idea for how the communication/fixing was done? Was it radio waves of flipping bits? Or how does that work?
- nothis 3y ago>Its solar cells are working again after a shift in lighting conditions allowed it to catch sunlight, the agency said. >It could not generate power when it landed on 20 January as the solar cells pointed away from the Sun. Sounds like they were just lucky with the angle of sunlight.
- makeitdouble 3y agoYes. I don't remember the details but they also adjusted the power management to basically make it sleep until the right conditions happen, once they could confirm the angle of the panels.
- m3kw9 3y agoI thought it landed upside down. If so they will just try to do stuff like that?
- t43562 3y agoScott Manly did a great explanation. The lander lost a rocket nozzle when it was in the final part of its descent - hovering and taking pictures of the landing site. Nozzles make the rocket's thrust much more effective so basically it lost thrust on one side. It had very good software which adjusted to this and brought it down softly enough to land but it couldn't stop the pitch over. The spacecraft landed within 50m of it's target which is exceptionally good accuracy and that part of it's mission was a complete success. The rocket nozzle problem may have been due to a stuck valve or some other problem and obviously they have work to do on that but apparently something similar has happened on a similar design before.
- NotSammyHagar 3y agoThanks for that. I hadn't heard this detail in the mass media sites I read about it. HackerNews as usual has a succinct summary, why can't normal media be this clear? I think it's because most journalists are missing an engineering background. Just adding those few sentences tells us so much more.
- Suzuran 3y agoWhen I was interviewed on a technical subject by a local affiliate, I was told they are under specific directive to be as non-technical as possible, even if the result becomes technically incorrect. As a result, my answers were trimmed down to be essentially "be scared of scary things". The news is a product being sold to a demographic and the messaging must appease the demographic or they are out of their jobs.
- NotSammyHagar 3y agoIt's not surprising that they don't want to make it confusing and useless for their viewers as anyone sees all the time, but it's possible to describe it in a way that most people can understand, like the person I replied to.
- npteljes 3y ago>I was told they are under specific directive to be as non-technical as possible, even if the result becomes technically incorrect. There could be a sinister undertone to this, but this is how communication works. Common context is a must for successful communication, and news is communication. And, yeah, news needs to be sold in a hard competition, so they do whatever to grab the attention.