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China's Jade Rabbit lunar rover dies on moon
- lutusp 13y agoThis is a shame, but most people -- even in space programs -- don't appreciate how cold the Moon's shaded areas become. It's now estimated that these areas get to 26 Kelvins -- that's 26 degrees above absolute zero. To get a sense of how cold this is, Pluto's average surface temperature is seven degrees warmer. Also consider that, because of the specifics of the Moon's orbit, a given area stays shaded for just over 14 days each month. That's a long time at a very low temperature. Unless a spacecraft has a way to heat itself during the long lunar night, its electronics will self-destruct.
- Scaevolus 13y agoDoes China have the capabilities and reserves of radioactive material to make probes with RTGs?
- TrainedMonkey 13y agoLooks like it: http://en.wikipedia.org/wiki/Timeline_of_the_Republic_of_China%27s_nuclear_program http://en.wikipedia.org/wiki/Timeline_of_the_Republic_of_Chi... They had capability to produce required material decades ago. They also have sufficient nuclear arsenal to warrant maintaining stockpiles of the stuff: http://en.wikipedia.org/wiki/China_and_weapons_of_mass_destruction#Nuclear_weapons http://en.wikipedia.org/wiki/China_and_weapons_of_mass_destr...
- seszett 13y agoYou are confusing the Republic of China, commonly called Taiwan (which is the subject of your first link) with the People's Republic of China, which sent this robot to the moon. Both of them have nuclear power though (but only PRC has nuclear weapons) and radioactive material in sufficient quantities.
- sp332 13y agoIt has a radioisotope heating unit https://en.wikipedia.org/wiki/Yutu_%28rover%29#Specifications https://en.wikipedia.org/wiki/Yutu_%28rover%29#Specification...
- lutusp 13y agoOnline accounts say there's a radiation source for heating during the lunar night, but it seems one of the solar panels used for normal operations didn't fold up properly (by folding up these panels are closer to the heat source) before the sun went down, and that exposed component froze and was ruined, which sealed the spacecraft's fate. Source: http://www.dvice.com/2014-2-12/chinas-jade-rabbit-lunar-rover-freezes-death-moon http://www.dvice.com/2014-2-12/chinas-jade-rabbit-lunar-rove...
- sgrove 13y ago> Pluto's average surface temperature is seven degrees warmer. What about the temperature in Pluto's shaded regions (if there are any)?
- exhilaration 13y agoMaybe Pluto's atmosphere keeps the temperature warmer? I assume it's too far from the sun to have any unshaded versus shaded regions.
- sp332 13y agoThe average "temperature" of empty space is 3K, due to heating by background radiation. That's a big enough difference to have a warmer sun-facing side and a cold, shaded side.
- Pxtl 13y agoThat said, temperature works differently in hard vacuum - with no air to conduct/convect the heat away, isolated objects don't actually get "cold" the way they would in a pool of liquid nitrogen or something. Notice you don't hear about the ISS freezing at night.
- unspecified 13y agoThe ISS is only in shade for 45 minutes at a time, which is orders of magnitude less than a lunar night. But speaking of that: how long is too long to spend at 26K in a vacuum? Are there any good articles/videos that talk about what happens to various materials at such extreme temperatures in a vacuum?
- mpyne 13y agoI think the point of the parent comment was that simply being in a cold vacuum doesn't make you instantly cold. That still requires a process of heat transfer, which occurs in a fluid via conduction, convection, and radiation. When immersed in a vacuum the conduction and convection heat transfer paths are sharply reduced, so the question then becomes how fast do you cool off via radiation alone? I'm not a physicist so I don't know, but it's certainly nowhere near as fast as conduction/convection (in fact I believe heat dissipation was actually problematic for many spacecraft designs).
- lutusp 13y agoAs it turns out, even on earth's surface, radiation is a more efficient heat transfer method than conduction and convection through the air. Objects under a clear sky quickly drop below air temperature in many circumstances.
- hrkristian 13y agoThank you! I did an hour jog tonight, and most of that time was spent trying to figure out why there was frost on the ground with an air temperature above freezing and a warm breeze.
- oftenwrong 13y ago>To get a sense of how cold this is, Pluto's average surface temperature is seven degrees warmer. That doesn't give me a good sense because I have no idea how Pluto's average surface temperature compares to typical on-Earth temperatures that I have experienced. This gives me a better sense: 26 K = -247.2 C
- shitgoose 13y agoIs that with the windchill?
- deleted 13y ago[deleted]
- officemonkey 13y agoNo atmosphere, therefore no wind, thus no windchill.
- akfanta 13y agoYou must be fun at parties.
- comex 13y agoOr -413 F for us silly Americans.
- fallinghawks 13y agoOh, so something like Canadian winter. ;)
- lutusp 13y agoIMHO you're better off thinking in Kelvins. Room temperature is 295 Kelvins, the cosmic background radiation (the leftover glow of the Big Bang) is 2.7 Kelvins, and between the stars, far from any particular star, an object naturally cools to the universe's background temperature of 2.7 Kelvins.
- Buttons840 13y agoFun bit of trivia: If a moon rover could maintain speed of about 11 miles per hour (17 Kilometers per hour) forever, it could circle the moon in 28 days, and would be moving fast enough to stay on the light side of the moon. That doesn't seem very fast, but with the moons low gravity and all.... You'd have to be doing science while catching big air.
- 1morewebdev 13y agoSuppose China were to send another Rover up in the next 5 years, and it found this one. In theory, could this one be repaired? Or will the "electronics self-destruct" be thorough by then?
- sounds 13y agoSome assumptions I have to make are: • The RTG in Yutu (the rover already up) will last that long • Yutu does not move, get struck by a meteor, or other normal events in space that will damage it further • The team who understands Yutu is still around in 5 years Then China could, in theory: • Assemble a rover with the repair parts on board • Launch it to the moon • Land on the moon intact • Locate Yutu • Do a remotely-operated repair There's a lot of risk in each of those steps. It might be an interesting mission to push the boundaries of tele-operated robotics etc. Realistically it seems less expensive to launch a second rover that has been improved based on the lessons learned from Yutu. Hopefully China can think of lots of things to improve the second time. Interesting thought experiment, though.
- 3327 13y agoShame as well space exploration is still so primitive and infant that I root for any nation venturing out there. Too bad its clouted by military achievements.
- demallien 13y agoWell that sucks. Is anyone here a big follower of the Chinese space programme? I follow "western" space efforts pretty closely, but with heavy military involvement, a preoccupation with face-saving, and the language barrier, I find the Chinese programme nigh on impossible to track. Do they have the same sort of spending split that NASA has with respect to the manned v. unmanned programmes? Or does their unmanned programme get substantially more than a pittance? As things stand, I'm not even able to tell if they are actually serious about space outside of military use, or if it's all just a prestige play. Anyone care to fill in some detail?
- dengnan 13y agoWe, Chinese, do not know too much details either. It is hard for us to know details about the spending. I tried to google it with key words like "Chang'e budget", but found nothing useful. However, I did found an article about the history[0]. Here is some fact: Back to 90s, there were Chinese scientists suggesting for lunar exploration. But the projects requires a budget around 1.5B, which was declined by the prime minister LI Peng (Family name first.) 0. http://www.baike.com/wiki/%E4%B8%AD%E5%9B%BD%E6%8E%A2%E6%9C%88%E8%AE%A1%E5%88%92 http://www.baike.com/wiki/%E4%B8%AD%E5%9B%BD%E6%8E%A2%E6%9C%...
- SEJeff 13y agoI wish the Chinese space program the best. Every success pushes mankind (all nationalities) forward in our understanding of the universe.
- TrainedMonkey 13y agoThat. Hopefully we can get another space race this time against China. Sending people to Mars or establishing moon colony for example.
- SEJeff 13y agoI suspect Elon Musk will win that one and as a result America :) SpaceX is doing quite well thusfar.
- TrainedMonkey 13y agoChinese space program had come a long way. Interesting test would be how they handle this failure. Will they go assigning blame and scapegoats. Or will they learn from this mistake and improve quality control/redundancy for future missions.
- icegreentea 13y agoIts entirely possible to do both...
- 1morewebdev 13y agoI expect the latter, they aren't known to give up big dreams so easily. Consider for instance that India and Russia have had numerous failed launches for various rockets and / or space probes and both countries continue to try again and eventually succeed. Why would China not try again? I pray they do. Chinese or American or Russian or Indian, I want to see a minimal human habitat on the moon in my lifetime. Our species deserves that much, for all the work done so far.
- grogenaut 13y agoThere is no such thing as deserve, especially in cases like this. There is no ice cream for failure. Well I mean you can go out and buy ice cream if you're at mission control and not dead. And I guess you can eat some astronaut ice cream as your air runs out or you freeze to death if you are in space. But this isn't some deserve type thing.
- pgrote 13y agoYou try, you fail, you learn. It's fantastic more countries are venturing into space exploration. Their next effort will build upon what they've learned. Do countries typically share what they learn about these failures?
- tomswartz07 13y agoI know NASA has been publishing reports on all of their missions for a number of years. Here's a small collection: http://www.hq.nasa.gov/alsj/alsj-mrs.html http://www.hq.nasa.gov/alsj/alsj-mrs.html I believe that after Challenger, NASA has even published technical reports regarding all aspects of the cause of failure and the steps to prevent it.
- njharman 13y agoMy biggest shock was "Why haven't I heard about this lunar rover before!?" I'm not news hound, but I do spend too much time on tech sites (HN/Reddit) that would report this. I remember years ago mention of China (and India) moon missions. But, really first man mad object to land in 37 years should have been blasted over most news sources. After shock... "Kick ass, we're (finally) getting back on the moon!"
- AceJohnny2 13y agoIt was definitely on the front page of all techie sites, including HN and Reddit. Many comments thereof lamented the lack of coverage by the mainstream media.
- bane 13y agoIt even made the Daily Show with Patrick Stewart hilariously dressed up as the rover, slowly dying. http://www.thedailyshow.com/watch/tue-february-4-2014/who-froze-jade-rabbit- http://www.thedailyshow.com/watch/tue-february-4-2014/who-fr...
- cygwin98 13y agoNot surprised. He has been bashing China for a while, which is the trending topic in the mainstream media anyway. Though I do wish some of the media agencies strike out of the group-thinking, and examine what NASA has been up to for the past decade, and what needs to be improved in terms of space exploration.
- trekky1700 13y agoI haven't seen any trend of bashing China, unless of course reporting honestly is bashing. NASA, despite its huge budget cuts, in the last decade has operated three rovers on Mars, landed one new one (via spectacular jet crane awesomeness). They've built new types of rockets, taken pictures of the universe, continued to do valuable research in science and space. Continued to be a major contributor to the ISS. And much much more. I think the real question here is, where have you been for the last decade?
- cygwin98 13y agoThe team is still working on it. There is hope still. http://gbtimes.com/opinion/jade-rabbit-still-fighting-despite-death-reports http://gbtimes.com/opinion/jade-rabbit-still-fighting-despit...
- kryptiskt 13y agoSeems like there is hope: http://www.planetary.org/blogs/emily-lakdawalla/2014/possible-hope-for-yutu.html http://www.planetary.org/blogs/emily-lakdawalla/2014/possibl...
- deleted 13y ago[deleted]
- reuven 13y agoI found it quite appropriate that the referenced CBC article referred to it as a moon "buggy." More seriously, I'm excited to see more countries, and more people in general, involved in space exploration. I also think that instead of pointing to the rover's failure, we shout point to its success: Launching a rover to the moon and getting it to work in any way, shape, or form, is a pretty amazing triumph. Sure, the US did it several decades ago, but not all NASA missions were successful, and it's to be expected that you need a few iterations to get the bugs out.
- jonknee 13y agoTo be fair that's also what the US called the Lunar Rover: http://en.wikipedia.org/wiki/Lunar_Roving_Vehicle http://en.wikipedia.org/wiki/Lunar_Roving_Vehicle
- devindotcom 13y agoLet's not bury Yutu alive in our haste to eulogize it. The rover is awake and transmitting. Lot of news sites have been reporting on news from many many hours ago. My guess is the mechanical error interfered with the solar intake and delayed the power-on process. http://news.xinhuanet.com/english/sci/2014-02/13/c_133111283.htm http://news.xinhuanet.com/english/sci/2014-02/13/c_133111283...
- smtf 13y agoDoes anyone know if there are images from this rover available on-line ? I'd love to see some hi rez shots of the Earth with the Moon's horizon in the shot.
- frank_harmonic 13y agoHere are some images of a mock-up of the rover, being shown off at a science conference in Beijing. It's an impressive technical achievement. http://www.stuff.co.nz/science/9448077/China-sending-jade-rabbit-rover-to-moon http://www.stuff.co.nz/science/9448077/China-sending-jade-ra... http://www.businessweek.com/articles/2013-11-26/chinas-jade-rabbit-moonshot http://www.businessweek.com/articles/2013-11-26/chinas-jade-... http://imarstore.blogspot.com/2013/11/technology-china-going-to-land-lunar.html http://imarstore.blogspot.com/2013/11/technology-china-going... The question is, why is Europe being nuked in the background? Note how the images are from at least 3 different angles, so it's not like some reporter got a Photoshopped picture ... http://www.reddit.com/r/WTF/comments/1t37gn/wtf_is_a_mushroom_cloud_doing_over_europe_in_the/ http://www.reddit.com/r/WTF/comments/1t37gn/wtf_is_a_mushroo... http://rt.com/news/europe-nuclear-explosion-china-440/ http://rt.com/news/europe-nuclear-explosion-china-440/
- duncan_bayne 13y agoGood luck getting the warranty honoured ;)
- jccooper 13y agoHard to say what happened from the sketchy reports, but there's been some mention of "mechanical problems" due to lunar dust, and hibernation problems. I guess they have some mechanical movement involved in hibernation mode. Pre-positioning solar arrays, maybe? Storing instruments? Lunar dust is notoriously abrasive, having formed in a non-erosive setting. It's a well known problem for lunar exploration, and NASA's done a lot of work on it. Not a lot of recent practical experience, of course. The Chang'e designers must have known about the problem. Apparently they underestimated it, or just missed. Hopefully there's some good lessons learned for future missions. Getting there and working for a lunar day is a pretty good job in itself.
- 10098 13y agoI like the name "Jade Rabbit" :)
- officemonkey 13y agoIt sounds like a dildo name to me.
- lob4tt 13y agoPeople are limited by what they live with.
- chj 13y agoCulture difference. Jade Rabbit is a figure in Chinese legend, companion of a fairy named Chang'e.
- officemonkey 13y ago>companion of a fairy named Chang Now it even sounds more like a dildo name.
- frank_harmonic 13y agoIt is a dildo name, if you believe the Jon Stewart show clip in the other comment on this page ...
- tarzan3419 13y agoNews: it wakes up now.
- devindotcom 13y agoActually, it's working - not perfectly, but it's 'awake,' sending and receiving signals: http://news.xinhuanet.com/english/sci/2014-02/13/c_133111283.htm http://news.xinhuanet.com/english/sci/2014-02/13/c_133111283... Xinhua is adding new info on Twitter: https://twitter.com/XHNews https://twitter.com/XHNews
- dengnan 13y agoFYI, according to recent news[0], The lunar rover is recovered now. Sorry that I did not find a source in English. 0. http://www.bbc.co.uk/zhongwen/simp/china/2014/02/140213_yutu_awake.shtml http://www.bbc.co.uk/zhongwen/simp/china/2014/02/140213_yutu...