[HN Gopher] China releases videos of its Zhurong Mars rover
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China releases videos of its Zhurong Mars rover
 
Author : pseudolus
Score  : 194 points
Date   : 2021-06-28 10:39 UTC (12 hours ago)
 
web link (www.bbc.com)
w3m dump (www.bbc.com)
 
| freddealmeida wrote:
| Let me correct this. China releases CGI of a Mars rover. No way
| they got there. God propaganda is insane
 
  | pavel_lishin wrote:
  | [citation needed]
 
  | sct202 wrote:
  | NASA has been releasing pictures over time of the landing site
  | taken from the Mar Reconnaissance Orbiter and the rover is
  | visible and moving slowly from the lander.
  | https://www.space.com/china-mars-rover-zhurong-nasa-hirise-p...
 
| williesleg wrote:
| Obviously built by a bunch of black and transgender queer china
| engineers.
 
| eunos wrote:
| Physical engineering aside, the operating system used is also
| quite interesting https://cntechpost.com/2021/06/22/chinas-
| tianwen-1-probe-pow...
| 
| real-time response accurate to 8 milliseconds range. I am not
| that familiar with embedded software, but does that value really
| difficult to achieve?
 
  | grawprog wrote:
  | Siemens Siamatics PLC controllers can achieve real time
  | response in the 250ms range.
 
  | magicsmoke wrote:
  | Looks like Kylin OS uses the Linux kernel. While not impossible
  | to use in a real-time application (SpaceX Falcon 9 uses it)
  | there's definitely work involved in stripping it down enough to
  | work as an RTOS. NASA Perseverance uses VxWorks instead, which
  | was designed from the beginning as an RTOS. VxWorks is also
  | proprietary and looks like it's US export restricted.
  | 
  | 8 ms isn't hard to hit. 8 ms with 100% reliability is.
 
    | edrxty wrote:
    | What?
    | 
    | 8ms is incredibly slow for realtime systems. A difficult
    | target for a control system would be three orders of
    | magnitude lower than that on a full size OS like linux.
    | 
    | VxWorks is being partly phased out too, last I heard wind
    | river was pushing people towards their own linux based
    | offering. Speaking from experience it's absolutely miserable
    | to develop on because of the licensing model and reliance on
    | the Eclipse IDE. If you need a low level system
    | FreeRTOS/CMSIS is a far better option and if you want linux
    | compatibility (frequently just the convenience of ssh and
    | rsync) just use real time linux.
 
  | carlsborg wrote:
  | In some "hard real time" systems failure to meet the deadline
  | is treated as system failure. Vs "soft real time" where its a
  | transient error. So the goal is bounded response
  | time/latency/jitter at the 100th percentile.
 
  | smoldesu wrote:
  | It's only impressive in the sense that they have to use really
  | shitty computers to achieve that number. Playing around with
  | Rust on a reasonably powerful x86 box, you'll have no problem
  | writing programs with a response time in _microseconds_ , but
  | they aren't using the same computers you and I do (or Rust for
  | that matter). Word on the street is that most space tech is
  | based on PowerPC, since you can buy decently powerful
  | radiation-hardened RISC chips without breaking the bank (only
  | $300,000 or so).
 
    | edrxty wrote:
    | This commenter is correct. Things like radiation tolerance
    | and power draw are much bigger concerns. I've seen a number
    | of projects using RT systems entirely because they were based
    | on earlier systems that were RT and therefore the engineers
    | just used the same kernel despite having no RT requirements.
    | 
    | PowerPC is popular because there are a couple companies out
    | there that are taking these parts and running them through
    | radiation beams to certify them for spaceflight (essentially
    | profiling their failure modes so devs can account for them).
    | ARM isn't popular yet as they tend to make it difficult to
    | license designs for lower volume silicon but RISC-V in
    | particular is gaining traction here very rapidly.
 
  | justicezyx wrote:
  | https://en.wikipedia.org/wiki/Kylin_(operating_system)
  | 
  | If my impression is correct, this is based on Linux kernel.
  | 
  | Since other comments appearing not mentioning that, just add
  | here in case someone mistaken it with a custom embedded OS.
  | (Although I know little about embedded OS either).
 
  | crazypython wrote:
  | Most games have real-time response around the 8-16 millisecond
  | range.
 
    | edrxty wrote:
    | Games are real time in the sense that their response window
    | is 1/[desired frame rate] of-a-second. As far as hard
    | realtime systems go, they're some of the slowest.
 
      | sitzkrieg wrote:
      | would you say that about games that are designed to run at
      | 125+ fps?
 
  | danhor wrote:
  | Seriously depends on what you do. Iq you're doing really low-
  | level stuff, you could probably get in the microsecond range
  | quite easily (for trivial stuff). But 8 milliseconds doesn't
  | sound that impressive to me.
 
  | edrxty wrote:
  | IIRC you can get into the tens of microseconds with an x86 box
  | running a heavy linux graphic desktop with real time patches.
  | Single digits with core pinning on a light headless system.
  | 
  | Bear in mind that real time performance and throughput are
  | perpetually at odds with each other. Long story short,
  | scheduling things such that everything happens in a tight time
  | window means you need to leave gaps in the timeline.
  | 
  | This tradeoff is variable so you can loosen requirements for
  | running something like a rover where there isn't really all
  | that much need for tight realtime control, it's not trying to
  | achieve micron positioning as it drives around. That means you
  | can use a more efficient CPU and lower your idle current which
  | is probably the real constraint here.
 
| [deleted]
 
| monster_group wrote:
| Those are some awesome videos from Mars. Why is there no coverage
| of this in US media?
 
  | SiempreViernes wrote:
  | One big factor behind the difference of coverage the fact the
  | Chinese are really restrictive with releasing footage: maybe
  | you noticed in the article that the landing happened May 14 but
  | the footage showed up just now.
  | 
  | So it's much less interesting for eg CNN to plan a big feature
  | for the touch down if they can only count of stock footage.
 
    | baybal2 wrote:
    | > maybe you noticed in the article that the landing happened
    | May 14 but the footage showed up just now.
    | 
    | Communist party centennial is on July 1.
    | 
    | The propaganda ministry have a reserve of "highly patriotic
    | news," which they throw on around big events.
 
    | godelski wrote:
    | Also note that when the rover _did_ touchdown there was news
    | about it. Same when it was launched. But the slow release of
    | footage and updates makes it harder to tell compelling
    | stories. Stories happen when things are released, such as
    | now.
 
    | varispeed wrote:
    | Plenty of time to create a video like this without actually
    | landing on Mars.
 
      | ineedasername wrote:
      | And pretty easy for US monitoring of launches to determine
      | if no launch corresponded to this and tell the world it was
      | fake. If was a fake, it would require a fair number of
      | people outside the PRC to remain silent.
 
      | gpt5 wrote:
      | The landing was confirmed with US satellite footage of the
      | landing site: https://www.bbc.com/news/science-
      | environment-57427797
 
      | mahkeiro wrote:
      | This is nonsense, If you want to fake it you can also do it
      | before...
 
        | [deleted]
 
    | JKCalhoun wrote:
    | Good point. Never mind that at this point it's "yesterday's
    | news" (and then some!).
 
  | pp19dd wrote:
  | To be fair, there's definitely plenty of coverage of both
  | rovers. These and all science stories are particularly easy to
  | cover [read: labor-cheap] since everything is spoon-fed on the
  | account of not being able to get boots on the ground.
  | 
  | But what we can't do generate interest. There's only so much
  | shoveling you can do before people not only lose interest, but
  | get repulsed by the attempt.
 
  | fartcannon wrote:
  | Well, since they're competitors in this space, and it's not
  | exactly a novel experience to drive a rover on Mars, they'd
  | probably end up only using it to stir the pot. I guess be
  | thankful they're not doing that?
 
  | reaperducer wrote:
  | _Why is there no coverage of this in US media_
  | 
  | Because you didn't bother to look for it, and just assumed it
  | wasn't there because of your worldview?
  | 
  | I see it in plenty of U.S. media coverage. A quick search turns
  | up CNN as the first result.
 
    | mullen wrote:
    | China's current rover is what the US put on Mars, twice, 16
    | years ago (Those rovers ran for 6 and 12 years).
    | 
    | The US is currently putting nuclear powered rovers on Mars.
    | That is why there is no huge US media coverage of this story
    | in the US.
 
      | bogwog wrote:
      | That's bullshit. China landing a rover on Mars is a huge
      | accomplishment even if it isn't as advanced as what NASA
      | has.
      | 
      | Do you think the editors of CNN/Fox/whatever saw this story
      | and decided not to run with it just because the rover's
      | power system is outdated?
 
        | aardvarkr wrote:
        | They reported it because it's noteworthy but do you
        | really think it's a huge accomplishment for the US and
        | deserves propaganda-level hype on all major news networks
        | for an event that happened on may 16?
        | 
        | Instead you get incredibly hostile and defensive. It's a
        | great accomplishment for the Chinese but seriously man
        | check your biased worldview at the door.
        | 
        | Do you get just as upset when China doesn't report on the
        | US gymnastics superiority in the olympics and instead
        | chooses to focus coverage on the Chinese prowess in
        | weightligting, table tennis, and diving?
 
  | unity1001 wrote:
  | Envy, ill will, sore loser-ness, exceptionalism. Ending up
  | lying, propaganda and obscuring the truth.
 
    | cscurmudgeon wrote:
    | Was there similar coverage of US missions in Chinese press?
    | How do you quantify that?
    | 
    | The US landed a Mars rover almost a quarter of a century ago
    | and there was almost no major coverage of the recent rover
    | mission in the US press.
    | 
    | > sore loser-ness
    | 
    | What does that even mean?
 
      | shadofx wrote:
      | It means that the US had a responsibility to prevent anyone
      | else from landing on Mars, and has failed in that. Should
      | have used NORAD to intercept the Chinese rocket while it
      | goes up, I suppose? That's what you get for sleeping on the
      | job.
 
        | cscurmudgeon wrote:
        | Very poor attempt at humor.
 
        | canadianfella wrote:
        | No.
 
    | woeirua wrote:
    | LOL. I get that bashing the US is popular on this site, but
    | this comment is really detached from reality. The US landed
    | its own rover on Mars not that long ago, and they're not even
    | covering it in the domestic press. Why would anyone expect
    | them to cover another country's rover if they wont cover
    | their own?
 
      | monocasa wrote:
      | Perseverance had (and still has) tons of domestic press.
 
  | coldtea wrote:
  | For the same reason US coverage of Olympic Games are 24/7
  | spotlight on American athletes.
  | 
  | Shauvinism, exceptionalism, and provincialism.
 
    | fma wrote:
    | If you're NBC and you're out to make money from
    | advertisement...would you get more views showing spotlights
    | of athletes from random countries...or spotlight of athletes
    | from the US?
    | 
    | I guarantee you China isn't doing a spotlight on US athletes.
    | Hell, there are some athletes they are taking away the
    | spotlight.
    | 
    | https://radiichina.com/li-ying-coming-out/
 
      | coldtea wrote:
      | > _If you 're NBC and you're out to make money from
      | advertisement...would you get more views showing spotlights
      | of athletes from random countries...or spotlight of
      | athletes from the US?_
      | 
      | If it had a mature audience, and not provincial chauvinists
      | that only know/care for their "heroes" in a sports event,
      | then they'd make money "showing spotlights of athletes from
      | random countries" too, like it happens all over the globe.
      | 
      | > _I guarantee you China isn 't doing a spotlight on US
      | athletes_
      | 
      | Don't know about China, but I've seen the Olympic games TV
      | coverage from several countries, and only the US cancels
      | out the rest of the world. Others get the full picture.
      | 
      | If China does the same, that's their loss, not some new
      | standard the US is OK to follow...
 
  | axguscbklp wrote:
  | I am surprised that there is even as much coverage as there is.
  | We are still getting basically the same footage of big deserts
  | full of broken rock from Mars that we were in the 1970s, it is
  | just in higher resolution now. There is not much reason for a
  | person to get particularly excited about yet another Mars rover
  | unless that person is interested in some pretty technical
  | stuff. And with a Chinese rover, US audiences do not even get a
  | nationalist thrill from news about it. Basically, unless you
  | are into science, the reality of Mars is kind of boring. It is
  | like Antarctica - there can be a lot of drama in getting there
  | and surviving there and traveling around its rough conditions,
  | but actual footage from there is almost entirely just very
  | similar-looking vast white plains.
 
  | ilamont wrote:
  | In Google News, there are articles and video from CNN, ABC,
  | Space.com, and other U.S. news organizations, some of them
  | dating from yesterday (Sunday).
 
  | bilbo0s wrote:
  | Because propaganda.
  | 
  | How much coverage of US missions made it into Chinese media
  | outlets? Significantly less than the coverage of US missions in
  | US media outlets. Why is that? Chinese propaganda.
  | 
  | For the same reasons, the coverage of Chinese missions will be
  | downplayed in US media.
  | 
  | You can't downplay US missions and then ask why the US
  | downplays yours. You already know why. Because of the
  | propaganda war.
 
| llboston wrote:
| I might be too cynical, but I feel dropping a remote camera to
| take this video and releasing it now are mostly a present for
| CCP's 100th birthday, to show how great CCP is.
 
  | justicezyx wrote:
  | Wow, I am not sure are you trying to belittle the engineers and
  | scientists achievement, or deliberately make sure people
  | emphasize CCP's role in this event?
  | 
  | I don't get it, if you don't pay attention to CCP, it's very
  | appropriate to focus on the contribution of the people
  | involved.
  | 
  | The CCP propaganda also emphasize the sacrifice and ingenuity
  | of the engineers and scientists.
  | 
  | Somehow a rando guy online insists to call out CCP. Are you
  | sure people actually likes CCP because of this? I mean, they
  | hate CCP because of CCP's wrong doings, not because CCP is not
  | interested in space exploration, right?
 
  | monocasa wrote:
  | So? Viking I entered Mars orbit in July 1976 for the
  | bicentennial. Of course a country spending literally billions
  | is going to time it well with local goals if it makes sense.
  | 
  | IMO, if anything you get bonus points for achieving goals like
  | this on a a timetable you set, being an additional constraint.
 
| Vaslo wrote:
| The head reminds me of Johnny 5 from Short Circuit for anyone
| that remembers back that far.
 
  | tluyben2 wrote:
  | Immediately what I thought of when I saw it flexing it's
  | wheels!
 
    | koheripbal wrote:
    | Same here. "Number 5 is A L I V E" echoes now on Mars
 
  | pseudolus wrote:
  | Who could forget Fisher Steven's "brownface" portrayal of an
  | Indian scientist?
 
    | pengaru wrote:
    | I am standing here beside myself
 
    | nickpinkston wrote:
    | Whoa - I never knew that!
 
      | northwest65 wrote:
      | The Indians were not impressed, banned him from the country
      | IIRC.
 
| throwaway4good wrote:
| Can anyone explain the sound in the clip? So Mars atmosphere is
| different, making sound travel different? But the weird echo and
| metallic muffle, what explains that - why would the machine be
| particular noisy?
 
  | Vinnl wrote:
  | A Dutch article about this [1] said:
  | 
  | > According to the Chinese space agency CNSA, the sounds are
  | caused by the interaction of different metal parts.
  | 
  | In the video, they also quote the person leading the Mars
  | programme:
  | 
  | > The sound is made by wheels rotating on the surface of the
  | Mars rover. Basically, the sound of different metal objects
  | bumping into each other.
  | 
  | [1] https://nos.nl/artikel/2386872-chinese-marsrover-stuurt-
  | nieu...
 
    | pixelpoet wrote:
    | Hmmm, I've heard plenty of metal things bumping into each
    | other, this sounds more like 0.1 bits/s sloshy MPEG audio.
    | 
    | What I'd like to know is, is this actually how it sounded
    | there, or are we mostly hearing compression artifacts?
 
      | JKCalhoun wrote:
      | Yeah, I thought it sounded like flanging.
 
      | tacticalmook wrote:
      | It should indeed sound distant and muffled with the
      | composition and temperature of Mar's atmosphere. Saw a neat
      | pseudo-documentary on this not too long ago:
      | https://youtu.be/OeYnV9zp7Dk?t=551
 
        | exporectomy wrote:
        | Kind of ridiculous to demonstrate what things sound like
        | while playing eerie random background music over it.
 
      | throwaway4good wrote:
      | Why would it be compression artifacts when they are also
      | sending hires video signal?
      | 
      | This page has some simulations:
      | 
      | https://mars.nasa.gov/mars2020/participate/sounds/
 
    | seaorg wrote:
    | Would you say Dutch news is more objective than American
    | news?
 
      | Vinnl wrote:
      | No, it's just the news I happen to follow because I am
      | Dutch, and it contained the info they were asking after.
 
| imglorp wrote:
| I'm curious about the use of a wireless camera to photograph the
| lander and the rover. It seems like extra weight and complexity
| for purely PR reasons.
| 
| Yes, you need to inspect each vehicle, but the rover can clearly
| examine the lander and move around it, while the lander needs
| only one camera, possibly an existing descent one, to inspect the
| rover.
| 
| Is Earth in an ideology war again?
 
  | luma wrote:
  | Possibly a technology test? I don't think it's any more or less
  | silly than a helicopter that also doesn't actually do any
  | science other than testing out the concept for future missions.
 
    | aardvarkr wrote:
    | That's pretty close to the definition of science... form a
    | hypothesis and test it then report your results. Not every
    | test has to be microbiological or geological in origin to be
    | considered "science". They're also getting to test the
    | resiliency of consumer grade computers and electronics in the
    | Martian atmosphere and probably many many other experimental
    | ideas that aren't public knowledge.
 
    | alpha_squared wrote:
    | > ...a helicopter that also doesn't actually do any science
    | other than testing out the concept for future missions.
    | 
    | Isn't that scientific? Testing out the hypothesis of aerial
    | maneuverability in Martian airpsace?
 
  | aga98mtl wrote:
  | Space exploration is a prestige game among world powers since
  | the very beginning. China needs good PR pictures to show they
  | can do just as well as NASA. If we are lucky they will try to
  | one up each other for decades to come.
 
  | [deleted]
 
  | 3pt14159 wrote:
  | It's useful for future historians. We're not just exploring
  | space, we're leaving something behind for the future of
  | humanity.
 
  | CMay wrote:
  | Something could go wrong with any of those and cameras can be
  | pretty light these days since we put them in doorbells, so I
  | doubt they're sweating it when there are multiple potential
  | benefits to having it there. :)
  | 
  | Curiosity weighed almost 2000 lbs, so it's not like rovers on
  | Mars are afraid to weigh anything which is not to say they
  | don't run the numbers.
 
  | marcodiego wrote:
  | These missions usually have scientific AND engineering
  | objectives. Having a spare camera that the hover put anywhere
  | may not be very valuable scientifically, but it validates the
  | engineering of all communication, power and mechanical systems
  | involved. That will allow more advanced scientific objectives
  | in the future.
 
  | DiogenesKynikos wrote:
  | It may be scientifically worthless, but the public pays for
  | these missions and the public likes pretty pictures. JunoCam on
  | NASA's Jupiter orbiter, Juno, was added in order to give the
  | public pretty pictures of Jupiter.[1] I personally think that's
  | really cool.
  | 
  | 1. https://en.wikipedia.org/wiki/JunoCam
 
  | iso1631 wrote:
  | > It seems like extra weight and complexity for purely PR
  | reasons.
  | 
  | And that's the thing that gets a public supportive of your
  | space program and thus the resources keep flowing.
  | 
  | Drop the PR and you drop the funding.
 
    | erdos4d wrote:
    | This is a democratic model you are assuming, I don't think
    | CCP needs the Chinese people to "support" anything they do,
    | it really just boils down to whether the CCP leaders support
    | it.
 
      | melling wrote:
      | National pride is very important in either model.
 
        | sidlls wrote:
        | Yes, but the people with the pride differ. In the
        | genocidal dictatorship of China only the pride of the CCP
        | matters very much. It can be coerced or ignored in other
        | groups.
 
        | shigawire wrote:
        | I don't agree. They still need to assert their
        | legitimately through successful governance and projects.
 
      | dang wrote:
      | Please don't take HN threads on generic ideological
      | tangents. Those lead to highly repetitive discussion, which
      | is tedious and usually turns nasty -- therefore not what we
      | want here.
      | 
      | https://news.ycombinator.com/newsguidelines.html
      | 
      | https://hn.algolia.com/?dateRange=all&page=0&prefix=true&so
      | r...
      | 
      | https://hn.algolia.com/?dateRange=all&page=0&prefix=true&so
      | r...
 
      | dr-detroit wrote:
      | I dont know any average people who support the western
      | system of oppressive wealth consolidation.
 
| oldgun wrote:
| Great technological advancement. I believe congratulations is in
| order.
 
| semiconduction wrote:
| Will we see Star Wars like battles in our lifetimes? That would
| be dope.
 
  | rasz wrote:
  | Ad Astra has a cool Moon shootout scene.
  | https://www.youtube.com/watch?v=EH9NvOVil-k
  | 
  | how it was made https://www.youtube.com/watch?v=2_qWvfxdzRg
 
    | nextaccountic wrote:
    | It's unfortunate that those moon cars resembled rovers from
    | the 70s (like
    | https://en.wikipedia.org/wiki/Lunar_Roving_Vehicle), and not
    | something more plausible.
 
      | hulitu wrote:
      | Yeah. Like a Tesla with a crash test dummy at its steering
      | wheel.
 
    | squarefoot wrote:
    | That movie turned out an huge disappointment for me; that
    | moon chase could have been the base to develop an interesting
    | subplot (if not a much better main plot), but no, it was just
    | a self contained albeit technically well made, action scene
    | that could give nothing to a terrible movie.
 
      | dekhn wrote:
      | agreed, it was on of the better parts of world-building in
      | the movie.
 
| plank_time wrote:
| How did China know how to make their rover without sending a
| bunch of probes onto Mars? Did NASA share its data and info with
| China so that they knew what specs to make the solar panels, etc?
 
  | sinxccc wrote:
  | That's why the rover landing happened 3 months after the probe
  | reached Mars orbit. They spent that time to do all the
  | reconnaissance work to prepare the landing.
  | 
  | Also this is the reason this mission is considered to be a
  | great success, it shows their ability to landing on a totally
  | unknown planet.
 
  | EMM_386 wrote:
  | > How did China know how to make their rover without sending a
  | bunch of probes onto Mars?
  | 
  | Why would they need probes? The Mars atmospheric composition
  | isn't exactly classified information, they know it's a solid
  | surface. The rest is just math and some very complex
  | engineering.
 
  | russli1993 wrote:
  | CNSA did acknowledge that they benefited from prior
  | explorations to mars done by everyone, including NASA, soviet
  | union, ESA and more. They are able to find general scientific
  | data on mars, such as atmospheric density, composition,
  | potential weather events, general topography in the public
  | domain (I mean, wikiepdia has a lot of these information). For
  | these, they should and are appreciating scientists going before
  | them are sharing these information in the public domain. But I
  | am sure NASA and everyone else did not release all super
  | detailed data, such as detailed topology maps. And from public
  | available info, they also know about general designs of NASA's
  | landers and rovers, and the troubles NASA has faced operating
  | these crafts on mars. If they learn from NASA's experiences,
  | they can avoid a huge amount of unknowns and negative
  | encounters. These are significant assistance when you are
  | engineering systems. The pioneer is always way more difficult.
  | So of course respect is paid and hats off to NASA and other
  | pioneers.
  | 
  | But knowing these are not enough for you to build and operate a
  | fully successful mission. Even if you had the entire CAD file
  | of a NASA lander and rover, you don't know why they are
  | designed that way, you will not operate, use and troubleshoot
  | issues correctly. You need to build the system from ground up,
  | so the people on your teams have full understanding of every
  | single "why" and "how". Only then will you have full control
  | and ensure the mission is success.
  | 
  | I am sure you had experience taking ownership to a software
  | project written by others. You always have go to the original
  | designer to ask "why" and "how". The knowledge transfer often
  | last months and countless meetings. If you don't fully
  | understand, you can't fix issues or build new features. Most
  | people would rather build their own then to fix something they
  | don't fully understand.
  | 
  | For CNSA, they can access public available data. Then they have
  | to simulate, wind tunnel tests, how to land, what shape of
  | lander they need, how to balance and control the lander etc.
  | They need to build up their understanding of the entire system.
  | They actually has been improving their technology and
  | understanding of atmospheric and controlled powered landing
  | from earth and moon missions. One of things they did
  | differently is adding a flap to the lander to stabilize it in
  | flight, they said it was to increase the lander's robustness
  | when encountering more extreme weather.
  | 
  | For solar panels, knowing the distance to the sun, the
  | atmospheric density, pressure, composition, force of gravity on
  | mars, you can estimate the theoretical max of the solar energy
  | available per unit of area. Then you could say assume only 30%
  | is available due to weather. I am sure they have more advanced
  | ways to estimate. Interesting fact about the rover, it has a
  | solar heat capture and retention system. And they use the heat
  | for thermo-control at night instead of electricity captured
  | from solar panels, saving electricity use.
  | 
  | For where to land, topology and maps of mars is in public
  | domain. You can find a general region where to land but these
  | data are not detailed enough to actually land. And mars surface
  | could have changed since these were captured. So tianwen-1
  | contains a orbiter and the lander. The orbiter has instruments
  | such has high resolution imaging. They arrived mars orbit in
  | February, and the 3 months since the orbiter was collecting
  | data on mars. From these data they finalized their landing
  | plans.
  | 
  | This is China's first spacecraft to ever travel this far. They
  | also don't have communication network between mars and earth.
  | So Tianwen-1's orbiter is also a communication satellite.
  | 
  | The impressive thing is the engineering side, how they
  | engineered the system that each component all worked correctly
  | in one go. The rocket: the rocket required to launch tianwen-1
  | (weighs 5 tons) to mars orbit was only tested successfully in
  | dec 2019. China also doesn't have earth mars communication
  | satellites and fully operational deep space communication
  | system before this mission. This the first time all these
  | system are tested live. To fly a spacecraft to mars for the
  | first time, have it being captured by mars, and orbit mars
  | correctly. Take data on mars. Release the lander. The lander
  | going through atmosphere, releasing parachute at super sonic
  | speeds, the lander detaches from parachute and uses a rocket
  | engine to fly. At height of 100m, optical imaging and laser
  | maps out the ground and autonomously navigate the craft to soft
  | land on flat ground. Orbiter forms communication link between
  | mars rover and earth. Mars rover collects sun light, drives,
  | survives the elements of mars (so far).
  | 
  | Overall, they are standing on the shoulders of people who went
  | before them. One shouldn't look down on their success, nor
  | should they over-hype their success.
  | 
  | CNSA said Zhurong landed 3km away from their designed
  | coordinate. For the first 42 mars days, zhurong traveled 236m.
 
    | distribot wrote:
    | Why would NASA not release detailed topology maps? Doesn't
    | that have a lot of value to al researchers around the world?
 
  | spaetzleesser wrote:
  | Isn't NASA pretty open with their designs? I don't think it's
  | hard to find their specs if you do some digging.
 
    | abecedarius wrote:
    | Yeah. This sounds like a good place to start:
    | https://www.amazon.com/Design-Engineering-Curiosity-
    | Performs...
 
  | Clewza313 wrote:
  | China has been sending probes to the Moon since 2007:
  | 
  | https://en.wikipedia.org/wiki/Chinese_Lunar_Exploration_Prog...
  | 
  | Once you've got that down pat, it's not _that_ different to
  | land one on Mars, especially since the Chinese rover was small
  | enough not to require the elaborate skyhook approach.
  | 
  | Also, NASA is legally prohibited from cooperating with China on
  | anything space-related.
 
    | myrandomcomment wrote:
    | It's completely different. Let's start with the moon has no
    | atmosphere so you do not use parachutes to land on the moon
    | like you do on Mars.
    | 
    | Your statement is nonsense.
 
      | Clewza313 wrote:
      | Of course it's _different_ , but you're still sending a
      | probe to a celestial body, so things like building the
      | rocket, designing radiation-hardened hardware, space
      | communications, launching on a desired trajectory,
      | automated landing with retro-propulsion etc are all similar
      | and needed for both. Basically, if you're going to practice
      | the Moon is the place to do it, and that's why the US,
      | Soviet, Chinese and now Indian space programs are all
      | following the same basic game plan.
 
    | plank_time wrote:
    | Of course it's different. You need to know how to make solar
    | panels so that it will work on Mars. It's different than
    | those you would need for the moon. It would have to work
    | through the dust storms.
    | 
    | The equipment would need to be rated differently. How the
    | signal is sent from the rover to the orbiter would be
    | different, etc. There's a lot of knowledge that you would
    | need to build up about Mars and having probes on Mars and the
    | logistics of sending data to and from Earth via orbiter that
    | you would need before jumping all the way to sending a large
    | expensive rover to Mars.
    | 
    | That's interesting about NASA not being allowed to share
    | data. I really wonder how China was able to leap to sending a
    | rover without lots of investment in understanding everything
    | else about it.
 
      | Teever wrote:
      | > You need to know how to make solar panels so that it will
      | work on Mars. It's different than those you would need for
      | the moon.
      | 
      | Can you elaborate on this?
 
      | unity1001 wrote:
      | > I really wonder how China was able to leap to sending a
      | rover without lots of investment in understanding
      | everything else about it.
      | 
      | Continent-wide public education churning out legions after
      | legions of STEM graduates?
 
        | sidlls wrote:
        | The proportion of Chinese stem graduates who aren't
        | simply copying their way around and are gifted enough to
        | run these programs is likely about the same as the
        | proportion anywhere else. Chinese people are no more or
        | less intelligent than anyone else.
 
        | wiz21c wrote:
        | In my country, and I guess otherd in western Europe, we
        | often fail to appreciate the sheer power of those "other"
        | countries such as Russia or China. Many are still stuck
        | in the colonialist vision of things where Europe and US
        | were vastly superior. This is not true anymore. And as
        | you point out, intelligence is uniformly distributed.
 
        | failuser wrote:
        | Days when Russia could send problems to Mars are long
        | over, so with regards to Russia reality ironically
        | corrected itself to match the US expectations.
 
        | ptr2voidStar wrote:
        | Shocking that you have to state this fact. Is this HN or
        | YouTube?
        | 
        | SMDH
 
        | blackoil wrote:
        | Not supporting OPs assertion, but. Even with same
        | proportion they will have huge advantage in absolute nos.
        | Also society and government are lot different, changing
        | the way and proportion of people persevere for a
        | particular career option.
 
        | jjcc wrote:
        | let's put ideology aside. It's quite interesting to watch
        | different societies, governance, cultures evolving,
        | cooperating,competing among each other. Eastern world is
        | more likely have low entropy societies while Western have
        | high entropy societies.
        | 
        | Both have strength and weakness. Low entropy societies
        | are more efficient, extremely good at building physical
        | things. But tend to have less varieties. High societies
        | are more chaotic, but also more innovative, more
        | productive in spiritual domain. Not only in technologies
        | but also arts ,etc.
        | 
        | It would be ideal that both societies can cooperate and
        | share the benefits leveraging advantages of both worlds.
        | But in reality it's quite complex and not going to a good
        | direction in short term
 
        | cscurmudgeon wrote:
        | The best of which promptly move to US and Europe.
 
        | onethought wrote:
        | I think you severely underestimate the quantity of top
        | scoring STEM graduates.
        | 
        | What you really mean is "the richest/privileged move to
        | US and Europe"
 
      | icegreentea2 wrote:
      | Many of the design outputs of the NASA rover programs are
      | public domain. For example, the peak solar panel rating of
      | the MER (Opportunity and Spirit) is published, the size of
      | the panels are known (or can easily by estimated), the
      | power needed to drive the rovers around is published, the
      | weight of the rover is published, the size of wheels can be
      | easily estimated (or is published).
      | 
      | The logistics of sending data back can be reasonably
      | considered to be a challenge that could be solved on the
      | first try. The first space probe that NASA managed to
      | actually get to Mars (Mariner) worked. The first landers
      | that NASA managed to get to Mars (Viking) worked.
 
      | throwaway4good wrote:
      | Don't make the mistake thinking that this happened without
      | "lots of investment". The Chinese space program is massive
      | and has been running for decades.
 
| sprafa wrote:
| people are sleeping on China. Sure they copy everything now, but
| so did US, japan and everybody in the beggining.
 
  | vlovich123 wrote:
  | Who is people? There's been lots of people noting this parallel
  | for a very long time. In fact, it's exactly China's playbook.
  | 
  | Here's an example from 2007 where NDT is discussing China's
  | emergence that people were missing at the time:
  | https://www.haydenplanetarium.org/tyson/commentary/2007-08-0...
  | 
  | There was another talk (from NDT too IIRC) I recall seeing that
  | compared the amount of academic papers China puts out. It's a
  | poor metric & there is more low-quality submissions coming out
  | of China, but overall they were set to overtake the US. Expect
  | university prestige to start migrating east to top Chinese
  | universities (assuming they become more friendly for
  | immigration).
 
  | nabla9 wrote:
  | Samuel Slater ("Father of the American Industrial Revolution")
  | is known in the UK as "Slater the Traitor". He stole the
  | textile machinery designs from UK as an apprentice, then
  | migrated to the US and build his own mills. British law banned
  | exporting textile mill designs.
 
  | president wrote:
  | Copying is one thing. State-sponsored wholesale transfer of
  | trade theft is another. Now, I don't doubt for one second that
  | the US/CIA has not done anything shady like that in the past
  | but I do not believe it has ever been on the scale of effort
  | that China has undertaken. And I say to my own country's
  | detriment - more power to them. While the US fumbles with
  | domestic politics, social justice endeavors, and enriching
  | other countries, China has risen to take its place by taking
  | the opposite stance and focusing all its energy on making
  | itself the foremost global economic giant.
 
  | CountDrewku wrote:
  | What people? Plenty of people are concerned with what they're
  | doing. US government is too inept to do anything or they're
  | willingly cooperating with them.
 
  | aeternum wrote:
  | What can the US do?
  | 
  | China's population is a huge advantage right now, China has
  | figured out how to create a mostly participatory economy so
  | they have 10x the number of brains engaged vs. the US.
  | 
  | Each US citizen must be 10x more productive just to tie. If the
  | US gov were smart, we would make it significantly easier for
  | those with skills to immigrate, but unfortunately we seem to be
  | set on doing the opposite.
  | 
  | On top of that, China is making smart educational choices like
  | making basic comp-sci required. The US educational system is
  | using decades old curriculum or just cancelling classes
  | altogether.
 
    | bogwog wrote:
    | But considering how the Chinese government brutally oppresses
    | its own people, those advantages aren't worth much.
    | 
    | When/if the CCP is overthrown and a democratically elected
    | government takes its place, then maybe China will become the
    | new world leader.
 
      | aeternum wrote:
      | That's a narrative that most democratic countries want to
      | be true, but that does not necessarily make it true.
      | 
      | A strict autocratic government is quicker at making
      | decisions and may actually be ideal assuming it optimizes
      | for the long-term best interest of the country and does not
      | become corrupt. Only time will tell if the CCP is able to
      | do this.
 
    | distribot wrote:
    | Demographic collapse, irresponsible extractive industry, and
    | in fact many citizens are excluded from the most dynamic
    | parts of the country by the Hukou system.
    | 
    | China is a really interesting place that has had an
    | incredible meteoric rise, but there are problems.
 
| jrue wrote:
| Oh no! The U.S. really needs to step up its game if it wants to
| stay competitive. (Honestly I couldn't care less, but if a new
| space race injects further investment into science/space, I'm
| happy to be an instigator.)
 
| eunos wrote:
| I can't imagine what would happen if some unidentified
| apparitions appeared on the videos.
 
| someperson wrote:
| Users interesting in this story may also be interested in this
| great 55 minute documentary covering the first few years of
| NASA's Curiosity rover:
| https://www.youtube.com/watch?v=qaUhLXolGaI (the active rover
| before NASA's more recent Perseverance landing).
 
| yellow_lead wrote:
| On a non-serious note, it would be entertaining to see the two
| rovers fight on Mars.
 
  | mattkevan wrote:
  | Robot Wars, but on Mars. I'd watch that.
 
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