back to article Japanese hack gets space probe back on track

It took five years of painstaking work but the Japanese space agency has got its Akatsuki probe back on track. The Japan Aerospace Exploration Agency (JAXA) has confirmed that a careful combination of telematics, testing, and tentative orbital corrections have put the atmospheric probe into orbit around Venus, albeit half-a- …

  1. websey

    Awesome

    Awesome that they could fix it from this distance. These are the things that make me proud to be human :)

    1. Voland's right hand Silver badge

      Re: Awesome

      Not fix - work around using thrusters that were never designed for this mode of operation.

      1. HildyJ Silver badge

        Re: Awesome

        Whether you call it a fix or a workaround, the ability of some people to figure out what they can do with what they are given is amazing.

        How many projects are prematurely and unnecessarily declared failures because the manual, the specs, the documentation, declares that they have failed?

        1. Anonymous Coward
          Anonymous Coward

          Re: Awesome

          Aye but by the same token the real question is: How many projects are hailed as resounding successes because the politicians, vested interests or other gurus declare them to be ?

          1. Anonymous Coward
            Pint

            Re: Awesome

            Because some weasels declare victory where there's none should neither void nor detract from damned hard earned success. These people managed to take an Awww shit and turn in an Atta-boy. Been there, done that too many times, and no, I didn't even get a T-shirt.

            To that team: Damn fine work! I'd buy but I remember how much Kirins, Sapporos, and Asahis cost. Still, enjoy.

            1. annodomini2
              Pint

              Re: Awesome

              @ Jack of Shadows

              I would say more of a 'Bugger!' to 'Be reyht!'

              Still Beer though

        2. allthecoolshortnamesweretaken

          Re: Awesome

          Gene Kranz: I don't care about what anything was DESIGNED to do, I care about what it CAN do.

      2. RyokuMas
        Thumb Up

        Re: Awesome

        Neither was the LEM engine on Apollo 13 - in space, you work with what you've got... credit to the team!

      3. Fred Flintstone Gold badge

        Re: Awesome

        Not fix - work around using thrusters that were never designed for this mode of operation.

        Basically, THIS is what we originally called hacking :).

    2. Sandtitz Silver badge
      Thumb Up

      Re: Awesome

      "The oxidizer was now useless, so the JAXA team dumped it to lighten the spacecraft."

      Very interesting this. Are space probes usually made with components that can be jettisoned, or was that the plan once the probe was orbiting Venus? Are they using explosive bolts?

      1. Martin Budden

        Re: Awesome @Sandtitz

        I had assumed that the "oxidizer" was a fluid which was vented, rather than a component which was detached.

        They may have even gained a small thrust from venting it.

      2. cray74

        Re: Awesome

        "Are space probes usually made with components that can be jettisoned, or was that the plan once the probe was orbiting Venus? "

        Akatsuki used hydrazine (fuel) and nitrogen tetroxide (NTO, the oxidizer) for its 500-Newton main engine, and just hydrazine for its twelve attitude thrusters. NTO has a liquid range of -11C to 22C at 1 bar pressure, and is always stored as a liquid in spacecraft. (Its storage liquid nature is one reason for its popularity, the other being that NTO is hypergolic with hydrazine. )

        Therefore, venting NTO is a matter of opening a valve and allowing the tank pressure to squirt it into space.

        In Akatsuki's case, it was not deliberately planned to dump the oxidizer. Rather, when the main engine broke, nothing else on the spacecraft required the NTO. The little RCS motors didn't need it, the power systems didn't need, it was just dead mass that the little RCS motors would have to push around. So, a valve was opened and the oxidizer spewed into space.

        1. Vic

          Re: Awesome

          NTO is hypergolic with hydrazine.

          Isn't everything?

          Vic.

          1. cray74

            Re: Awesome

            Isn't everything?

            Hydrazine is used in a wide range of industrial chemistry and does horrible things to living tissues, but that's all in non-hypergolic reactions.

            It's usually oxidizers, not fuels, that are broadly reactive. Liquid oxygen, hydrogen peroxide, and the ever-popular chlorine trifluoride react energetically with many substances.

    3. Anonymous Coward
      Anonymous Coward

      Re: Awesome

      It's also a partial answer to all those "we need manned missions to fix things that might go wrong" statements. Trying risky procedures (or very time consuming ones) is so much less stressful when there are no people on board.

  2. Anonymous Coward
    Happy

    Wow!

    Good job.

  3. Ugotta B. Kiddingme
    Pint

    Well done!

    Sapporos and/or Asahis all round

    1. Martin Budden
      Pint

      Re: Well done!

      and/or a Robot Ninja.

  4. John Smith 19 Gold badge
    Thumb Up

    An astonishing demonstration of patience.

    Just staggering.

    1. Richard Taylor 2
      Pint

      Re: An astonishing demonstration of patience.

      I think an extraordinary degree of patience for all of these deep solar system projects is a prerequisite. Along with understanding, low cunning and a great technical competence.

  5. plingwoo

    Mr miyagi say: Thrusters on, thrusters off.

  6. Your alien overlord - fear me

    Of course if they'd built it properly in the first place, none of this would have happened. But that's the negative view :-)

    1. Mark 85 Silver badge

      It's space and rocket engineering. Crap happens to good projects.

    2. Michael H.F. Wilkinson

      Dear alien overlord (not mine, so I fear you not)

      If you have successfully designed a spacecraft and got it to orbit around another planet, you can comment on the design. Except that you would probably not, because you know how hard it is, and how much luck is needed. For all you know, the component failed due to micro-meteorite impact.

      And yes, I did notice the smiley, but I am afraid the joke fell a bit flat, but it is always difficult, attempting humor in an alien language ;-)

    3. defiler

      Shoosht!

      Just needed more struts.

  7. This post has been deleted by a moderator

  8. Timbo Bronze badge

    Just as well....

    ...that none of the lead Japanese admins and techs on this project didn't commit "seppuku" at the time of the initial failure...as they really would have been up a creek without a paddle.

    Good for them that their perseverance paid off. Hope they can get some data from it - they've waited long enough !!

    1. Mark 85 Silver badge

      Re: Just as well....

      Let's also give some kudos the project management for not shutting it down after the engine disaster.

  9. Martin Budden
    Flame

    "This caused the main engine nozzle to crack and break off, a scenario that was replicated on Earth."

    That would have been a pretty hairy moment in the testing room: the nozzle flying off while the engine is active.

    1. Gene Cash Silver badge

      Actually the normal mode of failure for a rocket engine is to explode as hard as possible, which is even hairier.

      1. Stoneshop Silver badge
        Flame

        Ignition!

        Third page: "And this is what it may look like if something goes wrong. The same test cell, or its remains, is shown."

        It's happening less often than in the early days of rocket engineering, but it's not entirely eliminated and I doubt it ever will.

        1. Anonymous Coward
          Anonymous Coward

          Re: Ignition!

          This from the guy whose team never had a day off sick due to an industrial accident,which in many ways is even more awesome than this project.

          If you're working with stuff where evaporating liquid silver is used as a coolant, you're braver than I am.

  10. Doctor Evil

    rocket men

    Apparently there are some steely-eyed missile men working for JAXA. Well done!

  11. Michael H.F. Wilkinson
    Pint

    I will see your Kirin and raise you an Asahi Black!

    Well done those boffins!

  12. 0laf

    Always impressed by the resourcefulness of rocket scientists. Do they design the machines in such a way to make all these options possible?

    Doesn't really matter, brilliant work and I hope they get their science!

  13. Anonymous Coward
    Anonymous Coward

    Always impressed by the resourcefulness of rocket scientists.

    Oh come on, it's not like it is .. oh, wait..

    :)

  14. wolfetone Silver badge

    See what can be done in a country where they censor pornography and Fax machines still reign supreme?

  15. kmac499

    Just goes to prove

    Rocket Science easy; it's all about the F = ma

    Rocket Engineering tricky; Huge congratultions to the team.

    1. Anonymous Coward
      Anonymous Coward

      Re: Just goes to prove Rocket Science easy; it's all about the F = ma

      Really? A relative who has worked on manned spaceflight admitted to me a few years back that he had found his old MSc thesis, and wasn't able to understand it.

      Rocket science has moved on a bit since Isaac Newton. A quick look just at the three body problem will show you some interesting integrals.

  16. Stevie

    Bah!

    Unfortunate coincidence that once again there's Japanese macinery unexpectedly in the sky on December 7th.

    Were UFOs involved?

  17. Paul Woodhouse

    impressed... they didn't even need to get any duct tape up there to fix it either....

    1. Richard Taylor 2

      duct tape only holds the world together

      1. Cynic_999

        It was lack of WD40 that caused the problem in the first place!

  18. iranu

    Artemis Satellite - Non-Geostationary Orbit

    This may be a bit long, but I had a tiny part in it's subsequent success.

    Nearly 20 years ago I worked for a company that was part of a consortium to produce the Artemis satellite. One of the innovations was an ion propulsion engine that used xenon to keep the orbiter at the correct inclination.

    This engine was quite small, not much more than a meter in length and had a series of small diameter tubes around 12mm in diameter, made from small sections of stainless steel (SS) pipe welded together, in order to transport the xenon from the tank to the engine. These pipes were welded using an automated autogenous welding machine.

    The manufacture of the satellite had suffered numerous set backs and it was touch and go as to whether it would be completed due to budget over-runs and delay. The propulsion lab encountered a number of problems associated with the welding quite far into the production of the unit and the materials lab (on site) were asked to investigate.

    Subsequent analysis from supplied welded coupon samples showed that some of the pipes were made from the wrong SS alloy (not connected with the welding problems). In order for SS to be welded and remain corrosion resistant then you have to use an alloy that contains titanium (or niobium), which preferentially forms titanium carbide rather than chromium carbide when welded, because you want the chromium to remain in solution which is what provides the corrosion resistance. If chromium carbide precipitates then the percentage of chromium in solution drops thus reducing the corrosion resistance and potentially lead to cracking. This is known as "weld decay".

    For some reason 316 stainless pipe had been supplied rather 316L (niobium or titanium stabilised). When the project manager for the ion propulsion engine came into the lab and was informed of the error, he went green and had to be sat down with a nice cup of tea! It looked like this screw up would put the kibosh on the whole project. Millions wasted.

    We had to find out the extent of the problem, so a tiny scraping of each pipe section that had already been welded and manufactured was taken (dozens of them) and then examined in the scanning electron microscope (SEM) to identify if the section was 316 OR 316L. It took 2 weeks and the diagnosis was not good. There was a mix-match of the two alloys across every transport tube.

    In the mean time we asked the propulsion lab to produce enough welded sections from the two alloys so we could perform a complete re-qualification process in order to provide all the data for the engineers to say whether the ion propulsion engine was fit to be stored and then fly. The previous qualification process had taken 6 months. We did the new one in 4 weeks!

    Some of us were sleeping at work (I bagged the labs photographic dark room!) and we would order in a takeaway each night followed by "a full english" in the morning from the canteen! (all on expenses of course)

    Subsequently the ion propulsion engine was qualified to fly.

    When the satellite was launched a failure of the launcher meant that the satellite was put into the wrong orbit. The only way to finally get the thing into the right orbit was to use the ion propulsion engine. It worked! The engine was so good that it was operating greater than the designed efficiency so was able to not only 'boost' it to the correct orbit but also provide a good lifespan.

    It was a simple mislabelling of the bar stock at one supplier that led to the whole fracas.

    https://en.wikipedia.org/wiki/Artemis_%28satellite%29

    http://www.aerospace-technology.com/projects/artemis/

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