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NASA Space Science

Voyager 1 Fires Up Thrusters After 37 Years (nasa.gov) 127

If you tried to start a car that's been sitting in a garage for decades, you might not expect the engine to respond. But a set of thrusters aboard the Voyager 1 spacecraft successfully fired up Wednesday after 37 years without use. NASA announces: Voyager 1, NASA's farthest and fastest spacecraft, is the only human-made object in interstellar space, the environment between the stars. The spacecraft, which has been flying for 40 years, relies on small devices called thrusters to orient itself so it can communicate with Earth. These thrusters fire in tiny pulses, or "puffs," lasting mere milliseconds, to subtly rotate the spacecraft so that its antenna points at our planet. Now, the Voyager team is able to use a set of four backup thrusters, dormant since 1980. "With these thrusters that are still functional after 37 years without use, we will be able to extend the life of the Voyager 1 spacecraft by two to three years," said Suzanne Dodd, project manager for Voyager at NASA's Jet Propulsion Laboratory, Pasadena, California.
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Voyager 1 Fires Up Thrusters After 37 Years

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  • by SuperKendall ( 25149 ) on Friday December 01, 2017 @06:56PM (#55661473)

    That honestly boggles the mind to think of something built so long ago, sitting in the harsh environment of space still able to function that well - not to mention all of the other hardware working well enough to instruct the thrusters to fire. Well done.

    • by Bruce Perens ( 3872 ) <bruce@perens.com> on Friday December 01, 2017 @07:00PM (#55661493) Homepage Journal
      It's not even in our solar system any longer, having traversed the heliosphere of the solar wind into true interstellar space. Power from the nuclear thermal generator runs out in about 2020.
      • Sorry, the really is obligatory:
        https://xkcd.com/1189/ [xkcd.com]
        And this from 2014:
        https://motherboard.vice.com/en_us/article/ezvpvj/voyager-maybe-didnt-leave-the-solar-system-yet-again-again-again [vice.com]
        But I like Munroe's take better.
        And I get the feeling that they may pronounce the thing dead a few times too...
        We may someday get a Pythonesque "I'm not dead yet" from this interesting little device we tossed into the sky...
        • Re: (Score:3, Funny)

          by aix tom ( 902140 )

          I only believe it has left "our backyard" when we get a ticket for flying a vehicle without a license in public interstellar space.

        • The part that worries me isn't just that they can't seem to figure out where the edge of the solar system is, it is that the conditions there do not match predictions, and yet nobody thought, "maybe we should scale back our predictions about things more than 10 AUs away" or something.

          If we can't predict Earth's radiation belts, and we can't predict the conditions at the edges of the solar system, why do we think we can accurately see 14 billion years away?

          • The part that worries me isn't just that they can't seem to figure out where the edge of the solar system is, it is that the conditions there do not match predictions, and yet nobody thought, "maybe we should scale back our predictions about things more than 10 AUs away" or something.

            If we can't predict Earth's radiation belts, and we can't predict the conditions at the edges of the solar system, why do we think we can accurately see 14 billion years away?

            OK, if you want to go down that road we could damage a bunch of theoretical disciplines...
            I'm alright with that in principal but it's gonna break my heart the first time I see a nicely dressed PhD holding a sign saying
            Will extrapolate sparse data for food!

            • Right, if the best defense of science is a jobs program, maybe we should silo that part of the data, and let the science part just be smaller?

              • No, it's OK to keep smacking our heads against a wall till we figure things out, wall builders gotta eat too.
                Maybe be a little less pontificating about the theory du jour...
                and in that vein, I wonder whose house Elon's car will land on...

                This is Air Force Space Command, we are tracking a red sports car falling through the upper stratosphere...
                Do we get to shoot at that sucker or what?
      • Can we redefine the solar system so it can leave it one last time?

    • by 93 Escort Wagon ( 326346 ) on Friday December 01, 2017 @07:05PM (#55661519)

      Yeah, I agree it's amazing... but I'm not looking forward to when it eventually returns.

    • by guruevi ( 827432 ) <evi AT evcircuits DOT com> on Friday December 01, 2017 @07:13PM (#55661569) Homepage

      What's harsh about space other than it being relatively cold? Besides some solar radiation (which it's probably too far for anyway) there is nothing to interact with the systems, no molecules or fluctuations of radiation or physical pressure/stress that interact with it so it won't corrode or fatigue.

      Yes, it's amazing that it still works because the design was good. What's more amazing is that they didn't fuck up the data transmission to interact with the hardware/software on the system. You're talking about 50's and 60's era electronics and hand-made/hand-programmed stuff that's still working at rates like 40 bits per seconds with nibble-sized serial communications to the CPU, how many programmers still know how much a nibble is these days and how to craft a message using it on modern systems?

      • by nmb3000 ( 741169 ) <nmb3000@that-google-mail-site.com> on Friday December 01, 2017 @07:46PM (#55661725) Journal

        What's harsh about space other than it being relatively cold?

        What comes to mind:

        A temperature of minus 455 degrees Fahrenheit (only about 5 degrees above absolute zero). Many materials and electrical components do not behave or age the same when subjected to decades of extreme temperatures and it wouldn't be a surprise at all to find some materials slowly getting brittle or changing shape or thermal or electrical conduction.

        Radiation. A complete lack of protection from a planet's magnetic field or atmosphere means every single gamma ray heading the right direction hits it, hence the shielding and hardened components used to build the satellites. Maybe this drops off as it moves away from the sun, but we really don't know what the nature of space beyond the sun's immediate influence looks like.

        Heat dissipation. No atmosphere means there is no convection so all heat must be dissipated via radiation emissions, which can be very slow. This means if you have hot spots in your electronics or the RTG power system without proper heat sinks, it can build up to a thermal failure.

        And in space, no one can hear you scream.

        • Because space is mostly vacuum heat-exchange does not happen the way that it does in a atom-filled environment such as earth. A unheated object will get colder and colder slowly because of black-body radiation but as it does the radiation emitted becomes less and less which means that it takes a very long time to cool down and even the small amount of heat generated by the plutonium radioactive decay is enough to keep the craft well above CMB temperature
        • by gumbi west ( 610122 ) on Friday December 01, 2017 @10:33PM (#55662265) Journal

          The radiation is mostly cosmic and, if you've ever priced a chip that is hardened for space travel, you'll know it isn't a minor price difference. It's nasty.

        • by Chris Katko ( 2923353 ) on Saturday December 02, 2017 @03:29AM (#55662785)

          >but we really don't know what the nature of space beyond the sun's immediate influence looks like.

          If only we could construct some sort of vehicle that could traverse space and send back signals...

        • What's harsh about space other than it being relatively cold?

          What comes to mind:

          A temperature of minus 455 degrees Fahrenheit (only about 5 degrees above absolute zero). Many materials and electrical components do not behave or age the same when subjected to decades of extreme temperatures and it wouldn't be a surprise at all to find some materials slowly getting brittle or changing shape or thermal or electrical conduction.

          ...

          Heat dissipation. No atmosphere means there is no convection so all heat must be dissipated via radiation emissions, which can be very slow. This means if you have hot spots in your electronics or the RTG power system without proper heat sinks, it can build up to a thermal failure.

          And in space, no one can hear you scream.

          It is pretty cold out there. The mean temperature for matter in interstellar space is 3.2 K, which is the Cosmic Microwave Background of 2.7 K plus 0.5 K because of integrated starlight. But by far the major amount of heating Voyager gets its from its 3 RTGs mounted on a short boom that together still put out 4.5 kw of heat. Currently 249 watts of electrical power are available to run Voyager, a lot of that is used for electrical heaters (the transmitter is just 22.4 watts). I did a bit of Googling trying t

        • Good news! Electricity is radiation!

          Also, electrical current is heat. See also: Ohm's Law, Heat Exchanger. (hint: when considering heat dissipation, you left out conduction to everywhere other than air. You're missing convection in space, so you lose the fan on top of the heat sink, but you don't lose conduction so your heat sinks still all work.)

          And people can hear you scream if you die in an explosion, or at least your suit gasses are released while you're screaming. (Yes, explosions make sound in space;

          • you don't lose conduction so your heat sinks still all work.

            In a vacuum? What do they conduct the heat to?

            • *sigh*

              to the heat sink . The problem isn't that space is hot or that your device will be hot in space. The problem is localized heating on one part of your device.

              Notice that they're listing temperature as a problem because it is so cold? Not because it is so hot? The heating issue is localized heating, eg, a pinpoint of heat right on your IC.

          • Electricity is radiation!

            Electricity is heat.

            You don't seem to understand what "is" means. Electricity is linked to radiation and heat, but electricity is neither radiation nor heat.

            • You're mistaking distinctions that help you understand the physics for the physics itself.

              You can't actually separate the parts of the phenomenon in this case.

              You're just parading ignorance as understanding, and then attempting to correct deeper understanding.

              Without radiation, electrons can't move. You can't separate these laws. Actually, almost everything other than gravity is already unified...

              • That's a pretty high horse you've got here!
                You might have understood those concepts but you do a poor job of communicating it.

                Electricity is heat.

                This sentence is quite simply 100% wrong.

      • Really? Just cold space is, is it? Do you even know what Voyager went through on its way through the solar system? That probe was designed by the best of the best for just a dozen or so years of life expectancy. It has been through huge magnetic fields, radiation, dust, the heliopause and many other things. These designers really knew what they were doing. Oh, and it's still running on its original power source. How cool is that?!

      • by thegarbz ( 1787294 ) on Saturday December 02, 2017 @02:34AM (#55662697)

        What's harsh about space other than it being relatively cold?

        That is much like saying what's harsh about the inside of the sun other than it being relatively hot. Or what's harsh about the surface of venus other than it rains sulphuric acid.

        Electronics lasting 30+ years at only a fraction of a temperature above absolute zero, a point where molecules themselves stop moving completely is amazing. Physical stress isn't the only killer of equipment. The amazing part isn't the programming but those 50s and 60s era electronics still ticking along. I don't have anything from the 50s or 60s anymore that I haven't had to repair. Even back then electronics used chemically reactive components capable of drying out or physically changing, and I'm sure none of it would do so well submerged in liquid nitrogen either.

        That just reminded me something. Liquid nitrogen is very effective at converting heat. Electronics in space typically undergo immense stress as there's no convection possible. They gradually cool to incredibly cold temperatures and then when they fire up have to rely on only radiation to dissipate heat. It's counter intuitive but if your simple design has a heatsink to run here on 25C earth then it will instantly overheat in the -270C space. milliwatts cause stress.

      • The hardest part is that in the movies everybody dies, unless they have transporter beams and gravity generators. And we don't have transporter beams or gravity generators.

        So the hard part is the terrible anxiety of imagining the electrons surviving without a space suit.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      That honestly boggles the mind to think of something built so long ago, sitting in the harsh environment of space still able to function that well - not to mention all of the other hardware working well enough to instruct the thrusters to fire. Well done.

      Back when shit was built in the United States by Americans. Source: family member was project manager for Voyager II.

      • You mean, back when shit was built to last against the expressed wishes of the beancounters-in-charge who only wanted the probe to last long enough for the 4 planetary encounters.

        Detroit showed us that "built in the United States by Americans" is not an indicator of quality.

    • by Brett Buck ( 811747 ) on Friday December 01, 2017 @08:30PM (#55661913)

      For these thrusters (which I think are Aerojet 0.2-lb monoprop, MR-103 series), there's nothing to degrade from mere age or vacuum, and the environmental thermal cycling is negligible. So it is not that surprising that they still work. Using them is another story, and pulsing certainly does degrade them (eventually - hundreds of thousands of pulses).

            It's not terribly unusual to switch to redundant equipment after decades and have it work. Essentially we rely on that working, and I have seen many examples of it working perfectly well. Vacuum is a very good storage medium for anything that does not outgas. Radiation degrades solid-state electronics and power supply components (particularly high-voltage components) are somewhat prone to degrading from age or outgassing. Longest I have personally been involved with is a prime flight computer that was believed to have failed on the day after the launch that was turned on 32 years later as a final test, and that worked fine for at least a few hours. But other components were switched to (of necessity) after ~20 years fired right up and worked fine, showing the same parameters as the day we turned it off.

      • There's nothing to degrade on the thrusters themselves, but the valves that feed them are mechanical items and potentially subject to cold welding and other means of getting stuck. There have been thruster failures in deep-space missions.

      • by rastos1 ( 601318 )

        For these thrusters (which I think are Aerojet 0.2-lb monoprop, MR-103 series),

        I'm curious (and know nothing about the subject). How do the thrusters work? Is there a fuel and a valve that has to open to release the fuel? Is the valve moved electrically? Is there some kind of spark plug that has to ignite the fuel? For thrust lasting a millisecond - isn't it enough just have a compressed gas container and release a bit of the gas without actually igniting it?

        • by Brett Buck ( 811747 ) on Saturday December 02, 2017 @11:56AM (#55664061)

          It's not less than a millisecond, I think the minimum on-time is 15 milliseconds (you can go lower but you get disproportionate amounts of error).

                    It's an electrically-driven valve, a skinny tube with an injector at the end, which is embedded in the catalyst. When the fuel is released, it squirts out the injector and onto the catalyst. This causes it to decompose into steam (think putting hydrogen peroxide on a cut in your skin, but vastly more energetic). The steam is then accelerated out a nozzle, creating thrust.

                  As far as rocket engines go, it's not very efficient, and typically you have to heat the catalyst bed with a heater to keep the thermal shock of a firing from cracking the catalyst into dust. That, and development of "varnish" in the (tiny) injector passages - baked-on crud like a baking pan, is what causes them to wear out. One or both of those is apparently a factor in degradation of the prime attitude control set.

                    It's not terribly good for attitude control purposes due to the limited pulse life in the "fire once, wait 3 days, fire again" duty cycle, but it has the advantage of being very small (0.15 or so lb) and very inexpensive (I think something like $20000 a piece now, much less at the time) and has an extraordinary number of flights on it.

    • Hopefully someone will find a time machine to go back to when humans were technology advanced.
    • by xystren ( 522982 )
      As they say, "They don't make them like they used to." Case and point right there.
  • The space between the stars? Show me somewhere that isn't between two stars.

    It seems NASA has an answer at https://spaceplace.nasa.gov/in... [nasa.gov]

    • Re: (Score:2, Funny)

      by Anonymous Coward

      The space between the stars? Show me somewhere that isn't between two stars.

      Harvey Weinstein's dick. According to my calculations, it was periodically positioned inside a star at one time or another.

    • by hey! ( 33014 )

      In 1668, John Wilkins attempted to construct a language [wikipedia.org] which works the way you want language to work: everything made sense, everything was systematic, down to the way words were formed. Robert Hooke (of Hooke's Law fame) even wrote a scientific paper in it, describing the operation of a pocket watch. It never caught on, because making everything consistent and sensible also makes things unbearably cumbersome.

      People use language to accomplish things, and the construct words to do useful things, not adher

  • Just pull out the choke, pump the throttle, put a cartridge in the Coffman starter and fire it.

  • by Anonymous Coward on Friday December 01, 2017 @07:12PM (#55661567)

    FYI, you can see what each antenna in NASA's Deep Space Network is doing at any given moment by Looking at this site. [nasa.gov].

    Below each antenna is the craft being communicated to. Clicking on the antenna and then "+ more detail" will get you some info about signal strengths, transmission rates, round trip light times, and more.

    I don't see one right this moment but it is common to find one of the 70m antennas talking to one of the Voyagers. Right now Goldstone antenna 14 (70m) is talking with New Horizons.

    Captcha = acquire

    • by Anonymous Coward

      As of the time of my post, Madrid is getting downlink data from voyager 1, and Canberra has a downlink carrier for voyager 2.

  • left the solar system. There is the very real possibility that some Russian Cosmonauts have ended up there.

    LK

  • by kimgkimg ( 957949 ) on Friday December 01, 2017 @07:32PM (#55661671)
    Yeah well that's all well and good until it comes back looking to merge with the creator.
  • Some 6 years ago us kids decided he couldn't drive anymore, and he wouldn't give up his keys. I swapped a couple of his ignition wires, truck wouldn't start and dad (who used to be an A-1 mechanic) (now with the alzheimer's option) couldn't figure out why.

    6 years later dad is still going strong, health wise, is totally gone, mentally wise, and I don't remember which wires I crossed and am not an A-1 mechanic. Plus 4 flat tires, and a truck that hasn't moved in 6 years/

    31 years from now? My niece is
  • by kackle ( 910159 ) on Friday December 01, 2017 @10:09PM (#55662219)
    Fifty fears from now, imagine space aliens come to earth with our satellite, and ask us to play for them what's on the records. We look around, but, embarrassed, can't find a turntable.
    • by Cramer ( 69040 )

      Don't need one. With a high enough resolution flat bed scanner, we have software that can "play" it back from the image. (the same basic technology as today's laser based turntables.)

  • I like this thing is still working at nearly 40 years old and 20 light hours away, when my computer and phone update weekly, and I doubt my hardware would be supported in 30 years even if it still worked.

"The most important thing in a man is not what he knows, but what he is." -- Narciso Yepes

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