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Communications The Military United States

Long-Lost US Military Satellite Found By Amateur Radio Operator (npr.org) 79

Tilley, an amateur radio operator living in Canada, found a "zombie" military satellite that was supposed to shut down in 1972. NPR reports: Recently, Tilley got interested in a communications satellite he thought might still be alive -- or at least among the living dead. LES-5, built by the Massachusetts Institute of Technology's Lincoln Laboratory, was launched in 1967. Tilley was inspired by another amateur who in 2016 had found LES-1, an earlier satellite built by the same lab. What was intriguing to him about LES-5 was that if it was still working, it might be the oldest functioning satellite still in geostationary orbit. By scouring the Internet, he found a paper describing the radio frequency that LES-5, an experimental military UHF communications satellite, should be operating on -- if it was still alive. So he decided to have a look.

"This required the building of an antenna, erecting a new structure to support it. Pre-amps, filters, stuff that takes time to gather and put all together," he says. "When you have a family and a busy business, you don't really have a lot of time for that," he says. But then came the COVID-19 pandemic. British Columbia, where Tilley lives, was on lockdown. Like many of us, suddenly Tilley had time on his hands. He used it to look for LES-5, and on March 24, he hit the ham radio equivalent of pay dirt.
While Tilley thinks it may be possible to send commands to the satellite, the MIT lab that built LES-5 didn't comment on the matter when NPR inquired.
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Long-Lost US Military Satellite Found By Amateur Radio Operator

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  • Tilley thinks it may be possible to send commands to the satellite.

    Could it send a laser beam to the White House?

  • LES-5 is just tired and shagged out following a prolonged squawk [wikipedia.org].

  • by Pikoro ( 844299 ) <init.init@sh> on Friday April 24, 2020 @09:45PM (#59987680) Homepage Journal

    The lack of comments on this baffles me. If ever there were "nerd news", this is it. HAM radio used to be the heart and soul of the "geek" culture, but wow, a satellite that is supposed to be dead that may still be awake? Especially from that early era.

    I've always thought that satellites that are about to be retired should have their systems "open sourced" and let others use the satellite for other purposes. Talk about citizen science! There could be a lot of still useful data that could be extracted from these retired systems.

    Hell, limit the opening of the data to just data, and not the control systems. I'm sure that all kinds of useful science could be done if left to the community.

    • Re: (Score:2, Informative)

      by Strider- ( 39683 )

      Most satellites in orbit are just dumb bent pipe repeaters. They don’t do any particular science.

    • by cusco ( 717999 ) <brian@bixby.gmail@com> on Friday April 24, 2020 @11:21PM (#59987952)

      The lack of comments on this baffles me.

      Same here, there was an article this morning about Boston Robotics' Spot being used to carry a tablet to tele-interview patients thought to have COVID-19 and almost all the comments were about how horrible that was.

      let others use the satellite for other purposes.

      Agree completely, I can think of several interesting experiments just off the top of my head. I was always disappointed that they deorbited MIR rather than using about the same amount of fuel to boost it into a parking orbit either as a museum or to use for parts in the future.

    • by eclectro ( 227083 ) on Friday April 24, 2020 @11:47PM (#59988036)

      Talk about citizen science! There could be a lot of still useful data that could be extracted from these retired systems.

      Yes this is case. I call this the "golden age" of transistors (I.e. specificall discrete transistors) because at this point most vacuum tube stuff was in the rear view mirror and integrated circuits were still fairly rare and what was there was cumbersome to use. Because there were very few ICs everything had to done with and problems solved using transistors.

      As for this specific satellite, you'd think that the tech behind it would be declassissfied. But my guess is that being military it's likely more red tape than worth. All the linear components of the radio system were/are commonly known. The control system is likely a simple state machine so nothing too fancy.

      One way around this is to identify the team members that were on the team that built the satellite. Many times their post docs dealt with the same tech that they were using at work. So their phd thesis' that are sitting on the shelf in the library of their alma matter could very well give a glimpse into the technology used in the satellite.

      All the literature (Especially from the trade rags like EE design) from this era also are very interesting to read. The hobbyist magazines from the era are a blast to read too (and of course easier to understand for beginners).

      To see an "open souce" version of satellite technology of this era, you can see what hams devised with Oscar 7. [wikipedia.org] It's durability should give the reader pause as it does me. Also, if you want to understand satellite control systems from this age you should investigate the RCA 1802 COSMAC microprocessor - that hobbyists are now working to resurrect! You can find an Altoid tin version online. It was commonly used in satellite systems because there was a space rated/radiation hardened version of it that was off the shelf readily available. Both RCA and GE were in the transistor business and a lot of their engineering publications often had hobbyist circuits in them created by engineers "playing" with the tech. As aside, another interesting thing to review is the history of RCA and see how they seemed to lose their way as they tried to be competitive in consumer electronics. See the "technology connections" YouTube channel that does an excellent job of digging into this.

      So even if the schematics for this particular satellite are not readily available, there actually is still a lot of interesting stuff that someone can "geek out" on!

      • by codlong ( 534744 )
        My question is, how the hell is this thing still powered up? I'm assuming it's solar powered, but there must be a battery store for the power, right? Speaking from complete ignorance of the platform, but it's damned impressive they got a signal from such an old device.
        • by guruevi ( 827432 )

          Could be nuclear powered, it's from about that era when we were having nuclear powered cars etc. Those things may be 'dead' as in the electronics it was purposed for are no longer functional but it may respond or send out a control signal. You could also put on a tinfoil hat and say the CIA uses it daily to communicate with its spies.

        • It is solar power. Originally, the design used batteries to ensure continuous operation, but after that system failed due to a short, those became unusable.

          The satellite becomes temporarily usable now whenever the systems have enough power from the sun alone to turn on, but can't stay active through any dark periods.

        • It's entirely solar powered. Except for a 5 year timer powered by a battery that was suppose to turn it off. I guess that didn't work so well. See page 43, https://apps.dtic.mil/dtic/tr/... [dtic.mil] Scott Tilley
        • Hams are still using AO-7, a ham satellite launched in 1974. Almost all satellites are solar powered with batteries to get them through eclipses. AO-7 failed decades ago when its batteries short circuited the power supply. 21 years later the batteries open circuited and the satellite came back to life on solar power only. Hams still use it daily.
    • Re: (Score:3, Insightful)

      by johannesg ( 664142 )

      The lack of comments on this baffles me. If ever there were "nerd news"

      You are confused with the old slashdot, from before it became an activist site that reports exclusively on climate change and UBI.

      • And you are confusing the slashdot of old that reports exclusively on climate change and UBI with the current one occupied by nazi and reddit trolls!

      • Agreed. The last 20 years have not been kind to this place.

        • Relative to the fossil record of an informational web maintained by hobbyists and early adopters, despite all its blinking tags, versus the profit-driven iterations of integral versions serving thin clients, how is any conclusion other than Slashdot thrives not a wildly inured misgiving?
    • by Martin S. ( 98249 ) on Saturday April 25, 2020 @04:03AM (#59988504) Journal

      Because, the Geeks have mostly left. At one time I'd check slashdot for breaking stories several times a day. All the big tech stories broke here. Slashdot was the hub of global technology. We has the /.effect.

      Today, slashdot almost never breaks any stories and is often slow to the table. It is mostly America political trolls.

      This sort of story is a rare bird.

    • Nonsense, us real nerds are just still soldering our mixers and lna's as per the example, to replicate the feat. Some things are worth more than frist psot.
    • by msk ( 6205 )

      It's not an acronym. (If it ever was, and that's debatable, it's not now.)

      So "ham", not "HAM".

    • The lack of comments on this baffles me.

      I've been busy or would have commented on this earlier myself - you are right this is by far the most Slashdot worth story to actually appear in some time!

      Amazing work, and to think that thing is still in stable orbit...

    • by vk2sky ( 1463797 )

      The lack of comments on this baffles me. If ever there were "nerd news", this is it. HAM radio used to be the heart and soul of the "geek" culture, but wow, a satellite that is supposed to be dead that may still be awake? Especially from that early era.

      I wish NPR had asked me for a comment, so I could have pointed them to a lecture at my local radio club on a related topic, in this case *Rescuing ISEE-3 using Software Defined Radio*: https://www.youtube.com/watch?... [youtube.com]

      73

    • Comment removed based on user account deletion
  • Really? (Score:4, Informative)

    by fred911 ( 83970 ) on Friday April 24, 2020 @09:58PM (#59987698) Journal

    "This required the building of an antenna, erecting a new structure to support it. Pre-amps, filters, stuff that takes time to gather and put all together,"

    Hey, real cool that an "amatuer" confirmed operational status of what many assumed was "space junk".

    But, seriously acquiring a 236 MHZ FM signal doesn't require a different antena than the capabilities of a 1.25meter antenna. Building a YAGI and pointing it at where and when you assume signal will be received, does. Aperently the Keps are available https://www.heavens-above.com/... [heavens-above.com]

    The second link in the story is quite descriptive and worthy a read. Can you imagine launching a device without a control link, nor an identifier, designed to spew signal without protocol, now? Better yet, one that is still able to provide signal (without solar power) 52 years later?

    Yep... truely news for nerds.. stuff that matters.

    • Re:Really? (Score:5, Insightful)

      by Strider- ( 39683 ) on Friday April 24, 2020 @10:29PM (#59987758)

      The signal is undoubtedly extremely weak, requiring pretty good low noise amplifier on the receiver. LNAs for 236 MHz aren’t generally available (for a price an amateur would be willing to pay on a lark) so he probably built it himself. Likewise, it was probably more than a 3 element Yagi, so some build work there.

      Lastly, he probably ran CW or SSB through it as the linear transponders on these satellites generally don’t like FM, especially when their power systems are as compromised as LES-5’s is likely to be.

      • Re:Really? (Score:5, Insightful)

        by AmiMoJo ( 196126 ) on Saturday April 25, 2020 @04:09AM (#59988508) Homepage Journal

        According to TFA be build a 6 element Yagi. It's actually a great article/blog post with loads of interesting detail.

        For example he determined that it was LES5 by measuring the carrier frequency drift when the satellite was in a solar eclipse. The sudden change in temperature affects the oscillator and causes the carrier frequency to change in a predictable, easily visible way.

      • The signal is undoubtedly extremely weak,...

        ~Strider-

        Have your teeth checked out.
        Undoubtedly? Real scientific qualifier there, bub. /s

      • He would be listening for a beacon or a downlink. It isnâ(TM)t a ham satellite in a ham band. He wouldnâ(TM)t be transmitting through it.
    • Wait... no solar? So it's RTG-powered?

      The thing that blows my mind it that it's supposedly decommissioned, but nevertheless STILL in a stable geostationary orbit after decades without active stationkeeping. It seems like MODERN satellites can barely hold stable orbits for a few days or weeks at a time without regular stationkeeping, and only last 10-15 years before getting EOL'ed. Just look at the short lives of DirecTV's present constellation, SiriusXM's original molniya constellation (RIP), and the previo

      • It seems like MODERN satellites can barely hold stable orbits for a few days or weeks at a time without regular stationkeeping

        To keep latency down, modern commsats are relatively close to our atmosphere. A molecule here, a molecule there, pretty soon it's a real drag.

        • A molecule here, a molecule there, pretty soon it's a real drag.

          ~sysrammer

          The poster clearly gave example of satellites not so burdened. The classic joke would have been to insult latency, like Bill Murray insulting Sigourney Weaver's baby in Ghostbusters.Do you have something against the character arc, the journey, of Sigourney? Mr. Rammer? Are you wearing a dress? You seem to be wearing the world's address. A real drag.

          • Well, technically, the Sirius modified-molniya constellation spent a few hours per day brushing up against the atmosphere. I suppose in Sirius' case, they just made a business decision to rely on the geostationary satellites + terrestrial transmitters for both Sirius & XM, but IMHO, Sirius had the far more elegant solution because it worked almost everÃwhere & only NEEDED repeaters in valleys & areas with skyscrapers (because, at any given point in time, one satellite was more or less "over

      • Update: did some research. It's solar, not RTG. It only works in direct sunlight... the solar panels still work, but the batteries died decades ago.

        It's presently in a graveyard orbit, not in a geostationary orbit... so it drifts & wobbles.

      • It is not in a geostationary orbit. No abandoned satellite will stay put. LES 5 has an inclination of 2.97 degress and a mean motion of 1.094 revs per day. It is low, at 33185-33616 km compared to 35786 km geostationary altitude. It is drifting north and south, and to the east. It is neither geostationary, nor geosynchronous anymore.
      • A large number of modern satellites are put into Low Earth Orbit, which is not Geosynchronous Earth Orbit. GEO is much further away from the earth; usually the orbit is such that it stays over the same spot relative to the earth. Since there isn't enough atmosphere to cause drag, and GEO, by definition, is an extremely stable orbit, it can stay that way indefinitely. LEO, on the other hand, will eventually decay, and generally the satellite will fall back to the earth. More important, it won't be able t

    • Re: Really? (Score:3, Interesting)

      by N1EY ( 817702 )
      No one seems to point out that this is not UHF. There are stock ham gear for UHF, but I don't know about all of the gear in this range. 237mhz is in that special area that the Military and others fought to keep clear for years. Let's see how many secret satellites are still operating in this range due to the lack of equipment and the obscurity.
      • No one seems to point out that this is not UHF. ... Let's see how many secret satellites are still operating in this range due to the lack of equipment and the obscurity.

        Weird Al, not amused. Monkey House in play.

      • by fred911 ( 83970 )

        "No one seems to point out that this is not UHF."

        Correct. It's VHF and " The spacecraft is emitting 100bps BPSK.". Don't get me wrong here, it's an awesome accomplishment. Most HAMs have 2m, 1.25m and 70cm equipment that was (at one time) used to check in on the local repeater. A significant number of the same also were MARS operators and made "type accepted" modifications to their equipment to not only receive but to transmit (Yaesu was well known for easy modifications).

        In addition, detection a

      • Any decent general coverage receiver covers this band. My elderly ic-r8500 is a prime example.
    • Aperently the Keps are available... Yep...

      ~Fred911

      T-minus (16~clearance~30) from (co-incident)
      Prior to nineeleventy, I was a pal of a graphic designer whose day job was technical manuals for Quark Express, they went on to instruct C-suits at Storage Tek about ordinated pagination for in-house documentation and were treated poorly. They maintained a server at home and an image server at work. Another pal of theirs had the pleasure of a NeXT box they rooted themselves out of. Real skills, like yours. My gift to them was a medical bag with the RedCross insign

    • Always helps to ensure you resonant the antenna for maximum performance and noise filtering. Here's the system presently used to monitor LES-5 https://twitter.com/coastal804... [twitter.com] Here's the dimensions for a tuned 237MHz Yagi using the wa5vjb 'cheap' yagi design: https://twitter.com/coastal804... [twitter.com]
  • by n3r0.m4dski11z ( 447312 ) on Friday April 24, 2020 @10:33PM (#59987770) Homepage Journal

    if you take the time to read the article. That's one skilled amateur...

    Most people can barely change their wifi channel.

    • if you take the time to read the article. That's one skilled amateur...

      Most people can barely change their wifi channel.

      ~n3r0.m4dski11z

      Frenchy version number you have there, an expressionist impressed by animal lovers is a curious caricature. Maybe it takes a poet to distinguish WAN from LAN?

  • by 4wdloop ( 1031398 ) on Saturday April 25, 2020 @12:06AM (#59988084)

    Wow! A lot the electronics still works since they are receiving a BPSK-modulated signal that it transmits. Hope there still exist any more documentation to decode it...Most engineers who design it probably stopped contributing to entropy of universe long time ago, sadly.

    Try this with a cell phone today. The battery will be dead after few years and that's it. (ok maybe not a fair comparison given the design criteria but this is 50+ yr device).

    • Maybe you could compare it with a similarly (but not quite as) long-lived device. A solar powered pocket calculator from the 80s will still work today, as will your original Game Boy. I have a Tandy M100 that still works if you want to limit it to "high end" (for its time) professional hardware. It'll all eventually fry in space though. Discrete components are more resistant to cosmic radiation than non-hardened integrated circuits, so even a consumer device of its time is even more likely to survive in spa
    • by hey! ( 33014 )

      It's those big-ass discrete transistors. I suppose the thing that will eventually bring these dinosaurs down are the capacitors, but I imagine they used pretty high-spec components. When you're building only nine of something and launching them costs millions of dollars you don't try to save a few bucks on components.

      I'm assuming any batteries on these things are long gone, but they would have spec'd plenty of solar power too. Eventually the PV cells will degrade from UV exposure.

      • I was mostly thinking about batteries cycling up and down under load and solar power for 50yrs. And electrolytic capacitors go bad too...It would be interesting to observe the carrier signal long term to see if it disappears when the sat is eclipsed by earth.

        What kind of battery did they use on it?

        • by hey! ( 33014 )

          There's no mention of batteries in the system descriptions I can find, but apparently Ni-Cad would have been typical for the era. If this satellite used Ni-Cad we can think of the battery as a big resistor in parallel with the rest of the systems. LES-8 and -9 used RTGs.

        • I was mostly thinking about batteries cycling up and down under load and solar power for 50yrs. And electrolytic capacitors go bad too...It would be interesting to observe the carrier signal long term to see if it disappears when the sat is eclipsed by earth.

          What kind of battery did they use on it?

          ~hey!

          User # (veteran ~ clearance ~ property-bonded)(33~0~14), I don't enjoy exposing coded IDs, I am following a fail-safe protocol.

        • The batteries will be open circuited after all this time. The satellite will only work while it is in sunlight. And the mil-spec capacitors they use in spacecraft dont generally go bad. These arent off the shelf shinzen specials.
      • It's those big-ass discrete transistors. I suppose the thing that will eventually bring these dinosaurs down are the capacitors, but I imagine they used pretty high-spec components. When you're building only nine of something and launching them costs millions of dollars you don't try to save a few bucks on components.

        I'm assuming any batteries on these things are long gone, but they would have spec'd plenty of solar power too. Eventually the PV cells will degrade from UV exposure.

        ~!hey

        You do shill factorially and bang so. Yeah, this technology that was highly classified in 1967, an advanced form of technology, indistinguishible from...what was said upthread? From a Martin S.? A rare bird. Is a nest of method and no disclosure of the kind you offer is anything other than misdirection. Suppose, imagine, assuming...moving the en-dash one step to the right as Randall Munroe's generation knows to do...

        It's those big ass-discrete transistors. Discreet you're not.

  • this is awesome and also shows the immense advancements in technology.
    what probably filled a complete room and was ridicilously expensive back in the early 70's, can now be build by anybody.

Never test for an error condition you don't know how to handle. -- Steinbach

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