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Engineers investigating NASA’s Voyager 1 telemetry data
- usr1106 4y agoThose systems are older than the 6502, so they must be extremely simple seen from today's complexity. Amazing what one can achieve without complexity. How much technology today gets wasted for no good, like e.g. serving ads.
- formerly_proven 4y agoAccording to Wikipedia, there are actually numerous 16 and 18 bit computers on-board (none of which are µP/MCUs, of course), with around 64K memory and 64MB of tape storage. The data link has a maximum speed of 115 kbps. https://en.wikipedia.org/wiki/Voyager_program#Computers_and_data_processing https://en.wikipedia.org/wiki/Voyager_program#Computers_and_...
- Gordonjcp 4y ago115kbps while it was out as far as Jupiter, and falling off with distance. I can think of a few places where a solid 115kbps would be more than adequate right here on Earth. Consider that this is in the same band as broadcast satellite TV but with a fraction of the power of for example the Astra 2 satellites. Think in terms of looking out for the brake light of a motorbike in orbit around Jupiter ;-)
- rob74 4y agoThey are older, but you have to remember that the 6502 was a low-cost CPU used in home computers, so the hardware on board Voyager is likely a bit more advanced. And it's also worth remembering that an even older computer guided the Apollo capsules to the Moon and back safely...
- KineticLensman 4y agoIf you want a programmer's eye view of the Apollo hardware / software, I recommend Sunburst and Luminary: an Apollo Memoir by Don Eyles. He wrote some of the programmes that landed the Lunar Module and gives a great perspective on how they worked and integrated with the other programmes (like the radar manager) also running on the LM computer and competing for the tiny computational resources available. [Edit] Including how on one mission he developed a software hack that an astronaut had to type in, correctly, or else, in the few minutes between the LM emerging from the lunar far side and reaching the point where a landing burn was initiated.
- xpil 4y agoI am just reading it now and it is better than anticipated.
- vishnugupta 4y agoI’m blown away by this epitome of reliability. This thing is older than me, hurling across the space exposed to all sorts of hostile particles and working as expected. And here I’m struggling to keep a service up for more than a month.
- throwaway_1237 4y agoDid they try unplugging it and plugging it back in?
- tinmandespot 4y agoShame this comment is languishing at the bottom. Updoot
- kingcharles 4y agoCosmic ray bit flip in the code, most likely. Very relevant recent thread: https://news.ycombinator.com/item?id=31016042 https://news.ycombinator.com/item?id=31016042
- high_pathetic 4y agoPretty sure the CRCs are in place.
- alfiedotwtf 4y agoFrom memory, Voyager and other deep space satellites use Reed-Solomon
- johnohara 4y agoLong system commands with a ton of switches usually give pause, requiring at least a couple of reviews before pressing <enter>. Two day turnarounds are a whole other level. Interesting problem nonetheless.
- avidphantasm 4y agoMy guess is that they have one or more simulators to test planned commands on before actually sending them. Interesting problems indeed.
- jzer0cool 4y agoWhere is the data?
- geuis 4y agoThey have data. It's just a bit wibbly.
- jp0d 4y agoI still blows my mind that they designed and built it more than 45 years ago! Kudos to engineers.
- deleted 4y ago[deleted]
- kristopolous 4y agoI presume many of the people working on it now were born after its launch and were children when it took the final pale blue dot photograph
- wiz21c 4y agoIf only my fridge had such a lifetime...
- selectnull 4y agoHow much are you willing to pay for the fridge?
- toast0 4y agoI paid a ton of money for a sub-zero fridge, but it came with a free house. The console is pretty neat, but I can't figure out how or when to input the finishing moves.
- somenameforme 4y agoVeritasium has an awesome video on planned obsolescence here. [1] The problem in many cases isn't that it costs so much more to make products that last, but rather that making products that break is just way more profitable when you can effectively control the market to such a degree that you don't need to worry about some party pooper (1) coming in and making stuff that does genuinely last and (2) gaining significant marketshare. The example of the light bulb cartel that had unquality assurance, spot testing, and a formal structure of fines and penalties for any members who made too long of lasting lightbulbs is just hilariously dystopic. [1] - https://www.youtube.com/watch?v=j5v8D-alAKE https://www.youtube.com/watch?v=j5v8D-alAKE
- gabereiser 4y agoIsn’t V1 past our solar system? Do I remember that right? This is the only craft that we have at those distances. Super curious to see the outcome of this. We know a bit about outside our solar system but have we ruled out the possibility that our understanding is flawed? Not the sensors? Interesting indeed, considering the signal is still strong, it’s still pointing towards earth, everything else seems nominal.
- WalterGR 4y agoBoth are in interstellar space: https://voyager.jpl.nasa.gov/mission/status/ https://voyager.jpl.nasa.gov/mission/status/ Voyager 1 flew beyond the heliopause in 2012; Voyager 2 in 2018: https://voyager.jpl.nasa.gov/mission/interstellar-mission/ https://voyager.jpl.nasa.gov/mission/interstellar-mission/
- freeflight 4y agoWas disappointed to see so many of their systems offline, thinking they broke, but clicking on their status reveals that most of the systems are actually turned off to save power, including; > "Wide-angle and narrow-angle cameras off to save power (Feb. 14, 1990)" One of the last photos Voyager 1 took back then was looking back at Earth as a Pale Blue Dot [0] Makes me wonder if those cameras could be turned back on, in case one of the Voyagers comes across something interesting? [0] https://www.space.com/pale-blue-dot-voyager-1-photo-30th-anniversary.html https://www.space.com/pale-blue-dot-voyager-1-photo-30th-ann...
- ISL 4y agoIt's a power problem. The radiothermal generator's power output decays exponentially. The PBD photo was taken at approximately the last time that the cameras could be used.
- ISL 4y agoThank you for sharing the upper link. It is serially inspiring. Watching the distances crawl up by many miles/second is kinda bonkers, and the 3D view allows the mind's eye to imagine a new pale-blue dot photo that encompasses every planet we've ever known.
- dd444fgdfg 4y agoit's clearly a message from aliens, embedded in the data stream to get our intention. Occam's razor and all that...
- gzer0 4y agoThis seems very likely that there was a flipped bit, considering the high-radiation environment Voyager 1 is in. This happened to Voyager 2 not too long ago, where it was returning invalid and random data. Turns out, it was a bit flip [1]. [1] https://techcrunch.com/2010/05/19/voyager-2-likely-suffering-from-flipped-bit-syndrome/ https://techcrunch.com/2010/05/19/voyager-2-likely-suffering...
- codetiger 4y agoWouldn't it be easy for the team to find out if it was a bit flip issue? Or May be too many bits decided to flip at the same time. :)
- gzer0 4y agoYes, indeed it would be rather easy for them to figure out (and more likely than not, it probably has been resolved, but who knows). NASA also has the burden of generating public support and interest in their projects. NASA will cease to exist if it does not receive financing; the only way to get that funding is for people to vote in representatives who care about this. Stories like this can be crafted in such a way to help drum up public support in addition to coming off "mysterious" or "puzzling" to have a better chance of more coverage. This story serves more than one purpose.
- leejo 4y ago> This happened to Voyager 2 not too long ago, where it was returning invalid and random data. Turns out, it was a bit flip This also happen to the Magellan probe. Larry Wall was at NASA at that time and added the hex and bit string format specifiers to the pack function in perl so they could fix and recover the data: https://github.com/Perl/perl5/commit/24f4b7dabc8 https://github.com/Perl/perl5/commit/24f4b7dabc8
- hedgehog 4y agoEvery time I read about these probes I think about how many of the current team were probably born years after they were launched.
- kubatyszko 4y agoThis so obvious. Aliens figured it out and are spoofing Voyager transmissions.
- luckman212 4y agoJPL is working on decoding the message. So far, it appears to read: From: Mr. Boss, CEO (mr_boss9735@hotmail.com) Hey John, are you busy? I need you to do something for me. Need you to wire some money. Don't call Mary, this is a personal matter for me. I'm not at my desk, so just email me back and let me know when it's done.
- dylan604 4y agoI thought it was more along the lines of "Send more beer"
- aetherspawn 4y agoJohn, I need you to send me some iTunes gift cards. It's highly urgent, so I don't have time to talk about it on the phone.
- shmde 4y agoPeople interested in knowing more about Bitflip. "The Universe is Hostile to Computers" by Veritasium is good video. https://youtu.be/AaZ_RSt0KP8 https://youtu.be/AaZ_RSt0KP8
- AgentOrange1234 4y agoWhy is interstellar space higher radiation? Would have thought most radiation would come from the sun, so as they get farther from that there’d be less…?
- bawolff 4y agohttps://en.wikipedia.org/wiki/Heliosphere https://en.wikipedia.org/wiki/Heliosphere Basically sun both gives out radiation but also keeps it out.
- pengaru 4y ago"As part of the interplanetary magnetic field, the heliosphere shields the Solar System from significant amounts of cosmic ionizing radiation" https://en.wikipedia.org/wiki/Heliosphere https://en.wikipedia.org/wiki/Heliosphere
- reactjavascript 4y agoImagine that even with a warp drive, we are stuck in this little “air bubble” in the ocean
- ggm 4y agoI wonder if a continuous wave signal is part of the science package. It might be the last thing they can reliably send, given it has no digital dependency and is just a tone, at a set frequency (ideally coming of a thermally stable crystal or something) You can do stuff with a continuous wave, analyse the doppler shift, align to it, irrespective of the bitstream. I imagine at some stage, we will lose signal. Do we get radar bounce back? (some early astronomy was about bouncing radar off planets, Robert Buderi talks about it) -The dish, if it stays in some kind of alignment, might reflect enough to be detected.
- Someone 4y ago> Do we get radar bounce back? There may be factor working in the Voyagers favor, but I think that would be quite a challenge. Pluto is 2,376 km in diameter; the main dish of the Voyagers 3.66 m. In frontal area, that’s a factor of over 100 billion, if that dish keeps pointed at earth, which it won’t once power is gone. Pluto is 5 billion km away; Voyager 2 is over three times as far away. Also, reading https://en.wikipedia.org/wiki/Radar_astronomy#History https://en.wikipedia.org/wiki/Radar_astronomy#History, we haven’t bounced radar of Uranus (3 billion km away; diameter 50,000 km), Neptune (4.4 billion km away; diameter 49,000 km) or Pluto yet.
- ggm 4y agoIn 300 years it reaches the Oort cloud. Maybe it can get an airconditioning re-gas, and the windscreen rubbed by an old newspaper then.
- dTal 4y agoSome back of the envelope calculations on diffraction limits suggests that we'd be very lucky to get 10^-18 of our transmitted energy back, even if we used the entire planet as a transceiver dish and Voyager was a perfect reflector. I would put this into the "very, very impossible" category.
- Nition 4y agoCrossing over out of the Slow Zone and into the Beyond might cause this sort of interference.
- duskwuff 4y agoDon't be silly. All the best zonographers on the Net say Old Earth is deep in the Slowness. A probe would take thousands of years to reach a boundary.
- ISL 4y agoIt is so cool that we have functioning instrumentation almost a light-day away from Earth.
- pengaru 4y agoIt's also rather depressing how long it's taken to get something a mere light-day away from Earth, when so much interesting stuff is many light-years away.
- fy20 4y agoThe launch vehicle of the Voyager probes could carry 15,000kg to LEO, the Falcon Heavy can carry 63,000kg. If we really wanted to send something out as fast as possible, we could do it much faster than this.
- Denvercoder9 4y agoVoyager did benefit of gravity assists from all the major planets, though. New Horizons was launched at a much higher speed than the Voyagers, but will never overtake it.
- accrual 4y agoAlpha Centauri is 4.367 light years away, so at least not too many. :)
- ISL 4y agoThe Arecibo Message is 48 light years from Earth, moving one light-year per year. https://en.wikipedia.org/wiki/Arecibo_message https://en.wikipedia.org/wiki/Arecibo_message
- jtchang 4y agoI wonder if we will ever get a chance to retrieve our probe. Or maybe some kind soul will return it.
- withinboredom 4y agoCheckout the “Backyard Starship” series where the characters basically travel the galaxy hunting for stolen relics (among other things).
- mauvehaus 4y agoIt might be best if nobody tried to return it: https://en.wikipedia.org/wiki/Star_Trek:_The_Motion_Picture https://en.wikipedia.org/wiki/Star_Trek:_The_Motion_Picture
- richardfey 4y ago> Launched in 1977, both Voyagers have operated far longer than mission planners expected, and are the only spacecraft to collect data in interstellar space. Why haven't we launched more since they proved so useful?
- changoplatanero 4y agoIsn’t it also true that these were launched during a special window in time when the planets aligned in such a way that made for a favorable trajectory?
- accrual 4y agoThat's exactly correct. The alignment allowed the spacecrafts to fly by the major planets using gravity assists and minimal fuel for corrections. Both Voyagers launched in 1977. The alignment occurs every 175 years, so 130 years to go to the next one (~2152). https://en.wikipedia.org/wiki/Grand_Tour_program https://en.wikipedia.org/wiki/Grand_Tour_program
- hericium 4y agoIt's just science. It doesn't fill anyone's pockets quick enough to be an incentive.
- ISL 4y agoWe have: https://en.wikipedia.org/wiki/New_Horizons https://en.wikipedia.org/wiki/New_Horizons
- rob74 4y agoI just realized that Voyager 1 took 45 years to get to less than one light-day from Earth. Which is still a huge distance, but it just puts into perspective how daunting the task of covering several light-years with a spacecraft really is...
- abhishekjha 4y ago>it just puts into perspective how daunting the task of covering several light-years with a spacecraft really is... And then you have multipliers like million/billion. I kinda just lose perspective over there.
- MauranKilom 4y ago"'The light from those millions of stars you see is probably many thousands of years old' is a rare example of laypeople substantially OVERestimating astronomical numbers." https://xkcd.com/1342/ https://xkcd.com/1342/ There is plenty of interesting stuff within ten light years, so don't lose perspective too much ;)
- ceejayoz 4y agoDepends how you look at it, I suppose. There are about 5k visible stars, most indeed pretty close... but if you manage to make out Andromeda, I suppose you're technically seeing about a trillion, and they're all pretty far off...
- knorker 4y agoOn the flip side of this in "only" something like 20'000 years it'll be a light year away. Yes, that's a really long time, but 20'000 years ago humans already existed. In fact it's "only" 10% back into the history of humans. This gives me hope that actually while yes out of reach of humans, not out of reach of humanity. Even without FTL. Or in other words: There will be humans out there for whom it's normal that we have sent equipment a light year away. (I choose to believe we'll survive that long)
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- tdiff 4y agoI wonder how do they manage to maintain rather precise orientation of antennas for such a long time. Probably they don't have much power to steer the antennas.
- MarcelOlsz 4y agoAny proper hardcover books with cool technical illustrations and photos about the Voyager 1?
- jeffrallen 4y agoHang in there, Voyager 1! We're rooting for you!
- leokennis 4y agoSome days I think: I’m working on some cool stuff at my job, look how neat! But today I know I’ll never work on a project as cool as interacting with hardware at the edge of our solar system.
- andai 4y agoNever say never ;)
- rightbyte 4y agoNice to see "telemetry" used for actual telemetry and not spyware data gathering.