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Antique Voyager Technology

kdawson posted more than 6 years ago | from the spinning-tapes-and-flashing-lights dept.

NASA 293

sea_stuart writes with a story from the Tidbinbilla space tracking station, outside Canberra, Australia. It is still communicating with the two Voyager spacecraft 30 years after they were launched and 18 years after Voyager 2 passed close by Neptune. Here's a little background on Voyager 1 and Voyager 2. "The bank of computers that would look at home in black-and-white episodes of Doctor Who cannot be junked... [T]he 1970s hardware is now our world's only means of chatting with two robot pioneers exploring the solar system's outer limits. Today Voyager 1 is humanity's most remote object, 15.5 billion kilometers from the sun. Voyager 2 is 12.5 billion kilometers from it. Both continue beaming home reports, but now they are space-age antiques. 'The Voyager technology is so outmoded,' said Tidbinbilla's spokesman, Glen Nagle, 'we have had to maintain heritage equipment to talk to them.'"

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I've got an old dell they can use... (5, Insightful)

DragonTHC (208439) | more than 6 years ago | (#20439067)

Is it really that impossible to run these machines inside an emulator on a modern server?

I can still play my atari 2600 games on my xbox.

Re:I've got an old dell they can use... (4, Insightful)

QMalcolm (1094433) | more than 6 years ago | (#20439079)

This is a total guess, but I'd think that just communicating with something like Voyager 1 would rely on lots of funky old hardware. I mean, the thing is 15 BILLION kilometers away, it's not quite the same as dumping a 2600 cart.

Re:I've got an old dell they can use... (1)

DragonTHC (208439) | more than 6 years ago | (#20439101)

and yet I don't think it would be a problem for modern software or hardware.

how much computing resources did they have in the late 70's at nasa?

less than my desktop PC has now.

Re:I've got an old dell they can use... (4, Insightful)

Anonymous Coward | more than 6 years ago | (#20439141)

and yet I don't think it would be a problem for modern software or hardware.
I think he was thinking more about analog components like amplifiers or something which might be unusual. It's not always all just bits.

That said, I think the real reason isn't that it's not possible to duplicate with modern technology (it is, of course; anything we could have built then, we can build now), it's just that producing a new system just to communicate with Voyager would probably cost more than maintaining what we've got now. Especially since any new system would likely have unforeseen bugs in it, which could possibly result in loss of communication with the space craft (imagine accidentally sending a command which orders the Voyagers to point their radio antennas away from Earth).

Still, it's a bit like the ridiculous argument that some day we won't be able to read CD-ROMs, because the technology will have advanced so far, the hardware will no longer exist. Well, yes, maybe. But scientists will always be able to build something that can scan the surface of a CD-ROM, and decode the data there. But it might not be very economical (though I doubt it; a binary infrared laser scanning device is pretty dirt simple). There's a big difference there between what's economically and technologically unfeasible.

Re:I've got an old dell they can use... (5, Insightful)

arth1 (260657) | more than 6 years ago | (#20439365)

The problem isn't that a new computer can't emulate the software, it's more that it (a) can't do it out of the box and (b) can't emulate the hardware. If you, say, need a 75/1200 baud serial connection to connect to the tranceiver, it doesn't help that USB or Firewire is much faster. And where do you find a 75/1200 serial connector card for a PC? And how's your PC's EBCDIC character set support, for that matter?
If you have to design both the hardware and the software, it's going to be expensive. Not to say untested. And with the probes being where they are, it's not like you get a second chance if there's a bug. Things have to work perfectly, every time. You'd have a hard time convincing anyone that your emulation would be perfect enough to replace something that's aced the test of time for 25 years.

Re:I've got an old dell they can use... (3, Insightful)

Pseudonym (62607) | more than 6 years ago | (#20439567)

And where do you find a 75/1200 serial connector card for a PC?

Give me a week and a modern microcontroller and I'll build you one. Someone else can write the driver.

Re:I've got an old dell they can use... (1, Funny)

Anonymous Coward | more than 6 years ago | (#20439775)

What do you need a week for? This is a days job.

Re:I've got an old dell they can use... (1)

ajlitt (19055) | more than 6 years ago | (#20439929)

Do any modern micros even support divisors large enough to generate all the weird speeds from 75 to 1200? I'll quote "small FPGA and a week" and you can keep your old USB to serial adapter and driver.

Re:I've got an old dell they can use... (2, Insightful)

nurb432 (527695) | more than 6 years ago | (#20440147)

Ok, so run them in parallel for 10 years. Its not like there is a hurry here.

And since you seem to hik we cant create 'new', what happens when one of the old ones die and we cant repair it due to its age? At least if we have tried to replicate the functions with modern equipment we have a chance.

Cost is relative, in this case.

Re:I've got an old dell they can use... (2, Funny)

joeava (1147727) | more than 6 years ago | (#20439129)

The problem is in the remote end.

Re:I've got an old dell they can use... (1)

nyctopterus (717502) | more than 6 years ago | (#20439143)

Well, they'd have to employ someone to write the software and reconfigure the hardware to do it. Chances are it costs them next to nothing to keep the old stuff running. And anyway, maybe they like it for sentimental reasons (pretty much the same reasons we're still listening to the Voyagers I should think).

Re:I've got an old dell they can use... (2, Interesting)

Propagandhi (570791) | more than 6 years ago | (#20439321)

To keep them humming, Tidbinbilla relies on its most experienced engineers, including John Murray, who will have been working there for 40 years on Monday. His colleague Ian Warren has knotched up 42 years in the space business.

Not that TFA can be trusted (honestly how would something be "too slow" for a computer? Does my processor get impatient?) but it kinda implies that these guy's primary responsibility is this computer. For the price of two senior engineers it really seems like they could cook up a modern replacement.

Seems odd that they don't just salvage the analog components and connect it to a modern computer... I guess I'd understand not touching it if it's deemed fragile...

Anyone know if the Voyagers rely on a heartbeat or something? If it's just a receiver I can't see why building a modern backup isn't worthwhile.

Re:I've got an old dell they can use... (4, Insightful)

Zarhan (415465) | more than 6 years ago | (#20439381)

Anyone know if the Voyagers rely on a heartbeat or something? If it's just a receiver I can't see why building a modern backup isn't worthwhile.

They do. First, take a look at

http://voyager.jpl.nasa.gov/mission/weekly-reports /index.htm [nasa.gov]

Namely (of the latest one):

Voyager 1 command operations consisted of the uplink of a command loss timer reset on 08/04 [DOY 216/0135z] and CCSL A064 on 08/06 [DOY 218/0236z]. The spacecraft received all commands sent and the CCSL was verified.

Voyager 2 command operations consisted of the uplink of a TLMPRG and a command loss timer reset on 08/06 [DOY 218/1329z]. The spacecraft received all commands sent and the Telemetry Purge proceeded nominally per predicts.


So yeah, they are still uplinking stuff - mostly just command loss timer resets.

What happens if they don't send the timer reset? Well, see

http://voyager.jpl.nasa.gov/science/thirty.html [nasa.gov]

If the timer reaches zero, as a result of a command not being received by the spacecraft within the programmed six week duration, the command loss timer will have expired and the Command Loss (CMDLOS) routine will be activated which leads to the initiation of the BML.

The implementation of BML-7 (the seventh BML to be loaded on-board Voyager 2), in conjunction with the baseline sequence, provides this automated protection against loss of command capability. BML-7, with some differences in implementation for the two spacecraft, is loaded on-board both Voyager 1 and 2.

So yeah, if receiver on V-ger gets broken, or the transmitter down here on earth, the ship can continue to still send data down here in a completely autonomous fashion. However, a remote capability is probably a good idea to have if something interesting comes up.

(The link has more details what the "BML" entails).

Awesome (4, Interesting)

KlaymenDK (713149) | more than 6 years ago | (#20439603)

Whenever I come across news about the Voyagers, I generally dig deep and read a lot. I am utterly in awe -- of the spacecraft themselves, that they are still functioning, that they are so mind-bogglingly far away, and that humans have created them with the tools of their time. Wow. The link you posted shows in what incredible detail the mission was thought through.

I am very glad that there are still people who monitor and maintain the Voyagers. They deserve it.

Re:I've got an old dell they can use... (2, Insightful)

Kjella (173770) | more than 6 years ago | (#20439881)

So yeah, they are still uplinking stuff - mostly just command loss timer resets.

And there's the #1 reason not to touch this system already. Both probes have left the solar system and entered interstellar space. There's something like ~70000 years to the next star system. We're not expecting them to find anything, and if they did the direction they're going is probably as good as any. Right now it's just the record for "most distant object we've held communication with", so don't mess with it. Is it seriously that big a problem to keep the system going here on earth when you manage to keep it going in outer space? Ir's not like we need to upgrade it for any reason, it's basicly living its own life together with the Voyager probes, like a small bubble of the 70s. Worst case the hardware completely breaks down with no spares and we have to just listen to it, which is what we do already (I assume we can do that with more modern equipment). So where's the upside of moving to a newer system?

Re:I've got an old dell they can use... (3, Interesting)

Ash Vince (602485) | more than 6 years ago | (#20439421)

I studied Space Tech for a while so while this is still a guess I like to think it a fairly educated one:

In order for something to be acceptable to NASA for use in the space program it has to be very thoroughly tested. This means you could write a software emulator that did everything required, but then it would have to run flawlessly for 10 years in order to be approved for use. You have to remember that these computers can also send commands to the satellites, so if they crash and send an erroneous command out, then that command will be actioned by the satellite.

I know this is highly unlikely, but it is not impossible so why risk it when the result of that one command could be that we lose both satellites for ever.

There is a mantra when it comes to dealing with any computer system that is running a mission critical app:

"If it ain't broke, don't fix it."

I would suggest that anyone wanting to be sysadmin, learn this. There are times when it doesn't apply but that is usually when the benefit of change out way the risks. In this case what is the benefit of upgrading the system at our end?

Re:I've got an old dell they can use... (1)

Peet42 (904274) | more than 6 years ago | (#20439501)

It would be good if they were to build a modern receiver though, that they could run in tandem with the legacy equipment to allow them to carry on receiving in the case of a catastrophic failure.

Re:I've got an old dell they can use... (1)

Ash Vince (602485) | more than 6 years ago | (#20439517)

I expect they probably have, but they will still keep the old two way link going for as long as possible.

Re:I've got an old dell they can use... (1)

Aenoxi (946506) | more than 6 years ago | (#20439563)

I'm intrigued by a thought that occurred when reading your post. Do Voyager I and II still count as "satellites" given that they have achieved escape velocity from the solar system?

Re:I've got an old dell they can use... (1)

QuickFox (311231) | more than 6 years ago | (#20439749)

Do Voyager I and II still count as "satellites" given that they have achieved escape velocity from the solar system?
That's an interesting question! For all you youngsters who don't know this, the word satellite originally meant a body circling a planet. I think the meanings of these words have shifted, so that nowadays a body circling a planet is called a moon, and the word satellite stands for a more-or-less autonomous machine in space.

But I think both words are sometimes used in this new sense and sometimes in their old sense.

Re:I've got an old dell they can use... (5, Funny)

gone_bush (578354) | more than 6 years ago | (#20439435)

No can do - the licence specifically prohibits running the software in a virtual machine.

Re:I've got an old dell they can use... (4, Insightful)

mrmeval (662166) | more than 6 years ago | (#20439443)

You are stepping into the twilight zone of the military industrial complex/government procurement system.

An existing system that works has gone through the bowels of this system and been sanctified.

It would take as much money to re-engineer it as it does to maintain it. It is an annoying fact that getting money to fix something in either the military or government is easier than getting something new even if the new item would save money. This is one of the reasons several of the systems I've worked on were 20+ years old. The anti-mortar Firefinder radar being used in Iraq was designed in the seventies and finally approved and deployed in the 80s and is still in use today.

There are plans to replace it but right this instant they need them in the field so it costs much more to refurbish one than to buy either a 'newly' made one which is intended for foreign sales and is not authorized for procurement or procure the newest model.

Currently the latest and greatest is rumbling around the guts of the system and some prototypes were fielded in 1998 so expect them to be finalized in 2008 and accepted later....

I wish I could point and say "graft and corruption" but it's fighting that which has led to our current procurement system. It's not ever going to be perfect but it does help to keep sawdust out of MREs.

Re:I've got an old dell they can use... (2, Interesting)

jamesh (87723) | more than 6 years ago | (#20439491)

It would take as much money to re-engineer it as it does to maintain it. It is an annoying fact that getting money to fix something in either the military or government is easier than getting something new even if the new item would save money.


I'm sure you understand why... I think the conversation would go something like this:

IT: "This new system will cost $1bn, and will save $3bn/year in maintenance on the old system".
Management: "The previous system was supposed to cost $1bn to develop, and ended up costing $10bn. If I sign off on this it will be my ass on the line when the budget blows out, so I'll stick with known quantities thanks."

Re:I've got an old dell they can use... (0)

Anonymous Coward | more than 6 years ago | (#20440131)

Not at all close. O&M (operations and maintenance) money comes from a different pot of money then does buying systems, or developing systems. You read that right, developing systems is a different pot of money then buying systems. That means that there are things for which the money exists to buy, but development money ran out, and it also means that we're developing things for which there's no money to buy. It's stupid, but it's not just NASA and the military, it's the stupid, congressionally written Federal Acquisition Regulations.

John

Re:I've got an old dell they can use... (2, Insightful)

PetraData (1135825) | more than 6 years ago | (#20439461)

This assumes that:

(a) they have the source code
(b) the source code is not too obfuscated from 1970s engineering paradigms that it can be understood
(c) the guy who originally wrote the system is not dead so that they can talk to him about all the eccentricities of it
(d) that it isn't too bulky to cause a slowdown on NASA's emulators when dealing with real time communication
(e) there is no funky encryption built into the system to protect it from the Soviets

In terms of cost/benefit analysis, it's probably just cheaper for them to leave the old equipment running than pay millions for consultants to take a look at how to port a 1970s communication system built at the height of the Cold War ... to Windows.

They have the source code and the architecture (3, Insightful)

Qbertino (265505) | more than 6 years ago | (#20439557)

The reprogrammed Voyager 2 to send color pictures while it had been en route for 15 years allready. Mind you, they reprogrammed Voyager 2 to send *color pictures* made with a system that was built to make b/w pictures. Using a single digit amount of registers to push single bits around a 30 year old computer that has less oomph than todays cheapest calculators aboard a space probe that is a kazillion-billion miles away is quite a stunt. Let alone updating the OS this way to generate color images.

I think these guys know what they are doing and if they choose to keep the old equipment running in order to communicate more relyably with the Voyagers, I trust they have perfectly valid reasons for it. And no, an off-the-shelf Dell is most probably not a feasable replacement. No matter how powerfull it is.

Oh, and by the way: A modern computer would drain voyagers batteries so fast, they'd be dead in a few hours. My old Sharp 1403 H Pocket Computer, built with technology from the early-to-mid 80s runs 200+ hours under full load on a pair of button-cells. I haven't replaced them in 10 years and it still runs on them. I have yet to find a modern handheld computer that can do this.

Re:I've got an old dell they can use... (1)

Dunbal (464142) | more than 6 years ago | (#20439657)

(a) they have the source code

      You do realize that the RIAA and MPAA's plan to cover the holes in the punch-cards to prevent piracy was a drastic failure, don't you? Of course they have the source code! How many boxes of it do you want?

Re:I've got an old dell they can use... (1)

mikerubin (449692) | more than 6 years ago | (#20440075)

Is that what happened in Florida with the 'chads'

Re:I've got an old dell they can use... (1)

Nazlfrag (1035012) | more than 6 years ago | (#20439781)

Bloody programmers, forever reinventing the wheel...

Re:I've got an old dell they can use... (1)

Gordonjcp (186804) | more than 6 years ago | (#20439915)

Is it really that impossible to run these machines inside an emulator on a modern server?

Yes. Yes it is. An emulator cannot capture all the subtleties of the real hardware. Every little quirk would have to be duplicated, even the ones you don't really know about.

If it was possible, don't you think they'd be doing it?

Junked? (-1, Troll)

speaker of the truth (1112181) | more than 6 years ago | (#20439083)

I thought this stuff was state of the art for those backward hicks?

Useful information? (1)

Shifty Jim (862102) | more than 6 years ago | (#20439099)

First off, I think it's amazing that we're still able to communicate with these space-age relics, it's just incredible.

That being said, while they're obviously a long, looong way out there, with their ancient instruments and our antique equipment, are they really giving us any sort of information that we either don't know already or can't glean easier with newer technology?

Re:Useful information? (0)

Anonymous Coward | more than 6 years ago | (#20439123)

They're the only working space craft outside of the solar system. They're still giving magnetic and other data. Sure, you can postulate and look at the area they're in, but you really don't know whats happening without actually putting an instrument there and taking data.

Re:Useful information? (3, Informative)

fr4nk (1077037) | more than 6 years ago | (#20439149)

From the Wikipedia article [wikipedia.org] :

If Voyager 1 is still functioning when it finally passes the heliopause, scientists will get their first direct measurements of the conditions in the interstellar medium.

Re:Useful information? (1)

Maelwryth (982896) | more than 6 years ago | (#20439531)

Yes. The information is that you can go that far. We assume that you can. Until we try it, we don't know.

Re:Useful information? (5, Funny)

QuickFox (311231) | more than 6 years ago | (#20439807)

Yes, the science community will be rather surprised when the Voyager spacecraft smash into the huge black sphere with the painted stars.

Functional replacement with modern components? (1)

Mostly a lurker (634878) | more than 6 years ago | (#20439125)

I can well imagine that just running an emulator on modern equipment would be inadequate as the whole peripheral interface is likely incompatible with current standards. However, I am at a loss to understand why they cannot just reimplement the current setup using modern and more reliable components. It must cost a fortune to maintain such old computers and, according to TFA, they want to keep them running for well over 10 more years.

Re:Functional replacement with modern components? (3, Interesting)

MichaelSmith (789609) | more than 6 years ago | (#20439221)

It must cost a fortune to maintain such old computers

Not really. As long as you have people who understand the hardware and a supply of old machines for spare parts you should be able to keep things ticking along for decades.

In my last job we ran the entire Melbourne traffic signal system off PDP 11/84's and 83's. Its a good way to keep your wire wrap skills up to scratch.

Re:Functional replacement with modern components? (1)

unfunk (804468) | more than 6 years ago | (#20439343)

Ah.
So that explains Melbourne drivers then... :D

Re:Functional replacement with modern components? (1)

MichaelSmith (789609) | more than 6 years ago | (#20439373)

So that explains Melbourne drivers then

It must :)

The same software SCATS (Sydney Coordinated Adaptive Traffic System) is used in Adelaide and Sydney as well as a few places in other countries.

Re:Functional replacement with modern components? (5, Funny)

unfunk (804468) | more than 6 years ago | (#20439409)

The same software SCATS

That sounds like some pretty shitty software...

Re:Functional replacement with modern components? (1)

Gordonjcp (186804) | more than 6 years ago | (#20439951)

In my last job we ran the entire Melbourne traffic signal system off PDP 11/84's and 83's

There are still thousands (yes, really thousands) of QBus PDP-11s in embedded hardware kicking about. Ventilation systems, process control, all sorts of stuff.

I've seen a T11 chip (basically a PDP-11 without memory management or hardware floating point) used in an engine management system in a car, dating from about 1982. The whole unit was about the size of a telephone directory.

Re:Functional replacement with modern components? (0)

Anonymous Coward | more than 6 years ago | (#20439329)

Wouldn't it cost more to rebuild the entire system? How long would it take? Are all of the specifications still known? Why rebuild when the current system seems to be working fine. I don't think they would want to take the current system down to reverse engineer if it came to that.

Re:Functional replacement with modern components? (1)

unfunk (804468) | more than 6 years ago | (#20439361)

I don't think they would want to take the current system down to reverse engineer if it came to that.

Exactly. If it ain't broke, don't bloody well fix it!

*pats his 386*

Re:Functional replacement with modern components? (1)

Antique Geekmeister (740220) | more than 6 years ago | (#20439481)

Have you ever tried to backport software to a previous operating system release? Simply finding the documentation and the backups and installation media, then being able to read it is a major issue. I've actually seen old software lost, from my undergraduate days, because there weren't any readers available to recover it.

Go ahead: find an 8 1/" floppy drive that still works, or a paper tape reader. Finding the set of Rosetta stones to understand such old hardware and convert its capabilities to modern work is a serious, serious problem. It actually helps pay my salary when I come across old projects and upgrade them to new software.

Re:Functional replacement with modern components? (1)

RAMMS+EIN (578166) | more than 6 years ago | (#20439509)

``However, I am at a loss to understand why they cannot just reimplement the current setup using modern and more reliable components.''

Because modern components aren't more reliable?

Re:Functional replacement with modern components? (0)

Anonymous Coward | more than 6 years ago | (#20439515)

an emulator running on modern equipment would be orders of magnitudes less reliable than what they have now due to the increased parts count.

mtbf is inversely related to the number of parts in your system.

It's Alright... (3, Interesting)

VE3OGG (1034632) | more than 6 years ago | (#20439139)

Even after being flung across the solar system, I am sure Captain Janeway will find a way to repolarize the deflector dish to emit a warp bubble that combined with future Borg technology and that from Species 4971, some old fashioned ingenuity, a transwarp generator, a friendly if dull-witted Talaxian, a half-human half-Klingon baby, a group of Maquis rebels, a hot-shot pilot who doesn't give a damn for regulations, and a hot Borg in a skin-tight leotard will be able to make it back, and the ship will probably be in better condition then when it left!

I'm sorry... I'm bitter...

Re:It's Alright... (1)

zzottt (629458) | more than 6 years ago | (#20439171)

bravo!

Re:It's Alright... (1)

Antique Geekmeister (740220) | more than 6 years ago | (#20439493)

Just have Voyager broadcast pictures of the hot babe in the skin-tight outfit. Some /. fanboy will break the 30 year-old DRM in a matter of moments, although Voyager will crash from the download traffic.

Science for the man on the street (0)

Anonymous Coward | more than 6 years ago | (#20439157)

This is an interesting story, but there's a bit too much of the usual dumbing down of the details for the popular media.

One of the analogies used in the article is just plain nonsense: "When [the signal] reaches us it's 20 billion times weaker than a watch battery." Since when is "a watch battery" a measure of power? I'd like to know how many picowatts that is.

Also, the main difficulty in reciving and decoding the signals is probably that they use advanced (for the time) error-correction codes. This coding and decoding could probably be duplicated with modern equipment, but I suspect that it's more a question of spending the money.

Re:Science for the man on the street (2, Informative)

pv2b (231846) | more than 6 years ago | (#20440157)

Let's assume (assumption number one) they mean the voltage of the received signal in the antenna is 20 billion times weaker than a watch battery.

Now, a watch battery is approximately 3 volts in voltage, if I recall correctly. 3 / 2e10 == 1.5e-10 V -- so if that's what they meant by signal strength, they're getting a voltage of 150 picovolts somewhere in the antenna.

P = U^2 / R. If we assume (assumption number two) they've got their antenna matched to 50 Ohm wherever they connect their antenna to their equipment. (1.5e-10)^2 / 50 = 4.5e-22 W == 450 yoctowatts. (That, incidentally, is also how far down the SI prefixes go. :-)

You wanted to know how many picowatts that is... well, that's 4.5e-10 picowatt -- or -184 dBm. This is probably the power they get in their connector after their antenna.

Or, in other words, 20 billion times weaker than a hypothetical watch battery that emits a RF signal at 3 Volt transmitting into a 50 ohm antenna. ;-)

This, of course is assuming that's what they meant. They could have meant something else arbitrarilly entirely.

Any real info on the systems used? (0)

Anonymous Coward | more than 6 years ago | (#20439169)

I'm a history junkie and love to read about old systems and such. Is there anything out there technical info about these computers, and possibly pictures?

32 bits a second (3, Interesting)

Nymz (905908) | more than 6 years ago | (#20439187)

FTA

That is because the ageing probes can only chat at a sluggish 32 bits a second, far too slow for modern computers.

(32 bits) x (60 seconds) x (60 minutes) x (24 hours) x (365 days) x (30 years) = (30,274,560,000 bits)
(30,274,560,000 bits) / (8 bits) / (1024 bytes) / (1024 KiB) / (1024 MiB) = (about 3.5 GiB over 30 years)

I don't think a modern computer would help, because it's clear that Comcast is seriously throttling their torrent connection.

Re:32 bits a second (2, Funny)

tehSpork (1000190) | more than 6 years ago | (#20439227)

The Voyager probes are 15.5 and 12.5 billion kilometers from the sun and Comcast can connect to them, yet still couldn't get a connection out to my house in relative suburbia until a couple years ago?

I call BS.

Re:32 bits a second (1, Informative)

Anonymous Coward | more than 6 years ago | (#20439613)

Actually, they haven't been using 30bps all the way. The transmit rate has been reduced due to the decreasing signal power that is received at earth, but maybe also due to the reduced power output of the RTGs, but have been able to increase it from the planned rates due to upgrades to the receiving equipment.

At Saturn, they were transmitting at 115200 bps, at Jupiter 44800bps, 29900bps at Neptune and 21600bps at Uranus. There are multiple different transmit modes, with varying power requirements and different receiver requirements. The high rates given above were only possible by combining multiple antennas, so in cruise mode, they have to make do with much lower data rates. There's more documentation here [nasa.gov] , and, while I haven't found anything about the ground station computers that are used, here's an interesting article about the onboard computers of the voyager spacecraft [nasa.gov] .

Cost benefit analysis (2, Insightful)

Colin Smith (2679) | more than 6 years ago | (#20439191)

Seems like nobody's done one for the costs of hiring a couple of engineers to reverse engineer or re-implement the protocol...

 

Re:Cost benefit analysis (1)

Onlyodin (1137597) | more than 6 years ago | (#20439271)

Anyone heard of VMWare? Their products help virtualise old systems :P

They have a freebie product too!

Re:Cost benefit analysis (2, Insightful)

arth1 (260657) | more than 6 years ago | (#20439387)

More likely, they have done just that, which is exactly why this runs on legacy hardware and software.

(The definition of legacy is "something that works".)

What about this requires old equipment? (1)

general_boy (635045) | more than 6 years ago | (#20439235)

Either there's something they're not telling us, or the reporter may be clueless.

A 32bps data stream is plenty slow alright, but if anything, modern equipment should be able to do a better job at plucking the oh-so-faint signal out of the noise.

Re:What about this requires old equipment? (3, Insightful)

Detritus (11846) | more than 6 years ago | (#20439297)

The reporter is clueless. It's all a matter of money. It's very expensive to take an old piece of software, written in some obscure language, running on an old machine with a weird architecture, reverse engineer the requirements, rewrite it for a modern machine, and debug and test it thoroughly. You need people who understand the old system and the environment that it ran in. It's usually much cheaper to keep the old hardware running. Plus, many older systems were custom designs, optimized for a particular task, and can still do a better job than more generic modern hardware.

Re:What about this requires old equipment? (0)

Plunky (929104) | more than 6 years ago | (#20439389)

The reporter is clueless. It's all a matter of money. It's very expensive to take an old piece of software, written in some obscure language, running on an old machine with a weird architecture, reverse engineer the requirements, rewrite it for a modern machine, and debug and test it thoroughly. You need people who understand the old system and the environment that it ran in. It's usually much cheaper to keep the old hardware running. Plus, many older systems were custom designs, optimized for a particular task, and can still do a better job than more generic modern hardware.

Ok, here is an idea then.. open source. Yes, there are thousands of geeks out there who, if the protocol was simply published, would write that software for the pure pleasure of it.

I didn't read TFA, but TFS said they were 'tracking faint whispers' which would make it a one way street I guess, is there any way to control these spacecraft remotely that would be not safe to publish?

Re:What about this requires old equipment? (3, Insightful)

jamesh (87723) | more than 6 years ago | (#20439503)

Ok, here is an idea then.. open source. Yes, there are thousands of geeks out there who, if the protocol was simply published, would write that software for the pure pleasure of it.

Failing that, you'd put the software under the DMCA and claim that it was the hd-dvd encryption algorithm. You'd have three different OSS solutions in a week.

but would they do a proper job? (1)

fantomas (94850) | more than 6 years ago | (#20439645)

Yes, there are thousands of geeks out there who, if the protocol was simply published, would write that software for the pure pleasure of it.

Looking at the number of v0.1 projects that are fossilised and not moving on sourceforge you can understand the astronomers concern that this might not be the most reliable way forwards... open sourcing might draw in a wider crowd (and I agree it would be a good thing to do) but that in itself won't assure you of a reliable piece of code being created.

Re:but would they do a proper job? (1)

Plunky (929104) | more than 6 years ago | (#20439703)

Well, publishing specs may or may not produce something, but its a better chance than not publishing anything I would think..

Re:What about this requires old equipment? (1)

Detritus (11846) | more than 6 years ago | (#20439477)

Open source is not some magic wand that solves all problems. Besides knowing how to program, it takes at least several years of full-time experience in a very specialized field before someone can be expected to produce useful software.

Re:What about this requires old equipment? (1)

QuickFox (311231) | more than 6 years ago | (#20439997)

Open source is not some magic wand that solves all problems.
How dare you!

Re:What about this requires old equipment? (0)

Anonymous Coward | more than 6 years ago | (#20439485)

It would be sad if the equipment were to fail and contact is lost permanently. Though if you think about it, it would be kind of funny. Just think, wouldn't be ironic, after sending these probes into the most dangerous region known to mankind and survive innumerable hazards, just for contact to be lost, not by them, but by us?

Re:What about this requires old equipment? (1)

Dunbal (464142) | more than 6 years ago | (#20439631)

It's very expensive to take an old piece of software, written in some obscure language, running on an old machine with a weird architecture

      However this is countered by the fact that the entire program is probably only 4kB...

Re:What about this requires old equipment? (2, Insightful)

Detritus (11846) | more than 6 years ago | (#20439673)

You underestimate how much a clever programmer can do with 4kw (kiloword) on many of these systems. These programs can be very complex and difficult to understand, even with the source code.

Pictures (0)

Anonymous Coward | more than 6 years ago | (#20439259)

Is there any pictures of the hardware? I'm curious what the old monsters look like

Re:Pictures (1)

fr4nk (1077037) | more than 6 years ago | (#20439375)

The NASA-Site has some pictures [nasa.gov] of the probe during assembly.

Re:Pictures (1)

MichaelSmith (789609) | more than 6 years ago | (#20439465)

I think he means the ground hardware

Re:Pictures (0)

Anonymous Coward | more than 6 years ago | (#20439717)

Yea I meant the computers, pics of the Voyagers can be found anywhere.

Re:Pictures (2, Informative)

Whiteox (919863) | more than 6 years ago | (#20440163)

Pic here (from a post above) about half way down the page: http://www.hq.nasa.gov/office/pao/History/computer s/Ch6-2.html [nasa.gov]

A 16 bit computer with 128 registers and an 8k memory. Pretty good as in 1977 I was playing Star Trek (simple grid system)on an IBM at uni with 8k. The Voyager was cutting edge at the time.

Its probably the different pots of money question. (2, Insightful)

Thanster (669304) | more than 6 years ago | (#20439291)

In (my experience of) public finances, an expenditure to re implement a protocol would be a capital expense, bring on "careful" scrutiny of the whole programme, and risk all these scientists jobs etc. (with no guarantee of getting the cash) and given that the question being answered is more than an entire career in the making (wall clock wise)......... A maintaince bill for existing equipment gets paid (almost) no questions asked.......

it's cheaper, this way. (1, Insightful)

Anonymous Coward | more than 6 years ago | (#20439337)

reanalyze and redesign the whole system, even with the goal of emulating it on current hardware, would cost a fortune.

i think it's safer and cheaper to leave it alive...

for younger folks thinking about emulating it on an off the shelf machine: current architectures and hardware are not always "better"; space exploration aside, for certain goals it's simpler to use a '70 thing working a custom tailored board than a oh-shi...-look-at-that-latency-its-impredictable!- harware...

6502s and z80s are still manifactured, indeed.

Re:it's cheaper, this way. (1)

Detritus (11846) | more than 6 years ago | (#20439571)

You make a very good point. Old systems had deterministic timing. No cache, no virtual memory, no bloated-pig operating systems designed by idiots in Redmond. You could actually make statements like "there is a 13 microsecond delay between receipt of command X and the initiation of pyro Y".

Re:it's cheaper, this way. (3, Interesting)

MichaelSmith (789609) | more than 6 years ago | (#20439727)

Old systems had deterministic timing. No cache, no virtual memory, no bloated-pig operating systems designed by idiots in Redmond.

A typical mainframe of 30 years ago would have done a lot of batch processing. But it still multi tasked. Only an embedded system would have had deterministic timing. And that is true of today as well.

I funded a hitch hiking holiday in Tasmania in 1986 by doing small withdrawals in the middle of the night when ATM's couldn't connect to the banking systems because overnight jobs were running.

Re:it's cheaper, this way. (1)

Alioth (221270) | more than 6 years ago | (#20439805)

6502s still manufactured? I thought CSG went bust years ago. Who makes them now, where can you buy one?

I know the Z80 is still manufactured; I have a 40-pin DIL "classic" Z80 on my table datecoded late 2006, and many electronics wholesalers stock them.

Re:it's cheaper, this way. (1)

ajlitt (19055) | more than 6 years ago | (#20440013)

WDC holds the patent on the 6502 and still sells chips and cores.

The original equipment probabily just works... (5, Insightful)

Anonymous Coward | more than 6 years ago | (#20439349)

Communication with different equipment has been done. http://www.arrl.org/news/stories/2006/04/25/2/ [arrl.org]

Proof that it's not a problem to receive and decode. Transmit can't be any harder. But why "upgrade" it if they don't have to? The old equipment probably works just fine, so there is no incentive.

Relivs of a time... (2, Interesting)

Swampash (1131503) | more than 6 years ago | (#20439489)

...when NASA inspired me, and the projects in which it was engaged filled me with wonder and curiosity. Nowadays the only thing that amazes me about NASA is the bureaucracy. Well, and the big explosions of course.

Re:Relivs of a time... (1)

Anonymous Coward | more than 6 years ago | (#20439559)

Right, because there is no wonder in 2 man made objects being where none have been before. Not to mention surviving much longer than was expected.

The reason for all that legacy equipment... (5, Funny)

itsdapead (734413) | more than 6 years ago | (#20439513)

(ring) (ring) (click) G'day, this is Tidbinbilla, how can we help?

"Er, Hi, This is Ranesh from Advanced Emulation Solutions... I'm testing the VM you commissioned to replace your legacy communications solution. Thing is, there seems to be an undocumented bug in the command protocol and the remote client has locked up. Could some one pop over and power-cycle the client, please?

****???^^^^!!!!

Hey - take it easy - "no worries" as you guys say - just turn off the power, count to ten and turn it on again!

$$$$!!!!##### !!!!!

Er, 15.5 billion kilometers, you say? Look, I know you guys like to boast about the size of Australia, but...

$$$$ ****ING OUTER SPACE !!!!! MOST DISTANT MAN-MADE ****ING OBJECT !!!!!

Oh. Shit. I wonderered why the ping time was 24 hours.

Don't you guys have on-site support?

Re:The reason for all that legacy equipment... (2, Funny)

Bob of Dole (453013) | more than 6 years ago | (#20439701)

I was gonna do the standard slashdot geekjerk thing and point out what the actual ping would be, but
12.5 billion kilometers / speed of light is 11.58 hours.
So 24 hours is just about right! Well done sir.

(although it's closer to 23 hours...)

Re:The reason for all that legacy equipment... (4, Funny)

MichaelSmith (789609) | more than 6 years ago | (#20439759)

although it's closer to 23 hours

Takes an hour for the processor on Voyager to unpack an ICMP message, parse the ping, compose a reply, encapsulate and send it.

Re:The reason for all that legacy equipment... (1)

Ron Bennett (14590) | more than 6 years ago | (#20439887)

So at their current rate of travel, in about 30 years, get prepared to celebrate when the first of the probes will finally reach the distance of 1 lightDAY!

This contradicts wikipedia (1, Informative)

Anonymous Coward | more than 6 years ago | (#20439519)

Wikipedia says that it was possible for amateur radio operators to receive data:

On March 31, 2006, the amateur radio operators from AMSAT Germany tracked and received data from Voyager 1 using the 20 m dish at Bochum with a long integration technique. Its data was checked and verified against data from the Deep Space Network station at Madrid, Spain. AMSAT-DL article in German [amsat-dl.org] ; ARRL article in English [arrl.org] . This is believed to be the first such tracking of Voyager.

Where can I get some of these computers? (1)

BlackMesaLabs (893043) | more than 6 years ago | (#20439527)

There was a really awesome picture (in the newspaper here in Sydney) of the scientist in front of the computer equipment they were using. The stuff looked like your stereotypical retro computer control panels/racks, complete with illuminated, colourful buttons, blinking lights, and so on. It looks like the control room for an old missile silo, or, (would you believe it) old-school space command!
Where can I get some dummy/discarded panels? I want to replace all the walls in my room with them, and wire up some LED's to blink randomly/illuminate when I press the buttons.

Where are the photos? (1)

trawg (308495) | more than 6 years ago | (#20439545)

How'd they manage to write an article saying the computers "would look at home in black-and-white episodes of Doctor Who" without managing to include a photo of said computers :(

You FAIL It!? (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#20439569)

to 3ecline for

I worked on this project (5, Interesting)

rimcrazy (146022) | more than 6 years ago | (#20439651)

What is little known externally except by those that actually worked on this project is that the radios work at all is amazing. Motorola GEG built the radios in the Voyager spacecraft. Right after launch of both space crafts there was a failure of a critical capacitor that sets the bandwidth of the acquisition loop filter. The net result of that failure was that the signal acquisition of the radios was severely impaired. In order to compensate for this NASA engineers developed an emperical model of the entire spacecraft while it was on it's initial loop around the sun for it's slingshot to Jupiter. Since it was relatively close they could hit the spacecraft with a very large signal thus ensuring acquisition of the transmitted commands. The model consisted of predicting exactly where the front end input LO would be depending upon the temperature of the space craft, the added doppler due to movement, aging of the crystals, etc, etc. Basically anything that could effect the LO was factored in. Once the model was complete, the ground stations would then use and probably still use, this model to predict what the frequency for lockup needs to be. Due to the efforts of the engineers at NASA, they were able to "save" both spacecraft and the mission. And they still work today!!! Pretty amazing.

outmoded? (2, Insightful)

timmarhy (659436) | more than 6 years ago | (#20439669)

Sounded a lot like penis envy to me. Those engineers in the 70's knew what they were doing, unlike the kids today who breeze past their competency based exams.

The voyager sats are some of our most successful missions, i'd challenge anyone to do better then their "out modded" systems.

Re:outmoded? (2, Funny)

Rosco P. Coltrane (209368) | more than 6 years ago | (#20439835)

The voyager sats are some of our most successful missions, i'd challenge anyone to do better then their "out modded" systems.

The IRS seems to be pretty succesful: they still run their 1960s mainframes [com.com] , yet they're still pinching everybody's money. That's one mission everybody would like to see fail...

What's the problem with modern comms hardware? (1)

Jugalator (259273) | more than 6 years ago | (#20439801)

I don't really understand the part about having to preserve ancient hardware from the 70's to communicate with them.

Isn't it just based on pretty simple technology, and a quite simple communications protocol?

How complex can a software to communicate with the Voyager probes be, and can't it be ported?

Sure, the hw it runs on over at NASA won't be the same, but the end requirement simply has to be to communicate with radio waves over high latencies, and they have plenty of modern hardware for that, or...?

Photos (1)

Alioth (221270) | more than 6 years ago | (#20439817)

Anyone got any good pictures of these "old computer banks"? If so, URL?

Old but built to last (1)

edwardpickman (965122) | more than 6 years ago | (#20439877)

It's the computer equalant of tin cans and string. The string may be frayed but if you cut it you may never get it working again. It does make you wonder how much luck alien civilizations will have decrypting our signals if we have this much trouble communicating with our own technology? Can they possibly do it? Of coarse but how much effort will it take and are the shaved chimpanzes beaming I Love Lucky at them really worth their time and trouble to talk to? Or will our first communication with aliens be, "please resend episode 23, signal got garbled by solar flare."

As a note aside on the article (0)

Anonymous Coward | more than 6 years ago | (#20440073)

Voyager carries disks containing images, languages, scripts and sounds of Earth, cut into a groove of a disk made to last. Those images have been put together from the finest exhibits of art, music, photography and other areas that the team responsible for the disks could muster.

As a consequence, the material is mostly copyrighted, not in the public domain. There has been a limited amount of books and CDs with the contents sold on Earth, but it has long since gone out of print, and copying it is, of course, not permitted. When this changes in centuries to come, the CDs will no longer be readable.

So for us humans, this unique collection of the finest pieces of what makes life and culture on our planet unique in space, is bent to be lost. It is already no longer available to the public.

Maybe at least some bug-eyed aliens will at one point of time be able to enjoy them. But looking at how our own historians keep things like the Qumran scrolls, finds of a distant culture, under wrap and control, we should not hang our hopes too high.

"Why can't they just" (3, Insightful)

DynaSoar (714234) | more than 6 years ago | (#20440121)

When someone says "Why don't they just", it usually means they have no idea how it's being done, and is just taking that opportunity to show what they know, even though they have no idea if it's applicable.

When someone says "Why don't we just", they're probably working on the project and know what they're talking about.

If they could just, they probably would have justed a long time ago. These are, after all, the people who rebuilt the receiver scheduled to receive the Apollo 11 LEM and EVA transmissions in just 12 hours, after it caught fire 1 day into the mission. It was NASA's call not to use them due to the problem, but they could have done it because they know very well what they're doing and how to do it.

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