NASA tells Voyager 2 to save its strength Voyager 2 is conserving energy by using its back-up thrusters as it continues to boldly go where no spaceship has gone before. The second of NASA's explorers of the space beyond our solar system has accepted commands from the space agency's Deep Space Network personnel to switch to the back-up thrusters that control the roll …
I still think that any manned space flight is very impressive. I think even you would be impressed if you were strapped to the top of rocket with the fuse lit and the sky beckoning!
Terry Pratchett in one of his book pointed out just how weird we are. Boredom - we're the only species to have it so bad that walking on the moon became not worth the TV air time after just two landings.
NASA have been stunningly successful in their unmanned program. Pretty much all of their deep space probes have sent back amazing results. And in the case of Voyager, it still is.
Not always, they've had some superb failures too... Like mixing up the units for the mars probe, and smashing it into the surface, or did it miss the planet entirely? Can't remember which.
I really have no idea what kind of crazy fool would even think of doing scientific calculations with imperial units, but it appears NASA do/did.
So .. what are we ceeding on our decendants?
- A super trancendentally evolving probe that returns to us in a few centuries to find us still punting bits of junk into low orbit, at which point it scans us and disappears into some higher dimensional state?
- A bit of interstellar garbage for some space alien to take a pot-shot at
- A lure that will bring untold woe when brain-sucking aliens follow its helpful "come see us soon" information plaque.
It's about a 26 hour round trip, just about bearable for unambiguous commands with a reasonable confidence of correct response. Would have thought it would be longer than that, in fairness. Not too bad a routine for the techs: come into the office, send a message, pick up the reply a little later the next day.
.. to send a message to it (at the speed of light), and a further 13 hours to receive it's reply - one whole Earth day and a couple of hours on top to await each response. That's one hell of a round trip time. The latency on the console must be awful...
Nasa's web page on this project show it travelling at over 56,000 kph (35,000 mph). You won't get that kind of speed on the M25 during a busy afternoon, I can tell you...
When these voyagers were sent on their way in 1977 the 14k4 modem hadn't been born. Even a 300 baud modem was rocket science (hmm, pun intended I think...) back in those days. But what I'm surprised about is that they found room for an old GPO telephone handset so that they could attach the suckers.
Sorry, I'm getting old. Way to go Voyagers!
Paris, because I mentioned suckers and I think I'd be happy if she were a sucker.
C:\>ping voyager2.nasa.gov -w 100000000
Pinging voyager2.nasa.gov [193.170.140.78] with 32 bytes of data:
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Well I pinged that address and got nothing...So I guess it has just turned off the reply to save even more power...aha....WTF It's coming back at us....Turn your iphones off nowwwwwww
Pinging voyager2.nasa.gov [193.170.140.78] with 32 bytes of data:
Reply from 193.170.140.78: bytes=32 time=1005400000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=1005400000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=1005400000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=93600000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=84500000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=49200000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=25900000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=10200000ms TTL=56
Reply from 193.170.140.78: bytes=32 time=3600000ms TTL=56
In relation to the challenge of controlling a space probe at such great distances; I believe it would actually be possible (not necessarily practical) to use a series of on board 'delayed choice' experiments to issue instantaneous binary commands to a remote space probe, effectively bypassing the traditional dimensional limitations of space & time.
Discuss...
NASA should be making cars, computers and toasters. If only those worked flawlessly for 10 years, nevermind 34 years!
By my calculation a command takes 13 hours to travel from Earth to Voyager's current location. So NASA have to wait at least 26 hours after transmission to see if Voyager received it!
12w is only the reduction on total power (The power plant is fading over time) reducing the load will enable it too keep running without browning out. As the power plant and supply fades you have to keep turning the power drain down by turning things off..
Voyage was able to produce 470W at launch now it is down to just 270W
(See: http://www.jpl.nasa.gov/news/news.cfm?release=2011-341&rn=news.xml&rst=3189)
Note that the 200 watts lost over 34 years is on a diminishing scale, not linear (meaning less is lost each year) so this 12w saving will last longer than it may appear.
It's the nuclear thermal generator that keeps the probe "warm".
Aaaah, when NASA could builld hardware and software that actually works.... and thought about the future, not when Apollo was the past, not the future... now they only think how they could put together another Apollo just with some new LCD panels to make it look "futuristic" - just their scratching their heads to understand how those engineers in the sixties without iPhones and iPads have been able to put Apollo and Saturn together and make it work... probably because of the lack of them. Much more time available to understand how to make hardware work.
Voyage has 2 sets of control thrusters, they are turning off the primary system to save power, but there will be no backup if the operating one fails.
They roll the ship to perform experiments, then point the dish back towards earth to transmit the results.
Also to compensate for changes in attitude due to external factors, e.g. being hit by micrometeors.
There isn't enough sunlight out there, our sun looks like a star. So it uses radiothermal generators. The fuel is plutonium, and as it decays, over the years, the power output drops. So now they have nowhere the power they started with.
The biggest risk with RTGs seem to be people stealing the outer casings for scrap value, luckily the Voyagers have adequate theft protection.
There's not enough sunlight at that distance to keep anything warm. The Voyagers are powered with RTGs (Radioisotope Thermoelectric Generators). They produced about 470 Watts of power at launch, but, due to the decay of the radioisotopes (radioactive Plutonium), the power output has decreased over the years. The decreased power output from the RTGs is what is causing the need to conserve power.
Dave
or the mission would have failed before it passed Mars.
Jimmy Carter was US president in the year of the launch in 1977, Pierre Elliot Trudeau was prime minister of Canada and James Callaghan, was UK prime minister. Clive Sinclair introduced his new two-inch screen television set, which retails at £175, and The Archers had been running 25 years.
This probe demonstrates that America did have the technical skills at one time. What happened since then?
You could refer to the probe as "MJS-U 77", its design name. Voyager 1 was called "MJS-T 77".
I remember when it got a little dicey soon (one year?) after launch when the receiver on board got its frequency control all out of whack. They needed a modification to the deep space network to recover (adjust the transmitter instead of the broken receiver).
Remember, there is a "postcard" and a record attached to both Voyager probes. Chuck Berry lives in space (Johnny B. Goode).
@Jaitch
"...This probe demonstrates that America did have the technical skills at one time. What happened since then?..."
...that the technical skills in the US space missions came from captured and immigrant German technologists.
What happened was that the Germans got older, retired and died. And no other Germans came over to take their place.
OK so I understand the atomic generator thingie but I would be fascinated to hear about the thruster fuel.. like how much did it take with it, how much is left and what's the MPG on that then!
Fantastic achievement, i doubt the original designers ever got the rewards they deserved, other than an immense sense of pride of course.
Hydrazine.
Basically as you are in space there is very little resistance so your fuel consumption is determined by the number of manoeuvres you need to make and how quickly you want those manoeuvres to occur.
So if you can wait 2 weeks for the thing to turn around and only do it once every 3 months then very little.
I'm not joking! It's a voice message, I'll clean it up a little... patching it through now...
"John Madden John Madden John Madden John Madden John Madden"
"aeiou aeiou aeiou aeiou aeiou aeiou aeiou aeiou"
"Question mark exclamation point question mark exclamation point question mark exclamation point"
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