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Voyager Probes Give Us ET's View
astroengine writes "For the first time, scientists have been able to measure a type of radiation streaming out from the Milky Way that in other galaxies has been linked to the birthplaces of young, hot stars. There was no way to make our own galaxy's measurement of the radiation, known as Lyman-alpha, until the Voyager probes were about 40 times as far away from the sun as Earth — any closer and the solar system's own emissions drowned out the fainter glow from the galaxy."
The Voyager computers are awesome too. How many other 18-bit word systems are actively maintained today?
I'd love to see the source code, though I'm sure it's terribly boring.
The distance at which the Voyagers are still collecting and transmitting useful data back to Earth, is mind boggling.
Over a light day away!
Back in 1989, when Voyager 2 flew past Neptune, the JPL command center was probably dismantled and refitted for the next glamor project, while the long final phase of the Voyager mission was relocated to a much tinier space, probably the basement, with a couple of old-school, hardcore Voyager geeks down there, living on Doritos, pizza and Usenet, a rickety AC rattling and slowly dripping water over a puddle, unfixed for months because the Maintenance Department is constantly needed up at Voyager's old stomping ground, kept immaculate for the Galileo probe people, or Cassini, or the Mars Rovers, whatever the Flavor Of The Lustrum was / is.
Nice and quiet down there among the rusted ceiling pipes and aged Crays, though. They didn't bother nobody, nobody bothered them. Beer could be smuggled to work and no one would notice, everybody upstairs would be swooning over Neil DeGrasse Tyson filming a segment on Pluto and the Horizons mission. Only time anybody saw the strange Voyager geeks, was when they went up to the ground floor vending machines, as the supply guy always forgot to restock the one in the JPL basement, forgot there was one in the basement.
Little did anybody know (except for these guys) that the Voyagers were like an aging boxer with one good fight left in them, very low bitrate coupled with an ultra-weak signal perhaps, but with still one final, grand potential payoff - a peek at the outside, which may end up being the longest lasting legacy of all.
Look at it now bitches, it's on the other side of the heliopause!
Lil' Thindime, lilting a lacrimose lament, krashes the kwaint konfines of Kokonino Kounty
Oh, I don't know... electrostatic ion propulsion is already proven to be more efficient than ordinary chemical propulsion (once you get out of the gravity well).
As long as you have fuel, you'll keep accelerating, albeit at a very small rate. It might take ten or twenty years, but I reckon that if an ESI probe was launched tomorrow it'd overtake Voyager and still have propellant to go faster.
The bonus is with computer technology; that while it's gotten thousands of times faster in practically every respect, it's also gotten a lot smaller - a non-hardened computer package these days weighs no more than 3lb, with terrestrial ruggedised coming in at little more. The advantage of this is obvious: with the single biggest non-fuel component of the spacecraft now the size of a paperback, you have far less mass to push.
Of course, you don't need a screen or a keyboard in deep space, so cut the weight in half and you've got something a smidge lighter than the several hundred pounds of GE custom machine that went up with Voyager, that has its own battery, that pulls about ten Watts rather than over a hundred, that uses solid state storage, and in most cases can automagically govern its own power load (this would be why the later Shuttle missions used self-contained laptops rather than a room full of mathematicians and radio that meant data moved at the speed of speech) - I've metered my netbook off the line and found it runs on between 3-35W, averaging 11, including the screen on minimum brightness.
That said, you do need to protect the computer against hard radiation. That will obviously push the weight up, but not so much as to make it unmanageable. A couple or three pounds of lead and a steel cage to protect against EMI/RFI I think is all that is needed. The major part of the probe is then going to be propulsion systems and fuel, and the science package.
Operation Guillotine is in effect.
They wouldn't be using state of the art chips, but even the old radiation hardened chips needed for space travel would be an big improvement over 30 year old technology.
Probably the biggest improvement would be in propulsion. Isn't this the exact sort of mission the new ion propulsion systems would be perfect for?
We hope your rules and wisdom choke you / Now we are one in everlasting peace
It's an interesting question, but regardless of whether anyone can theoretically crack the authorisation to upload commands to the Voyagers, I believe that it's only NASA's deep space network that can actually send the signals that far to be received by the probes.
Not that anyone is probably interested but I worked in the group that made the radios that are in Voyager. I just missed working on those specific models but I worked on the next generation following those use on Voyager. Working there (Motorola GED) I worked close with NASA and was in the loop on all the programs, past and current that we were working on with NASA. What is really remarkable here is both Voyager probes have "failed" receivers on them. There was a problem with the capacitors that were used for the input loop bandwidth filters. These failed in such a manner as to cause the acquisition loop bandwidth to be a very narrow band instead of the intended wide band. NASA was able to recover using these radios by basically making an empirical model of each of the spacecraft. They did this when the spacecraft were relatively close to the earth and they could blast them with wideband signals to ensure acquisition. What they did with the model was to identify exactly how the on board xtals in the radio aged or varied with power and temp and then threw in compensation for age and doppler. With all of this data then then had a model that told them on such and such a date, the correct xmit frequency to use to put the carrier in the middle of the narrow band filter is X. They would dial it in, send it out and everything still worked. Actually a very clever fix for what would have been a disaster.
"TV, a medium as it is neither rare nor well done." Ernie Kovacs