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Voyager 2 is back online after eight months of radio silence

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Re: Voyager 2 is back online after eight months of radio silence

#31

Post by Retric »

metiscus wrote: post #13
Cthulhu_ wrote: post #11

Earlier quoted context omitted.

Interstellar travel, unless there's a revolution in propulsion, is unlikely to happen I think. I'm sure that at some point they'll send up another probe with more fuel to go out faster, but it's not going to be revolutionary.

The tech has existed at least theoretically since the 60s but nobody is willing to use it. https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...

Project Orion is kind of ludicrously inefficient, making it largely useless for interstellar travel. A nuclear powered ION engine can achieve a much higher exhaust velocity and replace that giant pusher plate with useful propellant.

It’s one of those designs that trades something considered largely meaningless, total engine weight, for something considered far more important exhaust velocity. This always ends up being a far worse trade off than simple models suggest.

PS: It could have very high acceleration before running out of fuel, but if the trip is going to take decades either way that’s not very important.

Re: Voyager 2 is back online after eight months of radio silence

#32

Post by pvaldes »

Lets imagine... hypothetically [1] that we could design a new kind of space oriented machines, sort of a "spatial server" or a "telephone repeater", that could be left in Pluto (or an asteroid, or orbiting Saturn, whatever...), and be designed to take this weak signals, amplify it, and resend it to the earth

Would this help to increase the range of what discover can report and... hum, discover?

Would help us to have the info in two months instead in eight? (maybe splitting in a multipart message and broadcasting in several threads and different frequency bands at the same time or so?).

or would be basically useless?

Could be used to start a exploring outer web that would be improved with each new launching as other countries connect to it?

[1] I don't know how realistic, or technically difficult would be. Is an idea idea that just occurred to me

Re: Voyager 2 is back online after eight months of radio silence

#33

Post by elcomet »

dirktheman wrote: post #23
ponker wrote: post #22

Earlier quoted context omitted.

They didn't even spin something 350 times before launching it out of the solar system?

If the actuator broke down the 351st time, would you've commented 'they didn't even spin something 400 times...'? What would be a number you'd be comfortable with instead?

Maybe the expected number of times it would be expected to spin in space (or twice that to make sure it's working)

Re: Voyager 2 is back online after eight months of radio silence

#34

Post by amelius »

elcomet wrote: post #33
dirktheman wrote: post #23

Earlier quoted context omitted.

If the actuator broke down the 351st time, would you've commented 'they didn't even spin something 400 times...'? What would be a number you'd be comfortable with instead?

Maybe the expected number of times it would be expected to spin in space (or twice that to make sure it's working)

The initial Voyager program already ended, and they are now in an "extended" mission.

Re: Voyager 2 is back online after eight months of radio silence

#35

Post by jacobush »

mkl wrote: post #25
prox wrote: post #18

Earlier quoted context omitted.

Future Crew - Second Reality

That was a 1993 PC demo, not C64. I had to mess with my config.sys and autoexec.bat to get it to run, but watched it repeatedly.

Yeah but that demo was later re-created on the C64, arguably the C64 version is better. :-D

Re: Voyager 2 is back online after eight months of radio silence

#36

Post by rmu09 »

ponker wrote: post #22
superasn wrote: post #3

I was just reading the pale blue dot and he mentions that Voyager 2’s scan platform jammed after its encounter with Saturn. Voyager 2 emerged from behind Saturn (as seen from the Earth) in August 1981. The scan platform had been moving feverishly—pointing here and there among the rings, moons, and the planet itself during the all-too-brief moments of close approach. Suddenly, the platform jammed. A stuck scan platfor…

They didn't even spin something 350 times before launching it out of the solar system?

Accelerated simulation of the effects of years in the vacuum and temperature of outer space on lubricants is non-trivial.

Re: Voyager 2 is back online after eight months of radio silence

#37

Post by m4rtink »

jacobwilliamroy wrote: post #21
m4rtink wrote: post #17

Earlier quoted context omitted.

Well, you don't necessarily need to launch from Earth - starting an Orion mission from say high lunar orbit should be perfectly safe.

Maybe. Personally, I would want to see A LOT of math and paperwork first before I listen to anyone who uses "perfectly safe" and "nuclear explosion" in the same sentence. I'm still hoping we can figure out some other form of space travel which doesn't involve really, really, really big explosions.

Nuclear Salt Water Rocket rides on one smaller continual nuclear explosion: https://en.m.wikipedia.org/wiki/Nuclear_salt-water_rocket

Re: Voyager 2 is back online after eight months of radio silence

#38

Post by roter »

pvaldes wrote: post #32

Lets imagine... hypothetically [1] that we could design a new kind of space oriented machines, sort of a "spatial server" or a "telephone repeater", that could be left in Pluto (or an asteroid, or orbiting Saturn, whatever...), and be designed to take this weak signals, amplify it, and resend it to the earth Would this help to increase the range of what discover can report and... hum, discover? Would help us to have…

I like it. You'd need (many) more than one. Pluto has an orbit of 248 years. Kind of like putting your wifi router on a train track on your property line and sharing with your neighbours.

Perhaps on a bunch of objects at Lagrange points [0]?

[0] https://en.wikipedia.org/wiki/List_of_objects_at_Lagrange_po...

Re: Voyager 2 is back online after eight months of radio silence

#39

Post by marcosdumay »

Retric wrote: post #31
metiscus wrote: post #13

Earlier quoted context omitted.

The tech has existed at least theoretically since the 60s but nobody is willing to use it. https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...

Project Orion is kind of ludicrously inefficient, making it largely useless for interstellar travel. A nuclear powered ION engine can achieve a much higher exhaust velocity and replace that giant pusher plate with useful propellant. It’s one of those designs that trades something considered largely meaningless, total engine weight, for something considered far more important exhaust velocity. This always ends up bein…

What good does a high exhaust velocity if your fuel stays all inside the ship?

Re: Voyager 2 is back online after eight months of radio silence

#40

Post by frank2 »

rmu09 wrote: post #36
ponker wrote: post #22

Earlier quoted context omitted.

They didn't even spin something 350 times before launching it out of the solar system?

Accelerated simulation of the effects of years in the vacuum and temperature of outer space on lubricants is non-trivial.

But a duplicate of the actuator failed in a lab on Earth after almost exactly as many turns as the actuator in space lasted -- that's how they determined the cause of the spacecraft's going offline.
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