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Where are the Voyagers?

voyager.jpl.nasa.gov

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Re: Where are the Voyagers?

#41

Post by hcrisp »

civilian wrote: post #3
josho wrote: post #2

As amazing as space technologies are, we are in the stone ages when it comes to spaceflight: > Earth moves around the sun faster than Voyager 2 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year. We don't even have the technology to escape the sun's gravity without needing a gravitational slingshot from other planets, and that still leaves us with a…

Nitpicky but.... we'd still want to use gravitational slingshots even if we had more deltaVs to burn.

Yes, in fact per Mark Adler [0] you'd use a Jupiter flyby to fly back to the sun and then do a high thrust burn at closest approach to maximize your speed into interstellar space (Oberth effect).

[0] https://www.quora.com/Can-we-use-the-gravity-of-the-sun-to-s...

Re: Where are the Voyagers?

#42

Post by patrickmn »

sidcool wrote: post #36

> Because Earth moves around the sun faster than Voyager 1 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year. So obvious yet so mind blowing.

We really are on a fragile blue ball doing loop-de-loops through space!

Re: Where are the Voyagers?

#44

Post by RangerScience »

patrickmn wrote: post #42
sidcool wrote: post #36

> Because Earth moves around the sun faster than Voyager 1 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year. So obvious yet so mind blowing.

We really are on a fragile blue ball doing loop-de-loops through space!

Wiggly loop-de-loops.

Re: Where are the Voyagers?

#45

Post by zipwitch »

pavel_lishin wrote: post #17
Normal_gaussian wrote: post #9

Earlier quoted context omitted.

It would be nice, and is certainly the result I hope for (with all the good wishes do), as I'm not sure we will work very well with slow and expensive growth. Reading 'Against a Dark Background' was certainly interesting as it considers a system which essentially has its growth capped by the distance between itself and the rest of the universe.

Something I noticed in that novel is that they still had incredibly advanced technology. The Lazy Guns alone hint at what they lost! Maybe there's a reason Golter is where it is, and maybe it wasn't always there.

I read _Against A Dark Background_ as a teen an thought of it as a pretty fun sf, almost space-opera adventure story. Then I read it again as an adult and... wow. Bank's SF work is very good, but the quiet existential horror that lurks behind the scenes in that novel really merits the title. Makes good old Lovecraft seem like a piker by comparison.

Re: Where are the Voyagers?

#46

Post by jcranmer »

ant6n wrote: post #13
rm_-rf_slash wrote: post #6

Earlier quoted context omitted.

Problem is we don't really know where to go next. Jeff Bezos' Blue Origin tried to cook up alternate space travel methods for years and still couldn't come up with anything better than the same basic rocket model that put Gagarin into space. Most theorized "warp drives" either require more energy than humanity is capable of producing or necessitate breaking a law of physics or two just to move anything organic or lar…

There's the EM drive, maybe. Some recent discussion: https://news.ycombinator.com/item?id=12995125 If you can create trust out of electricty (ion drives also come to mind), then if you have nuclear power or fusion, things get interesting again in terms of propulsion. To reach orbit, there are a bunch of interesting proposals: skyhooks (i.e. space elevator light), launch loops, railguns.

The EM drive is reported as producing maybe 1 mN per kW. The largest power plant in the world produces about 22 GW of energy--at that ratio, an EM drive could produce maybe 22 kN. The first stage of the Saturn V rockets produced 35,000 kN of thrust.

As a practical engine, EM drives are worse than chemical rockets or even ion thrusters (which produce about 25-250 mN/kW, according to Wikipedia).

Re: Where are the Voyagers?

#47

Post by lisper »

patrickmn wrote: post #42
sidcool wrote: post #36

> Because Earth moves around the sun faster than Voyager 1 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year. So obvious yet so mind blowing.

We really are on a fragile blue ball doing loop-de-loops through space!

If you shrunk the sun down to the size of a ping-pong ball, earth would be a poppy seed orbiting ten meters away. Pluto would be 100m away. The Voyagers would be 300m away.

The nearest star, Proxima Centauri, would be 500 miles away.

Re: Where are the Voyagers?

#48

Post by Normal_gaussian »

ars wrote: post #19
Normal_gaussian wrote: post #7

Would be really cool to stick some velocity numbers on there as well, I find it hard to relate to such huge distances. 62 thousand kilometres per hour feels larger because I can kind of comprehend it. Though really cool anyway, I was going to say that Voyager 1 managed short of 30 light seconds a year until I realised the question is one of acceleration and deceleration not velocity. If I wasn't on my way to bed I wo…

> Would be really cool to stick some velocity numbers on there as well Bottom of this page: http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm

That is a great resource, thank you

Re: Where are the Voyagers?

#50

Post by angusp »

josho wrote: post #2

As amazing as space technologies are, we are in the stone ages when it comes to spaceflight: > Earth moves around the sun faster than Voyager 2 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year. We don't even have the technology to escape the sun's gravity without needing a gravitational slingshot from other planets, and that still leaves us with a…

Not really, earth is waaaay closer to the sun, so goes faster in its orbit but has a lot less energy (when normalised for mass) than any of the voyagers. They are going way faster than Earth in the sense that we're they to suddenly to telephone to Earth's perihelion, they'd be going ridiculously fast relative to Earth
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