23
$\begingroup$

According to the NASA Website, the Voyager probes will begin powering down electrical components soon with all electronic functions ceasing some time around 2025.

With no ability to transmit back to earth and thus of 0 value in the Interstellar Medium...

...could either one (or both) of the Voyagers be directed back to Earth at all before electronic shut down?

If not; do aerospace engineers have any idea where either (or both) of the probes may end up?

$\endgroup$
10
  • 24
    $\begingroup$ "What if?" covered what it would take to retrieve Voyager 1. $\endgroup$
    – Schwern
    Feb 23, 2017 at 5:46
  • 3
    $\begingroup$ Yes, and it is going to happen about the year 2273 (near Stardate 7500) as predicted in the movie! $\endgroup$ Feb 23, 2017 at 19:28
  • 2
    $\begingroup$ "0 value in the interstellar medium" Not true; they are incredibly useful in announcing our presence to any other species that might happen across them. $\endgroup$
    – TylerH
    Feb 23, 2017 at 19:36
  • 3
    $\begingroup$ Since Voyager is 40,000 years away from coming close to another star...we can say 'slightly' above zero ;-) $\endgroup$ Feb 23, 2017 at 20:21
  • 1
    $\begingroup$ Hopefully, in the future it will be a piece of cake to retrieve them because we will have fractional light speed drives or wormhole technology or displacement engines. $\endgroup$ Feb 23, 2017 at 21:21

3 Answers 3

61
$\begingroup$

No, not even slightly. Neither Voyager has much fuel left; in fact, they don't have much fuel even for changing their attitude (the way they point), which is orders of magnitude less fuel than for making major course changes, and the course change necessary to return to Earth is so large it would never have been possible in any case: both probes used gravity assists for the majority of their velocity gain in order to get where they are. The probes would have to have been at least hundreds of times larger than they are to have any chance of returning, meaning we would have to have launched far more into space at one time than has ever been done.

We do know where they're going, though: nowhere in particular. Space is a very very big place.

However, if and when they ever get anywhere with intelligent life, they do have one last possible mission. Both probes have diagrams, long-lasting records, and record playing styluses designed to give possible aliens some idea of what we look like, where the probe came from, and what Earth sounds like. It's very unlikely that this will ever be relevant, but it was considered useful enough to justify the extra few hundred grams. (Also, it gave some fodder to e.g. Star Trek.)

$\endgroup$
10
  • 14
    $\begingroup$ If you care about just how hard getting them back would be, XKCD has a 'what if' about salvaging voyager 1. Short answer, about 12 saturn V's of fuel. what-if.xkcd.com/38 $\endgroup$
    – Leliel
    Feb 23, 2017 at 3:52
  • $\begingroup$ Could you expand on the fodder to Star Trek? $\endgroup$
    – nindalf
    Feb 23, 2017 at 10:10
  • 7
    $\begingroup$ @nindalf V'ger from Star Trek Motion Picture $\endgroup$
    – PTwr
    Feb 23, 2017 at 11:15
  • 1
    $\begingroup$ Basically, the only way would be if there's another large planet out past pluto that they could use to slow down and they're already heading for it in almost exactly the right way, which is quite highly unlikely. $\endgroup$
    – Perkins
    Feb 23, 2017 at 19:33
  • 1
    $\begingroup$ @Perkins - The first is actually not that unlikely, although the second is exceedingly so. $\endgroup$
    – Bobson
    Feb 23, 2017 at 23:37
9
$\begingroup$

Nope. They have small amounts of hydrazine fuel left and have no possible way to slow down and head back. They are traveling very fast (Voyager 1 is at 38,088 mph or 17.027 km/s relative to the sun) and have very little ability to change speed now. The hydrazine is used for attitude control and will outlast their RTG, but it could only change the velocity in a small way.

$\endgroup$
8
$\begingroup$

Return to earth with the remaining fuel is totally impossible. Voyager was started from earth with a very large and heavy rocket tanked with a lot of fuel. Returning to earth would require a rocket of the same or even larger size, but this rocket should be there were Voyager is now. But it is impossible to transport such a gigantic payload like this rocket from earth to the location of voyager. We are not able to build and finance such an incredible large rocket needed for a such a mission with a return ticket. The rocket needed for return should work without problems decades after start from earth. We are not able to build such a complex system that should work almost a century.

$\endgroup$
2
  • 4
    $\begingroup$ +1 but the rocket should be even bigger because Voyagers used gravity assists to get where they are and we don't have gravity assists to stop them. $\endgroup$
    – Pere
    Feb 23, 2017 at 9:34
  • 1
    $\begingroup$ @Pere: On the flip side, if one of the Voyager craft happens to fly near some objects that have just the right combination of size, position, and velocity, such objects could provide gravity assists that would return the craft to Earth without any additional fuel expenditure. Of course, the reason big planets worked for gravitational assists is that the crafts' paths were deliberately chosen for that purpose. The probability that other bodies would--purely by coincidence--provide the necessary gravity assists for a return to Earth is indistinguishable from zero. $\endgroup$
    – supercat
    Feb 23, 2017 at 22:45

Not the answer you're looking for? Browse other questions tagged or ask your own question.