If you wanted to have a probe pass Voyager 1 in 10 years, you would need to launch it today and get it going 15.9 AU/year, which is blazing fast. Almost 5 times as fast as Voyager 1. New Horizon, if launched today, could almost do it (14.13 AU/year), but it's mission wasn't set up to leave it traveling as fast as Voyager 1. Although it's going out in the same direction and was launched faster, it will ultimately end up going slower.
If you give yourself 10 years to design the probe and something to get it going that fast, then the speed you actually need jumps up to 19.5 AU/year. The longer it takes you to design your fast rocket, the faster it has to go in order to catch Voyager 1 in the same amount of time.
Realistically, unless something exotic happens in space propulsion technology, we will never catch Voyager 1 within our lifetime. If we launched today at twice the speed of Voyager 1, then we could catch it in around 50 years, but that's not going to happen.
Catch up and surpass something we launched decades ago, travelling (according to Wikipedia, entry was last edited .. today) 3.595 AU per year [1].
The question you're asking is hard to answer: When do you want to catch up? If we send a new object to space today, which travels 5% faster, is that good enough? It won't pass Voyager 1 for a looooong time, but will eventually.
Is that what you're aiming for? Why? Or are you asking for a magical way to cross that distance (35 years of traveling) 'instantly'?
Considering c is 63,198 AU/yr, and Voyager 1's only about 123 AU away, there's still a lot of room left for future engineers in increasing the speed of our devices to very quickly surpass it. Will we achieve even a hundredth of c within the next 100 years? Depends.
Just wondering, is there any technology we've seen actually used today that could produce a hundredth of c within the next 100 years? Would this be something we could see with ion propulsion for example?
Not used, but planned. Nuclear propulsion. No real limit on speed, apart from C, although as you go farther/faster you need REALLY big ships to carry enough fuel. c.f. project Orion.
Voyager did pass Pioneer 10 (1972) in the late 1990s. The alignment mentioned by others made the difference. New Horizons, which is going to Pluto, had the fastest launch speed of any man made object.
Launch speed isn't the whole story though. You can accelerate to ludicrous speeds once you're in space. Compare the following to New Horizon's launch speed of 16 km/s:
Note that those are going towards the sun, not away from it, and so benefitting from the sun's gravity instead of having to fight it.
Accelerating to ludicrous speed on the way out of the solar system is much more difficult.
My understanding (though I'm no astrophysicist) is that gravity boost from a planet works because of the relative velocities between the planet and the sun, whereas trying to use the sun's gravity to boost your solar system escape velocity would fail since gravity would be fighting you on the way out just as much as it was helping you on the way in.
This is correct. Planetary gravitational slingshots work with respect to Sun-relative velocities. Trying to use the Sun to slingshot out of the solar system is like trying to use Earth's gravity to sling into Earth orbit. Being at the bottom of a gravity well cannot help you to leave it. It's like riding a bike down a hill; you can't then use the kinetic energy to roll up a bigger hill than you started from.
A gravity assist works by robbing orbital momentum from the planet, transferring it to the spacecraft. (I once saw a calculation that Voyager's slingshot slowed Jupiter's motion by one foot per trillion years.) Jupiter has orbital momentum around the Sun, but the Sun has no orbital momentum around itself.
Flying past the Sun could give you velocity relative to the galactic center, making use of the Sun's orbit around that. But that velocity doesn't help you leave the Sun's neighborhood or travel within the Solar System, because the gained velocity is in the same direction as the Sun and Solar System are already moving.
My understanding (though I'm no astrophysicist) is that gravity boost from a planet works because of the relative velocities between the planet and the sun, whereas trying to use the sun's gravity to boost your solar system escape velocity would fail since gravity would be fighting you on the way out just as much as it was helping you on the way in.
Yes, this is basically correct. What a gravity boost from a planet does is transfer a very small amount of the planet's orbital kinetic energy to the spacecraft; it puts the planet into a slightly smaller orbit, and boosts the spacecraft to a higher speed on its way out. Since the Sun is what the planets are orbiting, this trick obviously won't work the same way with the Sun.
(Technically, the Sun itself, or more precisely the center of mass of the Solar System, is orbiting the center of the galaxy; so I suppose it would be theoretically possible to fly a spacecraft by the Sun in such a way as to transfer a very small amount of its orbital kinetic energy with respect to the center of the galaxy to the spacecraft, so it would fly outward faster than it went in, even after taking into account the slowdown climbing out of the Sun's gravity well. But I doubt we're going to be in any practical position to try this any time soon.)
For those who don't know what a gravity boost is, here is the simple picture.
In the reference frame of the planet you will travel in a hyperbola as you go by. The incoming branch is from the front of the planet, the outgoing branch is also in the front of the planet. So you go from moving backwards to moving forwards.
However the planet is moving in the reference frame of the Sun. The initial "moving backwards" is actually more like "sitting there". The ending "moving forwards" is actually something like, "moving up to 2x as fast as the planet".
So a gravity boost only looks like a gravity boost in a reference frame that is moving relative to the object. Furthermore the gravity boost also does nothing to help you to escape from the object you're getting the gravity boost from.
Therefore we cannot get a gravity boost from the Sun to leave the Solar System. And a gravity boost from the Sun does not look like a gravity boost to us, in orbit around the Sun.
You can go look it up, but IIRC, the slingshot method (using a rare alignment of planets) produced a higher "speed" (so to speak) than would be reasonable to produce even with today's technology. (i.e taking the same budget today and doing everything we can to get a probe out at the same "speed" would be impossible).
I'm not sure if it's actually impossible. IANA physicist, but if your singular all-consuming goal was to get out of the solar system as fast as possible you could probably get a better gravity assist from a single pass of the sun than Voyager got from the entire grand tour.
(Feel free to correct me, physicists!)
The bigger issue is convincing someone to hand you millions of dollars to literally throw away faster than anything in prior human history.
Well, technically most of the mission cost would be spend on Earth (paying Earth engineer salaries, and Earth factory bills), so the money never leaves Earth. The only money you are literally throwing is the material cost of the rocket and probe, which would be fairly low (the cost of a bunch of titanium (or whatever the rocket/probe is made of), silicon not worth measuring, the rocket fuel (which is surprisingly cheap), etc.
> get a better gravity assist from a single pass of the sun
No. The gravity assist is because of the motion of the planets around the sun. The sun isn't moving relative to itself. There are some other things you can do where the sun can help, but not a slingshot.
Provided it survives that far out, New Horizons is likely to follow the Voyager probes in exploring the outer heliosphere and mapping the heliosheath and heliopause.
Even though it was launched far faster than any outward probe before it, New Horizons will never overtake Voyager 1 as the most distant man-made object from Earth. Close fly-bys of Saturn and Titan gave Voyager 1 an advantage with its extra gravity assist. When New Horizons reaches the distance of 100 AU, it will be travelling at about 13 km/s (29,000 mph), around 4 km/s (8,900 mph) slower than Voyager 1 at that distance.
We could but it wouldn't be easy. Likely what we'd do is use a really big rocket like the Delta IV Heavy or the upcoming Falcon Heavy to give the spacecraft a lot of extra speed. Then we'd use electric propulsion on the craft itself to continue to build up speed over its life. Ultimately, even with today's technology, we could catch up to these probes but it would take decades to do so.
