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I want to say there has been some discussion about space travel to other worlds and "leaving too soon", ie - if you launch today, a space craft that launches to

I want to say there has been some discussion about space travel to other worlds and "leaving too soon", ie - if you launch today, a space craft that launches to the same destination a year from now would beat you there, because the technology would have progressed to the point that the later ship was much faster. If we were to launch a state of the art probe today, how long would it take to get to where voyager 1 is now after 35 years of travel?

rthomas6 14y ago
Conversely, this means that it's hard to find the optimal time of launch, since waiting would always provide a better launch in the future.
- wiredfool 14y ago
  Well, since most of the speed is from slingshot gravitational interactions, there's 2 parts to it. * How well are the planets aligned * How well can you exploit that Some of the current probes have done multiple flybys of inner solar system bodies to boost speed to reach the outer planets. Voyager 1 and 2 had a relatively direct route to take advantage of a once in a lifetime alignment of the outer planets.
  - rthomas6 14y ago
    That takes care of the optimization problem, then. :)
ISL 14y ago
About the same. New Horizons was faster at launch, but the real boosts come from gravitational assists. Clever choices of orbits buy you speed - stealing an infinitesimal fraction of Jupiter's momentum is much more efficient than any propulsion technology in use. If that ever changes, then "too soon" will have become reality. From http://en.wikipedia.org/wiki/New_Horizons http://en.wikipedia.org/wiki/New_Horizons "New Horizons is often given the title of Fastest Spacecraft Ever Launched, although the Helios probes are arguably the holders of that title as a result of speed gained while falling toward the Sun. New Horizons, however, achieved the highest launch velocity and thus left Earth faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate velocity of 16.5 km/s (36,900 mph), plus losses, all to be provided by the launcher. However, it will not be the fastest spacecraft to leave the Solar System. This record is held by Voyager 1, currently travelling at 17.145 km/s (38,400 mph) relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity from Jupiter and Saturn gravitational slingshots than New Horizons. Other spacecraft, such as Helios 1 & 2, can also be measured as the fastest objects, due to their orbital velocity relative to the Sun at perihelion. However, because they remain in solar orbit, their orbital energy relative to the Sun is lower than the five probes, and three other third stages on hyperbolic trajectories, including New Horizons, that achieved solar escape velocity, as the Sun has a much deeper gravitational well than Earth."
drcube 14y ago
For that matter, why did anyone buy computers when waiting just a little longer brought cheaper, faster, and better computers? Well, for one thing, if nobody bought computers, they wouldn't have gotten any faster, since no one would have built them. And if nobody launched space probes, they wouldn't have gotten faster, because no one would have made them.

rthomas6 14y ago

Conversely, this means that it's hard to find the optimal time of launch, since waiting would always provide a better launch in the future.

wiredfool 14y ago
Well, since most of the speed is from slingshot gravitational interactions, there's 2 parts to it. * How well are the planets aligned * How well can you exploit that Some of the current probes have done multiple flybys of inner solar system bodies to boost speed to reach the outer planets. Voyager 1 and 2 had a relatively direct route to take advantage of a once in a lifetime alignment of the outer planets.
- rthomas6 14y ago
  That takes care of the optimization problem, then. :)

ISL 14y ago

About the same. New Horizons was faster at launch, but the real boosts come from gravitational assists. Clever choices of orbits buy you speed - stealing an infinitesimal fraction of Jupiter's momentum is much more efficient than any propulsion technology in use. If that ever changes, then "too soon" will have become reality. From http://en.wikipedia.org/wiki/New_Horizons http://en.wikipedia.org/wiki/New_Horizons "New Horizons is often given the title of Fastest Spacecraft Ever Launched, although the Helios probes are arguably the holders of that title as a result of speed gained while falling toward the Sun. New Horizons, however, achieved the highest launch velocity and thus left Earth faster than any other spacecraft to date. It is also the first spacecraft launched directly into a solar escape trajectory, which requires an approximate velocity of 16.5 km/s (36,900 mph), plus losses, all to be provided by the launcher. However, it will not be the fastest spacecraft to leave the Solar System. This record is held by Voyager 1, currently travelling at 17.145 km/s (38,400 mph) relative to the Sun. Voyager 1 attained greater hyperbolic excess velocity from Jupiter and Saturn gravitational slingshots than New Horizons. Other spacecraft, such as Helios 1 & 2, can also be measured as the fastest objects, due to their orbital velocity relative to the Sun at perihelion. However, because they remain in solar orbit, their orbital energy relative to the Sun is lower than the five probes, and three other third stages on hyperbolic trajectories, including New Horizons, that achieved solar escape velocity, as the Sun has a much deeper gravitational well than Earth."

drcube 14y ago

For that matter, why did anyone buy computers when waiting just a little longer brought cheaper, faster, and better computers? Well, for one thing, if nobody bought computers, they wouldn't have gotten any faster, since no one would have built them. And if nobody launched space probes, they wouldn't have gotten faster, because no one would have made them.