Now, this is really interesting

Ars Technica reports a planet may have been found in orbit around one of the stars in the Centauri system, the closest stars to the Sun at about 4.5 light years away:

http://arstechnica.com/science/2012/10/exoplanet-found-right-next-door-in-alpha-centauri/

In the last paragraph, the question of a probe is raised:

Quote:

[..]any probe we sent wouldn't arrive for about 40,000 years. So that's probably a no-go, "given our propensity for instant gratification." But there are some unproven propulsion ideas that could get us there much more quickly, [..]

Offhand I can think of 4 ways with achievable technology to get there, and back even, within a human lifespan (solar sail, ion engine, nuclear propulsion and, of course, Orion <w>). It would also be possible, thou less likely, with most of these to make the trip in less than 10 years one-way. Not immediately possible, no, but in a few years almost certain.

Anyway, knowing there are planets there is a good reason to go. Sure, advances in astronomy will yield lots of valuable information soon (a lot sooner than a probe would). But a probe can find out a great deal more detail.

It's something to think about...

You think there is an achievable way with the methods you mentioned to travel 4.5 light years in less than 10 years?
Disagree.
Speed of light is approx 700 million miles per hour.
To reach 4.5 light years in less than 10 years would require speeds over 300 million mph.

Get close to 0.5c, of course. It's the law ;)

The problem with going somewhere that far that fast is that you have to stop. You can't get much science done at half the speed of light. All of the fuel to accelerate and the decelerate would have to come from space. There's no way you can carry that much fuel with you even if it were free. We'll just have to wait for the Centauri to invade Earth.

Quote: s2dbaker

The problem with going somewhere that far that fast is that you have to stop. You can't get much science done at half the speed of light. All of the fuel to accelerate and the decelerate would have to come from space. There's no way you can carry that much fuel with you even if it were free. We'll just have to wait for the Centauri to invade Earth.

Ion/"Solar"

Quote: s2dbaker

All of the fuel to accelerate and the decelerate would have to come from space. There's no way you can carry that much fuel with you even if it were free. We'll just have to wait for the Centauri to invade Earth.

The Cantauri have to stop, too. It's hard to invade a planet when you're moving at 05 c....

Seriously, you don't need fuel to stop, necessarily. There's friction.

So let's say you can't build a solar sail, and you don't want Orian (why not? well...) Then you're stuck with either ion or nuclear. Fine. Both have a very efficient thrust to weight ratio. So, you slow down some with your engines, then make for the nearest gas giant and use aerobraking.

This assumes a sub-optimal thrust-and-coast kind of journey, like the Apollo Moon shots did. An ion or nuclear drive could do a continuous thrust trip. That is, you accelerate all the way to mid point, reverse direction of the trust and deccelerate the rest of the way. I know it's counter-intuitive, but that's the fastest way to travel in space (barring wormholes, hyperdrives, warp drives, and other fantasies).

BTW by "a few years" I mean something like 30 to 50 years, not within the rest of the decade or early in the 2020s.

The mission would need to be HUGE. You'll want one or two probes to remain in space and fly around the system, plus a stable transmitter (no small matter in a triple star system plus planets), and some landers. Ho amny landers depends on how many planets there are out there. if it's just one superhot gas giant, well, who cares. But if you have six or ten rocky worlds, you'll definitely want to land in some of them.

Quote: Nareed

Offhand I can think of 4 ways with achievable technology to get there, and back even, within a human lifespan .

I assume you're still talking unmmaned flight.

But just for kicks, imagine this scenario. Turning on your TV, or watching on the Internet in 2012, of the 1969's crew of Apollo just now landing on some planet today.

*yeah, we send them as teens.


And that's for the short trips.

Would there be any advantage to sending instruments like Hubble or other types of deep seeing/listening probes into deep space as fast as we can make them go rather than trying to get an object all the way to the destination first?

Quote: rxwine

Would there be any advantage to sending instruments like Hubble or other types of deep seeing/listening probes into deep space as fast as we can make them go rather than trying to get an object all the way to the destination first?

Not to the centauri system.

4.5 light years is a stone's throw as interstellar distances go (and practically contiguous as intergalactic distances go). If there are planets there, we should have images of them within a decade. We could probably even determine their atmospheric and surface composition with some degree of certainty, all from ground-based telescopes and a space-based interferometer.

For going to Alpha, Beta and Proxima Centauri, I think what would work best would be the current Mars exploration model. That is, send several craft one after the next over years. That would be more economical than sending one BIG mission with all the trimmings, plus we could adjust for new discoveries. Say a planet has an extensive ocean. We can then scrap some rovers and replace them surface ships or submarines.

Oh, this is an old ide aI had: if we could travel FTL (faster than light), it would make a great deal of sense to send big telescopes to systems farther away than Earth from events that took palce before the modern astronomy era. For example, we could send one 450+ light years away to see Tycho's Supernova. Or 1100 light years to see another big Supernova.

Better yet, if we catch a supernova, say, 15,000 light years away tomorrow, then we can send probes proggresively closer and farther from the event, and get the full evolution of the explosion and aftermath all at once (or nearly so).

Say a star that has no business blowing up according to current theories nevertheless does blow up. Well, head in the opposite direction from that star and watch it for years, as long as needed, and you can better try to determine why it blew up.

deleted

Quote: rxwine

But just for kicks, imagine this scenario. Turning on your TV, or watching on the Internet in 2012, of the 1969's crew of Apollo just now landing on some planet today.

That's an average speed of about 0.10 c. I don't know what the realtivistic effects would amount to, but probably the crew wouldn't gain more than a month or two at best. Of course they'd die on the way back, or on Centauri...