Nasa worth it? (thread split)

[Kryssan]

No, more like disappointed. I was making an earnest attempt to learn something new and nothing resulted from it. No tears here.

The easiest answer is something I alluded to earlier with my gaming discussion. It's not how we envision our scifi ships, but you really need engines at both ends ( some of the ships at the beginning of Nexus TJI had such a setup ). Engines with equivalent power, at that. You're going to spend the same amount of time accelerating in the forward and reverse direction.

Which realistically means that, were you capable of achieving near c velocities ( and beyond? ) you'd spend most of your time accelerating which means burning fuel, which of course lends to yet another problem. Your actual trip time would also change for the worse as well, since you would only spend a fraction of it at potential relativistic ( and beyond? ) speeds.

I forget where exactly the 'flip end for end' idea came from, but it was essentially the 'accepted answer' for having your ship's engines only on one end of the ship while still satisfying the laws of motion. However, the stresses that you would impose on the ship's hull doing so makes it a bad idea anyway.

Too bad Lagrangian points don't actually open portals to FTL travel, eh? Then all we'd need is an LDS / cruising drive.

[Seraph]

The best road trips are always the ones where you have to start slowing down when you get about halfway to where you are going.

[TummieGaruda]

Speaking of Lagrangian points, anyone here looking forward to the JWST? It is a beast of a telescope, but my biggest concern is NASA's previous track record with the Hubble Optics and the fact that once they get the JWST out there, I doubt they will be able to do any service on it should there be a problem.

[Niiro]

There is no drag in a vacuum, so a chute will not slow things down like it can or does here on Earth. Unless like you stated earlier, if you were flying towards another star that was ejecting particles in that hypothetical direction, but that would slow you down so slowly it wouldnt be worth the effort.

Yea obviously it wouldn't be catching wind resistance, it's just conceptually wind to a regular sail and light to a solar sail work more or less the same, as long as there's enough of it coming from the right direction you can use it. One nice thing about solar radiation is it's much more consistent than the weather.

[archibaldcrane]

Problem is if you're using some concentrated laser shit from one direction to speed up to, say, .1c - you'd need the same amount of energy from the other direction to slow back down...but then WHO WAS LASER?

[Niiro]

It wasn't really in reference to how you would slow down from such high speeds, the comment was just pointing out that a solar sail actually could be used like a parachute in order to slow something down.

Like someone said earlier until you actually have the tech to get something going that fast there's not much to be said about how you're gonna slow it down.

[quannum]

name the science forum "Space Brakes"?

[BaneTheBrawler]

Make like EVE and invent a Warp Drive that, when not actively moving your vessel faster than light, creates drag against one of the various fields permeating the universe. Two birds, one stone!

[archibaldcrane]

67 million mph, let's do this.

Hmmm, so if my calculations are correct, if you accelerate continuously at 1G (9.8m/s squared) - meaning you'd kinda get to stand up and be normal or whatever on the ship like you're on earth, and you do that for 35 days, you'd reach 67 million mph - 1/10th the speed of light. So yeah, you'd just have a little over a month of acceleration and slowdown on either end, and then just cruise for 45 years in between, and BAM - reach a planet in a new galaxy.

[Drex]

Problem is if you're using some concentrated laser shit from one direction to speed up to, say, .1c - you'd need the same amount of energy from the other direction to slow back down...but then WHO WAS LASER?

one laser on each side of the sail. don't forget to plug the extension cord into itself for infinite laser power.

[Mizango]

Oh.

http://www.space.com/19565-worlds-la...sunjammer.html

[archibaldcrane]

Damn, only .01 Newtons of force? That's like 1000 times less force than you need to get to .1c in a month...

[Mizango]

I know, right? Dope.

[archibaldcrane]

And the further you are from the sun the less force it would generate right? Also, say you're going .05c, getting laser-assisted across the solar system - would you only be getting 95% of that laser energy compared to if you were going, like, 10 mph? Like, the laser light is hitting the receptor "less quickly" since you're moving away from it at 1/20th of its speed?

[Qalbert]

why can't they just make solar oars

[Niiro]

Because then we'd need solar powered oarsmen.

[Qalbert]

guidos, it's like gym and tan in one

[Howie Roary]

g.t.o.

[Niiro]

guidos, it's like gym and tan in one

I'm not sure if it'll work but I'm willing to send as many as necessary into the vacuum of space until we figure it out.

They may not be as smart as test chimps but they're infinitely more disposable.

[Mizango]

And the further you are from the sun the less force it would generate right? Also, say you're going .05c, getting laser-assisted across the solar system - would you only be getting 95% of that laser energy compared to if you were going, like, 10 mph? Like, the laser light is hitting the receptor "less quickly" since you're moving away from it at 1/20th of its speed?

Correct