Photon Thruster cuts Mars travel time to 7 days

theotherguy

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TUSTIN, Calif., Sept. 7, 2007 -- An amplified photon thruster that could potentially shorten the trip to Mars from six months to a week has reportedly attracted the attention of aerospace agencies and contractors.

Young Bae, founder of the Bae Institute in Tustin, Calif., first demonstrated his photonic laser thruster (PLT), which he built with off-the-shelf components, in December.


“This is the tip of the iceberg," Bae said in a statement from the institute. "PLT has immense potential for the aerospace industry. For example, PLT-powered spacecraft could transit the 100 million km to Mars in less than a week.”


Bae will present at the AIAA SPACE 2007 Conference & Exposition, to be held Sept. 18-19 in Long Beach, at four sessions: Space Transportation Systems, Promising Space Concepts from the NASA Institute of Advanced Concepts (NIAC), Space Systems for the Next 50 Years, and Advanced Vehicle Systems.
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bae2.gif


Source:
http://www.photonics.com/content/news/2007/September/7/88894.aspx

wow!

When working for NASA I got to view the prototype of the VASIMIR plasma engine, which would cut travel times to mars from 6 months to 39 days. But this? Seven days? That's utterly incredible.

The future of interplanetary space flight look bright indeed. With ion, plasma and now photon engines, we should be seeing a new array of previously unimaginable probes and human spacecraft for the exploration of our solar system and beyond.
 
I am not so sure about this. This is just a bit rediculous to believe.
 
yeah, this sounds a bit far-fetched, but y'know.

****ING AWESOME! ECONOMICALLY VIABLE SPACE TRAVEL IN OUR LIFETIMES.
 
I'll agree with the rest, this seems crazy, but hell if it works, **** YEAH!
 
How many of these thrusters does it take to achieve that result? What if they added more to increase the speed even further? Or does that not work in space?
 
Raziaar said:
How many of these thrusters does it take to achieve that result? What if they added more to increase the speed even further? Or does that not work in space?
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More thrusters = More mass. So you need more thrust to combat the added mass. There comes a point where adding more simply isn't worth it.
 
Kyorisu said:
More thrusters = More weight. So you need more thrust to combat the added weight. There comes a point where adding more simply isn't worth it.
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But if space is weightless, what's more weight going to do?
 
15357 said:
mass =/= weight
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Still, why would adding more hinder a shuttle in space? Sure, you can only go so fast, but I don't understand the whole "more mass = less efficient in space" idea....then again, I'm no science guy, so this is why I ask :)
 
The greater the mass, the greater the energy required to move it.

Weightlessness in space just means that there's no gravitational forces acting on said mass (like the one we experience on Earth)
 
If the thrust produced is more than the energy required to overcome the inertia of the engine then, the engine will have positive contribution to the momentum of the spacecraft. I'm not sure there is such thing as terminal velocity in a vacuum so I don't think there is a point in which adding more engines will stop being effective, engine number will be more a question of economics.
 
hmm...sounds interesting, but i'll wait for some further research.

As stabby mentioned...if the engine produces enough thrust to overcome the inertia of the mass then you have a positive force which pushes the object.
 
15357 said:
mass =/= weight
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Err yeah. I have not done any physics in ages. One tends to miss the details on occasion.

Mr Stabby said:
If the thrust produced is more than the energy required to overcome the inertia of the engine then, the engine will have positive contribution to the momentum of the spacecraft. I'm not sure there is such thing as terminal velocity in a vacuum so I don't think there is a point in which adding more engines will stop being effective, engine number will be more a question of economics.
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All well and good if you build the vehicle in space.
 
There's another problem with this too, and that is the energy requirements. How would you power such an engine? There's no current power source that could accelerate a spacecraft to such speeds, and we probably won't have it until we get really effective fusion reactors and/or those promised antimatter-drive.
 
We could assemble the rocket on the moon, and then launch it from there. It would take much less energy, so it might be worth it.
 
This is very awesome. If this works like they plan, then it's seriously amazing.
 
Fabulous!

Hope to see public Space Travel in my lifetime a la Aliens etc.
 
kattmat said:
There's another problem with this too, and that is the energy requirements. How would you power such an engine? There's no current power source that could accelerate a spacecraft to such speeds, and we probably won't have it until we get really effective fusion reactors and/or those promised antimatter-drive.
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I was looking at another press release, and he says that if the engine were scaled up it could be powered by a small nuclear reactor, which would give it enough thrust to push 60 tons over its own mass to the speed necessary.
 
kirovman said:
Assemble it in orbit.
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Space elevator FTW.


Is this one of those things where the photons are effectively pushing the spacecraft? I would have thought that was impossible, seeing as photons don't have mass (or do they?). It they do have mass, then wouldn't firing photons at yourself to push you one way be like squirting a water pistol at yourself for the same reason, in principle? Because of the whole 3rd law of motion, I mean. When you squirt the water pistol, the recoil would be the same as the force you get when the water hits you. Unless it's like just firing a laser out into space, which would be like squirting a water pistol and letting the recoil push along. That makes more sense.

I'd like to see how this actually works though, as it doesn't seem to be just a laser firing into space.

If the equation for acceleration isn't acceleration = force/mass, stop reading now. If it is, then adding more thrusters of the same power would eventually be pointless. It would be like:
mass of spacecraft = 10
mass of thruster = 2
force of thruster = 5

1 thruster: acceleration = 5/12 = 0.41
2 thrusters: acceleration = 10/14 = 0.71 up by .3
3 thrusters: acceleration = 15/16 = 0.93 up by .22
4 thrusters: acceleration = 20/18 = 1.11 up by .17
5 thrusters: acceleration = 25/20 = 1.25 up by .14
6 thrusters: acceleration = 30/22 = 1.36 up by .11
7 thrusters: acceleration = 35/24 = 1.45 up by .09
8 thrusters: acceleration = 40/26 = 1.53 up by .08

So yeah, eventually it would be pointless.
 
Godron said:
Space elevator FTW.


Is this one of those things where the photons are effectively pushing the spacecraft? I would have thought that was impossible, seeing as photons don't have mass (or do they?). It they do have mass, then wouldn't firing photons at yourself to push you one way be like squirting a water pistol at yourself for the same reason, in principle? Because of the whole 3rd law of motion, I mean. When you squirt the water pistol, the recoil would be the same as the force you get when the water hits you. Unless it's like just firing a laser out into space, which would be like squirting a water pistol and letting the recoil push along. That makes more sense.

I'd like to see how this actually works though, as it doesn't seem to be just a laser firing into space.

If the equation for acceleration isn't acceleration = force/mass, stop reading now. If it is, then adding more thrusters of the same power would eventually be pointless. It would be like:
mass of spacecraft = 10
mass of thruster = 2
force of thruster = 5

1 thruster: acceleration = 5/12 = 0.41
2 thrusters: acceleration = 10/14 = 0.71 up by .3
3 thrusters: acceleration = 15/16 = 0.93 up by .22
4 thrusters: acceleration = 20/18 = 1.11 up by .17
5 thrusters: acceleration = 25/20 = 1.25 up by .14
6 thrusters: acceleration = 30/22 = 1.36 up by .11
7 thrusters: acceleration = 35/24 = 1.45 up by .09
8 thrusters: acceleration = 40/26 = 1.53 up by .08

So yeah, eventually it would be pointless.
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sorry but where did you get the 5?
 
Woah I just invented a thruster that runs on daisies! It goes to pluto in 4 hours!
 
lePobz said:
Can I bolt a few of these to the back of my car?
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You can, but if it's anything like an ion thruster: it will produce a force equal to a sheet of paper resting on your hand. So the weight of the thing would just slow you down, it's only useful in space.
 
PvtRyan said:
You can, but if it's anything like an ion thruster: it will produce a force equal to a sheet of paper resting on your hand. So the weight of the thing would just slow you down, it's only useful in space.
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That's ok, it's a space car.
 
Godron said:
Space elevator FTW.


Is this one of those things where the photons are effectively pushing the spacecraft? I would have thought that was impossible, seeing as photons don't have mass (or do they?). It they do have mass, then wouldn't firing photons at yourself to push you one way be like squirting a water pistol at yourself for the same reason, in principle? Because of the whole 3rd law of motion, I mean. When you squirt the water pistol, the recoil would be the same as the force you get when the water hits you. Unless it's like just firing a laser out into space, which would be like squirting a water pistol and letting the recoil push along. That makes more sense.

I'd like to see how this actually works though, as it doesn't seem to be just a laser firing into space.

If the equation for acceleration isn't acceleration = force/mass, stop reading now. If it is, then adding more thrusters of the same power would eventually be pointless. It would be like:
mass of spacecraft = 10
mass of thruster = 2
force of thruster = 5

1 thruster: acceleration = 5/12 = 0.41
2 thrusters: acceleration = 10/14 = 0.71 up by .3
3 thrusters: acceleration = 15/16 = 0.93 up by .22
4 thrusters: acceleration = 20/18 = 1.11 up by .17
5 thrusters: acceleration = 25/20 = 1.25 up by .14
6 thrusters: acceleration = 30/22 = 1.36 up by .11
7 thrusters: acceleration = 35/24 = 1.45 up by .09
8 thrusters: acceleration = 40/26 = 1.53 up by .08

So yeah, eventually it would be pointless.
Click to expand...

I was reading more about it, and apparently it works by bouncing a laser many thousands of times between two spacecraft or between a spacecraft and earth.

Photons have no mass, but they transmit momentum and energy to matter when they collide (albeit a TINY amount of momentum). It's one of the strangest oddities of quantum physics. The idea is to have the spacecraft jettison a laser and have the laser fire at a mirror on the spacecraft. The laser would bounce back and forth many thousands of times, building up the thrust slowly. The laser and the ship would then travel in opposite directions with the same amount of force. Given enough power and time, a spacecraft could theoretically advance up to the speed of light.

The only thing that Bae did to improve this photon thruster was to vastly increase the efficiency of the reflecting laser, and amplify the intensity of the beam. His small 10W laser apparently is able to create a thrust of 45 microNewtons, which is about as much thrust as the most powerful industrial and weapons-grade lasers can produce. The thrust achieved using his method is about 3,000 times more than that of conventional lasers of similar wattage.

His immediate plan with this thruster is to make extremely accurate precision guidance for satellites, which could fly in formation by bouncing lasers off of each other.
 
It would still be about 7791 years until we would be able to reach alpha centauri.
 
delusional said:
It would still be about 7791 years until we would be able to reach alpha centauri.
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That's not an impossibility. We send away a huge spaceship that has everything needed to survive, then 300 generations later they've reached it.
 
The Monkey said:
That's not an impossibility. We send away a huge spaceship that has everything needed to survive, then 300 generations later they've reached it.
Click to expand...

Odds are in 300 generations we will have technology surpassing photon thrusters and the entire mission becomes obsolete.
 
Smoke said:
Odds are in 300 generations we will have technology surpassing photon thrusters and the entire mission becomes obsolete.
Click to expand...
If we thought like that we never would've gotten anything done.

Still, after 300 generations in space, the civilization on the ship might be a little bizarre.
 
I'm not suggestiong it's a bad idea, just pointing out that the ship will most likley be overtaken before it gets there by bigger, faster, more efficient colony ships.
 
Does anyone else hate it when people say interstellar and intergalactic travel are impossible? Its like "facepalm no wai ships will never get better and will never get faster". :dozey:
 
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