Bae Institute crafts magical photonic laser thruster

Now that humans have shot themselves up into space, frolicked on the moon, and have their own space station just chillin' in the middle of the galaxy, what's really left to accomplish out there? How about cruising around at light speed? Apparently, a boastful group of scientists at the Bae Institute in Southern California feel that they're one step closer to achieving the impossible, as the "world's first photonic laser thruster" was purportedly demonstrated. Using a photonic laser and a sophisticated photon beam amplification system, Dr. Bae reportedly "demonstrated that photonic energy could generate amplified thrust between two spacecraft by bouncing photons many thousands of times between them." The Photonic Laser Thruster (PLT) was constructed with off-the-shelf parts and a bit of fairy dust, and it's said that this invention could eliminate the need for "other propellants" on a wide range of NASA spacecrafts, theoretically savings millions on energy costs and enabling longer missions. So while this may be an incredibly novel idea, the chances of this actually working outside of a laboratory seem relatively small, and make sure we're not the guinea pigs strapped into the first craft that utilizes this mystical method of launching, cool?

[Via Wired]

[Mike @ Feb 24th 2007 1:10PM]

I dunno about inter-galactic travel, but I'd like to mount that to the heads of a couple of fricken sharks...

[EdZ @ Feb 24th 2007 1:21PM]

Isn't 'photonic laser' redundant?

[Gumby @ Feb 24th 2007 1:36PM]

Laser powered spacecraft have been around since last century.

http://www.lightcrafttechnologies.com/media.html

At least those looked cool and they have working prototypes. I had lunch with the guy that invented them. Smart guy.

[JP @ Feb 24th 2007 3:36PM]

Correct me if I'm wrong, but doesn't this system work by heating up air under the vehicle so the air expands rapidly and pushes it forward?

Spelling mistakes may occure, because english is not my native language.

[Josh Warner @ Feb 24th 2007 1:53PM]

Photonic laser is not redundant anymore; lasing has been proven with particles that have mass (electrons, and more recently even molecular lasers). This isn't general knowledge but in the field it is accepted.

Summary is misleading. Nothing is going to be launching by this system anytime soon (if ever) - the power requirements would still be immense, even with his greater amplification, not to mention that it needs a resonance to work which atmosphere would seriously disrupt - but it would be ideal for small spacecraft adjustments (as TFA states). The propellant they speak of saving wouldn't be main propellant, rather the chemical propellant for thrusters that is currently problematic (this allows for theoretically infinite course adjustments so long as the craft has power, where chemical propellant is used up).

The main problem with it that I can see it is the fact that it requires a resonance between two spacecraft. That will work for specifically designed missions such as pairs of satellites (ideal, because many small precise adjustments would be easy with this thing), but it isn't a general purpose thruster, at least not yet.

[Josh Warner @ Feb 24th 2007 3:55PM]

It works in a vacuum. Therefore, it can't be using the heating of air.

I'm pretty sure this works on the concept of conservation of momentum. Photons do carry momentum (not the p=m*v kind, I'm talking about relativistic 4-momentum), although it is a small amount so we don't usually think of a 'pressure' due to a light bulb. However, intense lasers can be thought of in this way and do in fact create thrust. This is the 'best' thrust, because the velocity of the 'particles' (photons) is the speed of light, allowing for maximal possible terminal velocities.

[Bultie @ Feb 24th 2007 5:50PM]

I refered to the comment above, that was ponting out a similar technology had been invented before.

It would be interesting to know if it wasn't more effective using electrons instead of photons, because they have at leat a Mass.
2000 electrons have the mass of a proton (which is equal to one Hydrogen atom) and they can reach speeds close to the speed of light. So you should move forward if you lash a microwave at the back of your spacecraft.

And by the way, don't mind those douchbags, some appear on every commentthread.

[mr friggles @ Feb 24th 2007 4:29PM]

WoW...tHaT last sentence...just wOw...

This is a perfect example of the "control system" that rules over or society, making sure we can't even conceive of what is not DEFINED to us as possible.

[Johnny Halfcock @ Feb 24th 2007 4:51PM]

I am a racist, please spam me: [e-mail]

[Josh Warner @ Feb 24th 2007 5:27PM]

@ Johnny (racist) Halfcock:
I am a physics student. Can you say the same?

If I phrased it "Maximal velocity" would you be happier? No, because you don't know what you're talking about. The maximum velocity of any propulsion system is dependent on the velocity of its exhaust particles. Chemical propellant as used to launch conventional rockets provides tremendous thrust - but those particles actually aren't traveling very fast. The expected value of the velocity of the exhaust is the effective maximum velocity of the engine, because it cannot propel the craft any faster than the fastest (on average) thing it is emitting.

This is why antimatter/laser drives would be great, because the particles emitted would be very close to light speed so the theoretical maximum velocity would approach c (can't get there because the craft has mass, but can approach it).

Oh, and I'm reporting your comment for racism. I like sharing my knowledge, but people like you make me feel like never posting again. You don't deserve to hear what I've spent years learning.

[Edward @ Feb 25th 2007 12:03AM]

you arn't the only one. i reported him too. i'm taking introductory physics and your explanation was very interesting! thank you, and please know your comments are greatly appreciated!

[Johnny Halfcock @ Feb 24th 2007 5:55PM]

I am a racist, please spam me: [e-mail]

[Bultie @ Feb 24th 2007 6:17PM]

Really funny fantasy name, I have to admit that…nah…not really . Get a life, instead of continuing your very honorable but lonely fight against intelligence.
Why are you hanging out at engadget anyway if you hate all those themes?

[Chris @ Feb 24th 2007 9:15PM]

Johnny Halfcock, what the fuck is wrong with you? You shouldn't be banned from the internet, you should be banned from Earth. In fact, you should be the first guinea pig on a laser propelled rocket.

[Al Pi @ Feb 25th 2007 12:26AM]

What's sad is that I'm from Alabama and don't hear the "n" word thrown in a week as much as that guy slung it in a single post. Kinda sad that it's how he chooses to represent UC Berkeley.

Anyhow, hasn't there been theorizaton/design on like catching solar wind as a form of propulsion -- which more or less seems like the same sort of thing, only less concentrated and on a larger scale... right?

[Bultie @ Feb 25th 2007 7:45AM]

Not exacly.
There was already a prototype, but the launch (made by a russian submarine in one of those rockets which normaly carrys nuclear bombs) failed miserably.
Solar wind is a combination of alpha radiation, protons, elektrons and other ionised atoms.
So it has much more mass than light ^^, the sun looses about one milllion tones of its mass per second via the solar wind.

[cjameshuff @ Feb 27th 2007 10:12AM]

The solar wind certainly has more mass than sunlight, since light is massless. However, sunlight actually carries more momentum than the solar wind. (yes, photons have momentum even though they don't have mass) Solar sails operate by reflecting sunlight, the solar wind does not come into play. (Though there is another possible method of propulsion, "mini-magnetospheric plasma propulsion", which uses a large magnetic field to catch the solar wind, hopefully with less mass than a solar sail that gives similar thrust.)

This is indeed a photon drive, using the momentum of photons to provide thrust. Exactly the same principle as a solar sail, except that the light comes from a focused laser and can thus be pointed in whatever direction that is desired, as well as being far more intense than sunlight, allowing much smaller reflectors to be used. Both reflectors are pushed away from each other, but one of them could be a launch station with heavy, high-capacity power sources and lasers placed in a convenient orbit and kept supplied with stationkeeping fuel, launching packages which themselves do not need to carry big thrusters or the power sources to run them, and can thus be made much lighter and cheaper.

Josh Warner is correct about the performance of photon thrusters. The "delta-v" of a spacecraft is how much it can change its velocity with its engine and the fuel it can carry. Throwing lighter particles of fuel out the back at higher velocities takes more energy, but provides a higher delta-v for the same spacecraft mass. The limit of this is shining a beam of photons out the back, which takes a lot of energy to produce any useful thrust, but also expends no massive fuel. This laser thruster is even better, as the photons don't have to be generated on board the spacecraft...a refinement that makes the photon drive much more practical. Look around for information on "specific impulse" for more information.

[mark welch @ Feb 25th 2007 9:55PM]

halfcock? I bet he doesn't even have a quarter cock.

[Greg Zapp @ Feb 26th 2007 3:51PM]

Don't know if anybody mentioned this but, as cool as this stuff is... you can't propel anything of significant mass to the speed of light. The energy requirments for exeleratoin approach infinity as you approach the speed of light. Also some current theories provide that as your spatial velocity increases the speed of your time progression decreases so that both are equiv to light speed. So if you somehow reached light speed spatialy, your time speed would have to be 0(which of course means you aint going nowhere and probably something bad would happen lol).

[Dan Frederiksen @ Mar 1st 2007 8:08AM]

It's bullshit
from what I gather it's dependent on very good laser reflection contact between two space objects in order to work. that's going to be difficult over a million of kilometers not to mention make course corrections a bitch. it's crap, completely void of ambition. nasa would be proud