Photonic Laser Thruster Promises Earth to Mars in a Week 413
serutan writes "Using lasers to drive spaceships has been a subject of interest for many years, but making a photonic engine powerful enough for practical use has been elusive. Dr. Young Bae, a California physicist, has built a demonstration photonic laser thruster that produces enough thrust to micro-maneuver a satellite. This would be useful in high-precision formation flying, such as using a fleet of satellites to form a space telescope with a large virtual aperture. Scaled up, a similar engine could speed a spacecraft to Mars in less than a week."
acceleration? (Score:5, Insightful)
All a matter of scale... (Score:5, Insightful)
Small scale thrusters using only lasers is a good start, but we'll have to see what else gets bigger with scale, other than just the thrust.
Re:How "scaled up" is this? (Score:4, Insightful)
Energy source? (Score:5, Insightful)
Since you're dealing with a photon drive, the reaction mass usage (as determined by the classic rocket equation) is going to be negligible for the speeds required for interplanetary travel.
In fact, I'm not sure what the reaction mass would be in this case.
But in any case, you're going to need a lot of energy to create that photon thrust. Great phrigging big reactors, which means great, great, phrigging big radiators since you don't have the luxury of a river to carry away your waste heat.
Antimatter might be a compact way to store the required energy, but converting the gamma rays from matter/antimatter reactions to electricity is going to require heat exchangers and great big radiators as well.
Well, anyway, scaling this up is going to involve several bears of a problem.
Also, please note that this "article" is a press release from the guy who made the invention.
Power = Thrust * Exhaust Velocity (Score:5, Insightful)
Exhaust Velocity is the speed of light, or about 3*10^8 m/s.
So our power consumption is 3*10^13 Watts.
By comparison, the USA is currently consuming less than 1*10^13 Watts on average.
In other words, if think you think it costs too much to refuel an RV now...
It's not completely implausible to use light to propel a spacecraft, but either that propulsion will be ridiculously slow (e.g. solar sails, laser sails, or the "precisely tweak your satellite's orbit a tiny bit" applications mentioned in the article), or it's going to require ridiculous "cheap antimatter" amounts of energy.
Re:Solar system escape velocity! (Score:3, Insightful)
Twice the average speed if you want constant acceleration.
Re:acceleration? (Score:2, Insightful)
Minor correction (Score:4, Insightful)
So call it a mere 1.5*10^13 watts.
Re:I smell bullshit (Score:3, Insightful)
On the other hand even the current institutions started as someone creating them at some point.
And quite a lot of scientists were ridiculed by the establishment at a time they made a revolutionary discovery.
What worries me more is his unsubstantiated "if we just scale it up" argument. That doesn't stand basic math/logic/physics.
Re:acceleration? (Score:5, Insightful)
Re:acceleration? (Score:3, Insightful)
Re:I smell bullshit (Score:3, Insightful)
"Scaled up" (Score:4, Insightful)
Re:How "scaled up" is this? (Score:3, Insightful)
Re:acceleration? (Score:3, Insightful)
d
Re:How "scaled up" is this? (Score:5, Insightful)
Anybody who's read my posting history knows I'm a dyed-in-the-wool liberal, but I don't think we can singularly blame the GOP for this one. There's resistance to nuclear power coming from both extreme ends of the spectrum. Environmental activists who don't understand the science on the left, and oil industry lobbyists on the right.
I'm constantly frustrated with people who I know are well-intentioned and genuinely concerned, who are so afraid of nuclear power. I mean I agree, solar and wind power are great ideas, but right now we're generating power using f'ing COAL.
Re:acceleration? (Score:5, Insightful)
Remember, there's a big gap between "likely untrue" and "always untrue." When someone can look at their own statement, realize what it implies about their capacities, and then confidently declare "I am an idiot," they are displaying insight that is well above average, and certainly deserving of mod points.
I, for one, welcome our new self-insight-possessing commenters.
Staying out of the Politics and YRO threads may reduce your vitriol exposure by as much as 300%. Ask your doctor!
*Disclaimer: poster is a frequent and vitriolic contributor to Politics and YRO threads.
Re:acceleration? (Score:3, Insightful)
Well, since this is a science article, let us use the awesome power of experimental empirical experiments to research the issue:
I'm an idiot, so mod me up !
BTW. Isn't "photonic laser" a bit redundant - the "l" in laser stands for "light", after all ?
Re:acceleration? (Score:5, Insightful)
Remember, there's a big gap between "likely untrue" and "always untrue." When someone can look at their own statement, realize what it implies about their capacities, and then confidently declare "I am an idiot," they are displaying insight that is well above average, and certainly deserving of mod points.
I, for one, welcome our new self-insight-possessing commenters.
Re:acceleration? (Score:1, Insightful)
Let's put this into perspective for people, shall we? If this laser has enough thrust to accelerate the ship at 1G, then it has enough thrust to hover the ship off the ground at the earth's surface.
Imagine, if you will, going to the demonstration for this laser thruster and the laser is so powerful it picks itself up off the ground and hovers a foot in the air just for the sheer mass of the photons it is emitting.
Now that you have seen such a thing in your (now blind) mind's eye, do you honestly think that it is anywhere near possible in the near future?
As long as we are making grand claims about what a laser 'might' do if it were 'scaled up', why don't we get nuts and say earth to mars in an hour, provided we can scale it up even more, and invent inertial dampers while we're at it?
What's in a name? (Score:3, Insightful)
Re:acceleration? (Score:3, Insightful)
You are taking in consideration that the ship wouldn't go from Earth to Mars in a straight line, right?
Oopsy Daisy!
Re:acceleration? (Score:1, Insightful)
Buckaroo? (Score:4, Insightful)
Dr. Bae of the Bae Institute? Seriously?
I went to the Bae Institute's site [baeinstitute.com] and found that it is "an independent space and medical research center."
Physics and space science: check.
Institute named after its physicist founder: check.
Medical stuff: check. Dr. Banzai, of course, in addition to being a great physicist, is also a top neurosurgeon. At the Bae Institute site, it says the Institute's medical technologies can be used, among other things, for treating "brain and spinal cord surgeries."
If Dr. Bae is also the leader of a rock band and says things like "wherever you go, there you are," I'll be surprised if we don't see a wave of stories submitted very soon, all by people named named John, saying that Dr. Bae's research cannot be trusted. I expect these submissions to cite the work of another physicist, Dr. Emilio Lizardo.
Laffa while you can, Monkey Boy!
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