Skip to comments.Thruster May Shorten Mars Trip (from six months to a week!)
Posted on 09/10/2007 11:31:01 AM PDT by LibWhacker
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.
The demonstration produced a photon thrust of 35 µN and is scalable to achieve much greater thrust for future space missions, the institute said. Applications include highly precise satellite formation flying configurations for building large synthetic apertures in space for earth or space observation, precision contaminant-free spacecraft docking operations, and propelling spacecraft to unprecedented speeds -- faster than 100 km/sec.
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 founded the institute to develop space technologies and has pursued concepts such as photon, antimatter and fusion propulsion for more than 20 years at SRI International, Brookhaven National Lab and the Air Force Research Lab. He has a PhD in atomic and nuclear physics from UC Berkeley.
Several aerospace organizations have expressed interest in collaborating with the institute to further develop and integrate PLT into civilian, military and commercial space systems, Bae said, and he has recently been invited to present his work by NASA, JPL, DARPA and the Air Force Research Laboratory (AFRL).
Franklin Mead, a senior aerospace engineer at AFRL, said in a Bae Institute statement that the PLT demonstration and measurement of photon thrust is "pretty incredible. I dont think anyone has done this before. It has generated a lot of interest."
The institute said Bae paper, Photonic Laser Propulsion: Proof-of-Concept Demonstration, was recently accepted for publication this year in the American Institute of Aeronautics and Astronautics' Journal of Spacecraft and Rockets. It documents how he overcame the inherent inefficiencies of traditional photon thrusters in generating thrust by amplification with the use of an innovative optical cavity concept.
"For decades, rocket scientists have tried to overcome the inefficiency of photon thrusters by amplification based on optical cavities separated from laser sources, but failed," the institute said. "In contrast, Baes PLT (patent pending) places the laser medium within a resonant optical cavity between two platforms to produce a very stable and reliable thrust that is unaffected by mirror movement and vibration -- ideal for spacecraft control or propulsion."
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.
The PLT research was partially funded by NIAC (NASA Institute of Advanced Concepts) as part of a spacecraft formation flight concept grant.
Does this mean I can go home now?
I wonder if you could make a torpedo out of that thing?
Sorry, I had to say it.
35 µN? That ain’t a lot of cookies....................
So, after testing and all, it may be ready for use in like the year 29,4701.
How many G's would you be pulling?
1. A pebble deflector
2. A lot of braking power.
The micromotor could get a micropayload to Mars in a week. If they bolt a hundred million together they could get a one pound payload to Mars in a week.
But I have a lot of doubts about it myself. We see too many of these too-good-to-be-true scams.
But... IF it's real... OH, BOY!
I googled a few articles about this, and I still don’t get it - if photons have no mass, how can they provide acceleration in a vacuum?
Photons carry momentum.
And, is that a ‘transit’ using steady acceleration for 7 days — in which case you blast by Mars doing a gazillion mph — or is it 3.5 days to mid-point, at which time you do a 180 and start decelerating (presumably maintaining a constant G load throughout?)
Anybody know how long a human can function under sustained multiple g-loads?
Better phone home first...
If it was built by using “off the shelf parts” then it’s not patentable, IIRC.......
They now need to invent photonic brakes..........
He’s going to have to scale up the power considerably. I think RightWhale has it right... If my back of the napkin calculations are right, and If he can scale it up by a billion-fold (i.e., to 35,000 Newtons), a million kilogram ship (i.e., one of respectable size), starting at an initial velocity of zero, would travel about one kilometer towards Mars in a week’s time. LOL, not too good. So he’s going to have to scale up by a factor on the order of quadrillions or so.
Gotta love that name.
That’s the same question I had when NASA said they wanted to test a Scramjet for space propulsion. They’ll need to carry a lot of air on board.
No, they kinda kicked me off, so I want to surprise them.
Picture how difficult it is to swerve around objects on the highway at high rates of speed. Now apply that to space only you are moving at much faster rate of speed. Even a tiny piece of space junk the size of a marble can be lethal to a spacecraft moving at a very high rate of speed.
So unless we can develop some kind of sophisticated radar that can allow our spacecraft to see these objects millions of miles away and automatically make slight corrections in course to avoid these tiny objects or unless we develop an exterior to the spacecraft that is impervious to collisions at high rates of speed, we are going to continue to be limited in how fast we can go in space.
What we really need to focus on is teleportation.
An effective photon thruster would also make an effective raygun...
Another possibility I’ve read about: Inducing an artificial “atmosphere” around your ship that extends out hundreds of miles and in which any moderately massive incoming asteroids would burn up. This, perhaps, could be some kind of plasma held in place by a strong magnetic field?
Wow, just like my Corvette! ;-)
1G appears to be sustainable for 90+ years. I think that all sustained acceleration would aim to hold 1G. I think that would provide the said velocity of 100 km/sec in less than 24 hours. Dropping that acceleration to .5G would likely provide a more comfortable trip.
A lower thrust over a longer period would seem to be better.
As long as its not an assault raygun.
2. A lot of braking power.
If the thruster can accelerate it, the same thruster can brake it.
Ping to you. Wonder if it would break any glasses?
This is what shields are for, haven’t you ever seen StarTrek?
Sorta my point. A lot of fuel will have to be accelerated, because it will be needed to de-accelerate.
This is WAY too cool to be true.
Yadda, yadda, yadda.
What’s REALLY important is the carbon signature of this thing. Until we know that, we won’t know how many offsets will be needed...
The bad news is it works just like the flux capaciter and requires 1.26 gigawatts to run.
No, it wouldn't. They said that they would get you there in a week. Nothing about you being in any shape to ever come back. Just keep on accelerating until impact.
In the simple case of a constant force (assuming a constant mass):
x(t) = x_0 + v_0t + 0.5 * a t² (x_0 and v_0 are assumed to be zero)
a = 2*x(halfway)/t² = 2*50e9 m/(3.5 days)² = 1.09 m/s²
This is about 1/9th of a g. If they had the capability to have 1 g of acceleration then the transit time would only be 56 hours (1/3 of a week).
Oh, I should also mention that since power equals force times velocity, it probably wouldn’t be feasible to be able to power the thrusters after the beginning of the trip so the initial forces will have to be much higher.
Err, I mean that the thrusters will have the same power applied, but will lose thrust the faster you go, so your initial thrust has to be much higher than the lower thrust (using the same power) later in the trip (because KE = 1/2 mv² and you have to pay 4 times the energy for every doubling of velocity).
Whatever mass you're kicking out of the back of the vehicle is accelerated relative to the vehicle. No matter how fast the vehicle is going, if the mass-flow-rate and the delta-v is the same, the thrust produced is the same and the energy cost is the same.
Once you go warp, you’ll never look back.
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