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Industrial lasers are now so powerful they are thinking of replacing conventional drillbits for oil drilling. They do this by vapourising the rock.
Put that laser onboard a satellite and launch your probe from the parent laser satellite. ...Wait a little bit... Then blast he hell out of your deep
space probe with the laser !
As long as the probe faces away, the laser will impact within an area designed to be used up as a vapourised cloud of particles. - whatever material works best at this; and thereby provide forward propulsion.
Behind this block would be mirrored aluminium plates to prevent total destruction when this block is used up.
This laser cannon could be re-used to launch many probes just like lining up golfballs to tee off.
a string of 10 or so could act as deep space relays for radio or radiation comunication signals.
If these probes trailed a fine wire behind them, would it loose enough electrons to generate power for itself?
Lightcraft Technologies
http://www.lightcra...com/technology.html
These guys seem to think they can do it from earth. [wagster, Jan 28 2006]
Breakthrough Starshot
https://en.wikipedi...eakthrough_Starshot
They're planning something similar for interstellar probes. But their claimed numbers make no sense to me. [notexactly, Oct 02 2017]
[link]
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This idea has already been used (unsuccessfully) for launching satellites from earth. A huuuuge ground based laser (pulsed) was focussed onto a parabolic mirror mounted underneath a 1kg dummy payload. The heat was sufficient to explode the air under the mirror providing upward thrust. It went up, but not very far, I'll see if I can link. |
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Bun for realising that this concept might work better from in space. |
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[wags]The vehicle resembled a chromium-plated dog bowl - it had to be spin with compressed air before launch, and managed an altitude of a few tens of feet with a multi-kilowatt CO2 laser.
Laser-powered space sails are mentioned in "The mote in God's eye".
For serious reaction-powered space vehicles, google "Project Orion" |
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This isn't really the same as the laser powered jet engine the commentators mentioned as this works in a vacuum. And for that reason I think it has a major problem, wouldn't the engine exhaust interfere with the incoming laser? |
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The biggest problem is divergence of the beam. Next is the relatively low specific impulse, probably less than using a rocket, and a hundred times less than an ion engine. |
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//wouldn't the engine exhaust interfere with the incoming laser?//
Not if you pulse the laser. That's the way it works in wagster's link, which is supposed to work in the atmosphere. So the propellant is superheated air, and divergence is less of a problem because of the short distances involved. |
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Sure it would - if we're assuming the trajectory is directly away from the laser. [AbsintheWithoutLeave] (and Niven and others) have it right - why resort to reaction mass at all? Just use a diffuse beam like your personal solar wind. Divergence isn't an issue until you start missing the sail. |
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If we have to boost the laser into space anyway, why not use something more efficient and attach it directly to the probe? |
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