Slashdot Mirror
NASA Flies First Laser-powered Aircraft
unassimilatible writes "NASA has successfully tested a small-scale aircraft that flies solely by means of propulsive power delivered by an invisible, ground-based laser. How far away can in-flight IP/LASER broadband be?"
How far off can space death rays be is the real question
or something like it:
It used microwaves instead of "invisible lasers" (IR? i havent RTFA yet) but same end result, no?
Newsie, Moderator, www.tauniverse.com
One of the hallmarks of classic science fiction, Larry Niven & Jerry Pournelles' "The Mote In Gods Eye", proposes this very thing. The opening sections of the book are based upon on premise: lacking true FTL travel, an alien race reaches a human colony by building humungous lasers in their asteroid belt and planet surface, and using them to propel a light sail armed interstellar craft between stars. Good book all around, and it's cool to see decent Science Fiction become more than just speculative drivel (it's one of my favourite books).
This is the technology they want to use to power the space elevator.
If they are using laser beams to power a generator in the plane, why don't they use this to solve our energy distribution problem? In blackouts, just beam power to cities by laser.
How far away can in-flight IP/LASER broadband be?
Let's hope it's very, very far off. A laser beam pointing to/from a commercial aircraft is essentially a giant pointer, constantly updated, announcing the precise position of the plane. It should not be difficult at all to build a guidance system that follows the laser and delivers a payload to the plane just as a line climber follows a kite string to a kite. Said payload is not likely to be an emergency delivery of peanuts and soda.
I can see it now:
"Homeless celebrate as pre-cooked pigeons fall from sky near airport"
Slashdot is like Playboy: I read it for the articles
When was the last time you saw an invisible laser.. lasers are in the visible light spectrum
I'm not a physicist, but I've seen lots of inivisble lasers (okay, not the beam itself, but you know...). Lasers in both the infrared and ultraviolet regions are commonplace. Google for "infrared laser" or "ultraviolet laser" and you'll find many, many examples of each.
I suppose you could make some sort of argument that the L in LASER if for "light," and that IR and UV somehow aren't light because we can't see them. But insects and perhaps some animals can see in those regions, so it'd be a difficult position to defend. Both IR and UV are called "light" in general use. Additionally, there's no significant physical difference between a visible light laser and a UV or IR laser. And scientists now use the term "laser" even where most people would agree that the electromagnetic energy in question falls outside the part of the spectrum that we tend to think of as "light," e.g. x-ray lasers and microwave lasers.
I first read about this sort of thing back in the 1970s. Proposals back then focused on constructing huge satellites (think 5 miles by 5 miles or 10 KM by 10 KM) in geosynchronous orbit. Energy would be beamed to earth via microwaves or lasers.
Planes could be powered via laser pointed at various reception devices (photovoltaic, steam generators, etc.).
Clouds would not be a major problem. Just pick a frequency that penetrated the clouds fairly easily. Or, in the case of airplanes, fly above the clouds.
For lots more information, just Google "Space Solar Power".
"Beer is proof God loves us and wants us to be happy." -- B. Franklin
This is cool but I like China's space program better...they are going to be doing manned exploration of S P A C E.
National Aeronautics and Space Administration