Science Sunday VII: Photonic Propulsion

If you're feeling a bit claustrophobic on our current earth-sphere, I have some good news: high-speed space travel just got a little bit more feasible.

The photon is a strange particle (or wave!) Though it has no mass, it can still impart momentum. When you turn on a light, the photons from it collide with you, and actually physically move you. It is not detectable to our senses, but every time photons hit us, they exert a force upon us. Shine a strong enough flashlight on a ball, and it will roll. This is known as radiation pressure (and FYI light is just a form of radiation.) With a strong source of light, such as the sun, and low gravity and friction, such as in the vacuum of space, radiation pressure is a viable means of transportation. This basic effect is the idea behind solar sails, and has already been used in unmanned spacecraft, such as Mariner 10. But that is all old hat.

It has been theoretically proposed that photons, in the form of lasers, can be amplified so that their thrust is greatly increased. In December of 2006, Dr. Young Bae did just that, by building (and publicly demonstrating) the world's first Photonic Laser Thruster (PLT), which amplifies photonic thrust by a factor of 3,000. Not bad for a proto-type. The demonstration paper will be published in the peer-reviewed journal American Institute of Aeronautics and Astronautics (AIAA), is titled Photonic Laser Propulsion: Proof-of-Concept Demonstration, and will be published later this year. Using several of these photonic thrusters together, spacecraft could achieve speeds of more than 100 km per second. This technology is not far-and-away, it is already present, and is being refined for more efficient use. With current technology, the trip to Mars would take six months. With PLT, it would take one week or less. Given that most of the hazards of interplanetary travel are risky precisely because of the length of the journey (radiation accumulation, bone deterioration, psychological stability), this just doesn't make interplanetary travel more comfortable, it makes it possible. There is still plenty of research and application to be done to be sure, but the deployment of these technologies will now be measured in years rather than generations.

A more practical application of PLT would be to maintain exact satellite formation - by exact, I mean staying within formation to a few nanometers, with the satellites spread out over kilometers. An immediate use of this kind of technology would be to form the next generation of telescope-like devices - satellite formations like this could scour the depths of the universe at many orders of magnitude greater detail than the Hubble telescope - we could detect black holes for the first time, see planets and stars never seen before, and indeed peer into the very origins of the universe. Considering the pictures from Hubble, think of what we could do with several orders of magnitude beyond this:





Of course these satellite formations wouldn't just take pretty pictures; more pragmatically, they would be able to search for rare minerals in asteroids, uncover precise details of our own solar system's planets and moons, and let us prioritize where our other efforts should focus.

And holy $hit, he's also made a lot of progress working on nuclear fusion engines and researching a freakin' matter-antimatter engine. What's next for this guy, an artificial quantum singularity engine?

I think the coolest part of this is that Dr. Bae is not a NASA scientist. He's just a really smart guy who loves to invent things, and started his own institute to do so. On his own, he built his amplified photonic thruster - the first in the world - with regular off-the-shelf products. It is becoming more and more clear that in the future it will be individuals and organizations that will lead the way in space exploration as much as it will be nation-states.

For a lengthy interview with Dr. Bae, check out this podcast of the somewhat quirky Space Show. The interview starts at 5:45.

Thursday TED: V (Theory of Brain and Artificial Intelligence)

This week's TED talk is by Jeff Hawkins, a big mover behind the handheld computing industry, and a neuroscientist to boot. He asks why is it that after studying the brain for so many decades we still don't have a theory of how it really works? Hawkins says the time is ripe for a paradigm shift in understanding the brain, and once that occurs, artificial intelligence will not be much further down the road.

Stumbling Finds II: Video Edition

Normally on Fridays I provide some kind of comedy video. Today I'll provide five short videos I Stumbled Upon, some funny, some just bizarre. Here are my top five picks for this week:

This is freakin' incredible! By building a semi-rigid bodysuit of 30+ wheels, Rollerman can roll at high speeds on any flat surface in any body position! His top speed so far is 61 mph. You have no idea how much I want one of these; probably even more than a jet-rocket backpack and even more than a flying motorcycle. It's probably best that I don't have one. I would wear it all the time - late to class? I'll just roll down the hallway and into the classroom at high speed! About to miss my plane? I'll just roll down the mile-long airport terminal, weaving between travellers and suitcases at 60 mph! Sigh... one can dream...



Ever play Minesweeper? Did you know they are making it into a movie?



Ever wonder what would happen if you filled a swimming pool with a non-Newtonian fluid and then went for a swim? Well... it's time to find out!



The UK was the birthplace of the railroad - the good side of that is the UK was the first country to become 'modern' - the bad part of that is we are stuck with infrastructure that is 200 years old. In France and Asia, trains travel up to 500 kph, (300+ mph) five times faster than in the UK. Wow.


Lastly, a brilliant commercial from Germany. Watch it twice, it's clever stuff.

Thursday TED: II

I have been so impressed with the TED (Technology, Entertainment, Design) presentations, I've decided to share one of the best ones every week. The premise of TED is that each presentation is by an outstanding individual whose ideas are considered profound enough that they are likely to change how the entire world thinks and behaves. Last week we took a look at the amazing Trendalyzer software by statistician-humanitarian Hans Rosling. Check it out if you missed it - it's powerful stuff.

This week we'll take a look at a new software program called Photosynth. This is not just a killer app, it is a whole new paradigm of how we think of computer graphics. You just have to watch it - trust me, your jaw will drop. I recommend you click the button on the lower right side of the video player to maximize the video.







The best part is that before too long Photosynth will be freely available on the web. I can't believe I'm saying this, but Microsoft may be doing something right for a change.

More Open-Source Please!

Nintendo has announced they are opening up the Wii, allowing anyone to create and distribute games for it. This is a very smart move. Fans' collective creativity and enthusiasm will always be more innovative than that of a small group of professional developers (for just about anything.) Innovation comes with risk, but fans only risk losing their time if they make a flop. Developers potentially risk their jobs.

Plus, people like having control over their technology - being locked out (technologically and legally) of a system you paid for does not inspire customer loyalty - I'm looking at you Microsoft, AOL, and RIAA. Treating fans and customers as team members will always win out in the long run over treating them as potential intruders and theives. Hopefully, more will follow Nintendo's success.

Google Maps

Google never ceases to amaze me with how far-and-away more advanced they are than just about every rival. Not only is the free Google Scholar about a bazillion times better and easier to use than the electronic journal service the university pays fortune for, now Google Maps offer a 3-dimensional street level option. Check out the video and be amazed.



One user looked up her own house and was able to zoom into her living room and see her own cat!

And of course, if you have never seen Google Earth (again, free!) you must check it out.





In fact, this blog is created with Google software running on a Google server. That's pretty impressive considering how distrustful I generally am of very large institutions.

"Tea, Earl Grey, Hot!"

Anyone who has watched Star Trek will remember the replicators that could make nearly any object materialize through a simple voice command.

While that is still lightyears away, we're getting much closer than one might think.

A new device can create 3 dimensional objects at home. These objects can be made of plastic, metal, and other materials and can be produced in a matter of minutes. It's like a 3 dimensional printer that can "print" anything you have the schematics for. You could make an action figure of yourself, "print" some new candle holders, or some replacement parts for your washing machine. The way it works is by a large number of very small nozzles that spray the plastic/metal/etc in a heated, liquid state, much like a printer sprays ink. Once a layer of material is cool and solid, a new layer can be sprayed on top of it, and so on, until the full figure is formed. At first this may seem neat, but trivial. When you think about it, it really has the potential to turn the entire manufacturing and retail industries upside down. Who would ever need to buy toys if you can just create them to whatever desing you want? Just download what you want, and go. Break a small piece of your car? "Print" a new one. Want a new set of silverware? Make some instantly! The technology is still young, but will undoubtedly improve very quickly in quality and affordability. In twenty years, I imagine these will be as universal in households as computers or microwaves. File sharing networks will probably carry more design schematics than music files. It would also seem to threaten the jobs of millions of people, especially in economies like China, which is largely based on producing cheap plastic shapes. It may sound hyperbolic, but I think a device like this will have as much impact on our lives as computers themselves.

Original story is from The Guardian.