Original URL: http://www.theregister.co.uk/2014/05/03/laser_deflector_shields_are_possible_with_todays_tech_but_with_a_small_problem/

Laser deflector shields possible with today's tech – but there's one small problem

You'll need to use the Force when shields are up

By Iain Thomson

Posted in Science, 3rd May 2014 01:07 GMT

Vid A new paper from the University of Leicester claims that it's technically possible to build shields around a spacecraft to protect it from laser fire using available technology, but with the somewhat troubling side effect of leaving the pilot unable to see where he or she is going.

The research, published [PDF] in the peer-reviewed Journal of Special Physics Topics, posits that an effective shield could be built using a ball of super-hot plasma that would surround the spacecraft to protect it from laser fire. The denser the plasma, the more effective it would be at deflection.

The plasma shield is a reality today, although it comes not from mankind's own designs but from natural development – or a deity, depending on your belief system.

"The Earth's atmosphere is made up of several distinct layers, one of which is the ionosphere. The ionosphere is plasma, and extends from roughly 50km above the surface of the Earth to the edge of space," said coauthor Alexander Toohie.

"Just like the plasma described in our paper, it reflects certain frequencies of electromagnetic radiation, in this case radio frequencies. Radio communications and RADAR can be beamed upwards toward the sky where it will be reflected back down toward the Earth.

The huge disadvantage to the shields is that not only would they screen off light-based weaponry from coming in, but they would also not allow light to reach the pilot. This is somewhat of a disadvantage in a combat situation, but the authors suggest an ultra-violet camera may be able to see out.

The other drawback is physical. Any spaceship carrying the shield would need a massive magnetic array to contain the plasma bubble, not to mention a power source capable of maintaining it.

Although the three fourth-year physics students who authored the paper – entitled "Shields Up! The Physics of Star Wars" – acknowledge that we're not going to see such well-equipped spaceship any time soon, the work does have practical applications.

"Another possible application of this principle may be for trapping radiation inside a shell of plasma rather than excluding it" said Toohie. "This may be useful for applications that require incredibly high temperature environments, such as experimental fusion reactors." ®