If you really could see Han shoot first, it would look a bit like this.
Let’s get this out of the way: Though the laser gun is a staple of science fiction, the stuff coming out of in Star Wars’ blasters were neither lasers nor plasma. But since the only pulses we can reliably fire in our galaxy are lasers, researchers at the Laser Centre of the Institute of Physical Chemistry of the Polish Academy of Sciences and the Faculty of Physics (say it five times fast) have decided to visualize it.
But to see anything, the team had to use a bit of trickery — we don’t have cameras that reliably run at 1,000,000,000 FPS.
Laser pulses are unimaginably quick. Coming and going in a millionth of a billionth of a second, they simply move too fast to be accurately recorded by any camera, especially the human eye (that’s why real space battles would look so different). So to capture the pulses from the laser the team constructed, they synced a camera with them — each firing about ten times per second. The result is what looks like one single pulse moving down the hallway, but in reality each frame of the movie is a different pulse, slightly further along than the last.
You can watch the full demonstration (complete with uber-creepy after images of the researchers walking around the beam) below:
The laser bolts move through the air as you might expect, but why do they suddenly get brighter?
Well, the laser the team constructed is crazy-powerful — like 10 trillion watts powerful. The average lightning strike puts out maybe one-tenth of that. Pulses this strong immediately ionize the air around them like lightning does too. That is, the high-energy particles in the laser jiggle the electrons of the gas in the air, releasing heat and light.
A light pulse fired from the 10 TW laser, dispersing into water vapor. The blue glow is laser light. The source of the other colors is mainly plasma arising from ionized matter, located in the air in the path of the laser pulse.
Finding out what a Star Wars-style blaster bolt would really look like — even the technique of capturing a laser pulse on camera — isn’t the innovation here. According to the team, the laser they constructed for this demonstration was powerful enough to create white light over the long distances it was traveling. The light was white because the high-powered pulses were turning enough gas into plasma to generate many wavelengths of light, which all combine as white light. Having all these wavelengths to work with will give researchers the ability to detect different properties of our atmosphere at some distance, making remote measuring of atmospheric pollutants easier, for example.
Oh, and just for fun I sped up the video so it looks like lasers firing down the Death Star trenches, because science:
IMAGES: IPC PAS, Grzegorz Krzyżewski