Photon torpedoes vs. nukes: Scientists agree — Star Trek wins

A while back we wondered who would win in a battle between Star Trek's USS Enterprise and the Battlestar Galactica. In the comparison we gave Galactica's nukes an edge over Enterprise's photon torpedoes based on how the weapons are depicted in the movies and TV. Our commenters promptly began dissecting our admittedly cursory logic to figure out which weapon technology which would win in the "real" world, which we thought was a pretty good question.

To find some semblance of an actual answer, we turned to two scientists: Dr. Lawrence M. Krauss, a professor at Arizona State University and author of The Physics of Star Trek, and science-fiction author Dr. Geoffrey Landis, a former professor of astronautics at MIT. Hit the jump for their take on whose boom is best.

"Antimatter weapons are always more effective, in that they give the biggest bang for the buck," says Krauss. "They turn 100% of the matter energy to radiation, and thus extract all the energy possible for an explosion. Nuclear fusion, on the other hand, extracts about 1% of the available energy."

Landis agrees that an antimatter weapon would give "more kaboom for the kilogram," but that it's irrelevant for most practical purposes.

"In terms of weapon effectiveness, though, it's not relevant — an 'ordinary' nuclear weapon is already quite capable of destroying a city. It doesn't really matter which you use — either one is going to have quite an effect."

Defending against either type of weapon would be a huge challenge. Short of some kind of "magical" technology like energy screens, says Landis, any spacecraft would be toast if it were hit.

"In Star Trek they have 'deflector shields' that seem to be pretty good at keeping the nasty stuff like photon torpedoes away," he says. "At least, right up to the point where the shields are overloaded and Scotty calls up from engineering to say 'the engines can't take much more.' Which seems to happen once per episode, so maybe the shields aren't so good after all."

Weapon design is an issue as well. Krauss has a problem with Star Trek's relatively small, coffin-size photon torpedoes. He says this isn't realistic, given that producing and storing antimatter both require huge amounts of energy. "Right now, it would cost many thousands of times the gross national product of the U.S. to produce enough antimatter to light up a light bulb. Also, you would have to confine it magnetically, otherwise it would annihilate with the walls of the container. This is also very energy intensive."

Landis recognizes the challenges, though he points out that since you'd only need a tiny bit of antimatter to create an effective weapon, a photon torpedo could theoretically be smaller a nuke.

"If you need, say, a 100-kilogram superconducting magnet to create the fields needed to suspend a 1-gram sphere of antihydrogen, your photon torpedo's going to be a little bigger than a beach ball."

One thing the two scientists agree on is who would win in a ship-to-ship battle between the Galactica and the Enterprise. Landis says, "Overall, I still think I'd bet on the Enterprise. If nothing else works, you can count on Captain Kirk to do something illogical to save the day!"

Krauss concludes simply: "Enterprise — it always wins."