mordant wit

The US military is considering testing the principle behind a type of space drive which holds the promise of reaching Mars in just three hours. The problem is, as New Scientist explains, it's entirely theoretical and many physicists admit they don't understand the science behind it.

Nonetheless, the so-called "hyperdrive" concept won last year's American Institute of Aeronautics & Astronautics award for the best nuclear and future flight paper. Among its defenders is aerospace engineer Pavlos Mikellides, from the Arizona State University in Tempe. Mikellides, who reviewed the winning paper, said: "Even though such features have been explored before, this particular approach is quite unique."

The basic concept is this: according to the paper's authors - Jochem Häuser, a physicist and professor of computer science at the University of Applied Sciences in Salzgitter and Walter Dröscher, a retired Austrian patent officer - if you put a huge rotating ring above a superconducting coil and pump enough current through the coil, the resulting large magnetic field will "reduce the gravitational pull on the ring to the point where it floats free".