NAUTIL.US | TEXT SETS Going Big: Nuclear Rockets it. “Today the closest technology we have would be Sails may be able to whisk tiny probes to the stars, nuclear pulse,” Matloff says. If anything, most people but they can’t handle a human mission; you’d need would be happy to load up all our nukes on a ship and a microwave beam consuming thousands of times _ be rid of them. more power than the entire world currently generates. Ideally, the bomb blasts would be replaced with con- The best-developed scheme for human space travelis trolled nuclear fusion reactions. That was the approach nuclear pulse propulsion, which the government-fund- suggested by Project Daedalus, a ’70s-era effort to ed Project Orion worked on during the 1950s and ’60s. design a fully equipped robotic interstellar vessel. The When you first hear about it, the scheme sounds biggest problem was that for every ton of payload, unhinged. Load your starship with 300,000 nucle- the ship would have to carry 100 tons of fuel. Such a ar bombs, detonate behemoth would be the one every three sec- size of a battleship, with a onds, and ride the blast length of 200 meters and waves. Though extreme, a mass of 50,000 tons. it works on the same “Tt was just a huge, basic principle as any monstrous machine,” other rocket—namely, ; . says Kelvin Long, an Eng- recoil. Instead of shoot- * lish aerospace engineer ing atoms out the back = ») and co-founder of Project of the rocket, the nucle- \} 7 Icarus, a modem effort ar-pulse system shoots » to update the design. blobs of plasma, such as \) “But what’s happened fireballs of tungsten. LY since then, of course, is You pack a plug of pis * ' microelectronics, minia- tungsten along with a & is turization of technology, nuclear weapon into a Se) nanotechnology. All these metal capsule, fire the NG developments have led capsule out the back of to a rethinking. Do you the ship, and set it off really need these mas- a short distance away. sive structures?” He says In the