Read A Tall Tail for Free Online

 
    This is true, I swear:
    I was in Orlando in October, staying in one of those big, bland conference hotels. DARPA, the Pentagon department tasked with nurturing Mad Science in all its most speculative forms, had decided to throw a brainstorming conference on the 100 Year Starship—a mind-meld to try and figure out what research they’d have to conduct in order to have a hope of beginning to build a starship some time in the twenty-second century. And for no reason I clearly understood, they decided to fly in a bunch of SF authors from all over the world. I’m not sure why the Pentagon might want a starship, but I was glad someone was paying for me to go to Orlando and kibitz on their conference, and I was happy to bloviate about such things from a hard SF point of view.
    The 100YSS conference exceeded all my expectations—and everyone else’s. But the sheer amount of information on tap made the experience feel a bit like trying to drink from a fire hose. It turns out there’s a lot we don’t know about how to build a starship, but also a lot that we do know, and this was the mother of all networking opportunities for folks with an interest in the field.
    Like all networking sessions, a lot of the interesting stuff happens among small groups by the poolside bar, or over a dinner table in a nearby restaurant. You get talking to some interesting-sounding folks who ply you with beer, and the next thing you know you discover you’ve been drafted into some kind of DARPA-funded think tank, or wake up with a hangover in a North Korean labour camp, doomed to spend the next two years coaching the Great Leader’s son through writing the Nobel Prize–winning SF novel that daddy expects him to produce.
    Luckily that’s never happened to me, but I have had an eye-opening experience or two. Like the chat I had on Sunday evening by the swimming pool.
    The Orlando conference center where they held the 100 Year Starship event had a resort-grade outdoor water attraction. Not only were there hot tubs and a regular swimming pool and a water slide, this hotel had an artificial river about a quarter of a mile long, down which you could drift along on a truck tire, propelled by aquajets and drenched by fountains. On a muggy October evening, after a long day of listening to talks about liquid indium ion drives and aneutronic boron fusion reactors, this was exactly the right place to hang out if you wanted to bump into inebriated floating rocket scientists. Like Greg Benford’s twin brother, Jim.
    You probably know Greg Benford best as a physicist and hard SF writer, one of the “Killer B’s” who dominated the field in the 1980s and who is still actively writing novels and research papers. But you might not be aware that Greg has an identical twin, or that his sibling Jim is a card-carrying rocket scientist. Back in 2011, Jim was doing impressive things with microwave sails, and Greg was talking up the applications of a lot of recently declassified Russian research into nuclear thermal rockets: “They built this underground test complex near Semipalatinsk, so that they could capture the exhaust. And then they ran their motor for nearly five hundred hours. That’s about a thousand times longer than Project NERVA managed, in total—in one burn! It’s safe, and it’s reliable, and it’s the best way of getting to the outer planets.” His tire spun slowly round as he drifted under one of the fountains, and because we were orbiting near opposite sides of the artificial river, our paths diverged. Intrigued, I paddled to catch up.
    â€œDon’t you think launching a nuclear reactor might be a bit problematic?” I asked, as I closed to within hailing distance. “I mean, the antinuclear protests when Cassini launched…”
    Jim waved dismissively. “It’s safe as houses,” he assured me. “You’re looking for safety, right? Nuclear