Are we any closer to the dream of interstellar travel? Some say yes, but with caveats. Emeritus Executive Director of the Planetary Society, Louis Friedman, believes it will still be many, many years before humans go to the stars, if ever. But he has great hope for our robotic explorers and ambassadors. I got Lou on a Skype connection for Planetary Radio as he was attending last week's 100-Year Starship Symposium in Houston. Lou believes more than ever that the only practical way to cross lightyears is the solar sail.
Science fiction author Gregory Benford take a wider view. The UC Irvine physicist and his brother, James Benford, have conducted successful tests of microwave propulsion, a twist on solar sail technology. The Benfords have also just published a fascinating collection of essays and stories that capture both the current thinking about--and the wonder of--the starship. I had a blast reading "Starship Century--Toward the Grandest Horizon" in preparation for my live conversation with Greg Benford at Southern California Public Radio on Wednesday, September 25. It's part of my NEXT series in SCPR's Crawford Family Forum. (You can watch the live show at 7pm Pacific. The on demand archive will be available on the same page soon after the event.)
I highly recommend the book. Some of our finest science fiction writers contributed work, and there are science-based speculations that floored me! Just one example is the close of John Cramer's essay about exotic technologies. Start with the assumption (a very big one) that we can create or locate a small wormhole in space. Cramer proposes placing just one end of that conduit in the Large Hadron Collider, spinning it up to nearly the speed of light, and flinging it toward a nearby star. Still with me? It gets even more outlandish. Cramer says the math and relativity tell us that we would have created a time machine, allowing for the transmission of data, and possibly even matter, between Earth and the other system in DAYS, not years.
Okay, most of the book is much more, uh, Earthbound, and it doesn't shy away from describing the tremendous challenges of interstellar travel. Paul Davies worries that we won't know which of the millions of strains of essential microbes that infest our bodies and our environments must be brought along on the trip.
Don't expect to buy your ticket for Proxima Centauri next week or even in 100 years, but thinking about an age in which such travel is possible is ample reward for now. Ad astra, folks!