"Les Johnson is a NASA physicist, manager, author, husband and father. By day, he serves as the Deputy Manager for the Advanced Concepts Office at the NASA George C. Marshall Space Flight Center in Huntsville, Alabama. In his spare time he writes popular science books and articles, reads science fiction, and fulfills the role of husband and father to his two children."
So I gladly accepted this opportunity to interview a NASA author! The following is an account of this interview:
Visual Astronomy: How many years do you think it will be until there is a viable (maybe manned) interplanetary mission using solar sails or other sailcraft?
Johnson: Unfortunately, none of the world's space agencies are making significant investments in solar sails. With the exception of the privately funded Planetary Society, we are not aware of any "active" efforts to fly solar sails. That said, it will likely be decades before we see them performing missions in deep space -- and these will certainly be robotic. The technology required for manned missions is currently beyond what we know how to engineer.
Visual Astronomy: Do you think that the first sailcraft to leave Earth for the stars will be manned or robotic?
Johnson: I believe the first interstellar sailcraft will be robotic. Even with their immense size, they will be relatively easy to build compared to those required to support humans on such a long journey.
Visual Astronomy: Do you think that going forward in the next few decades, that solar sailcraft will be politically viable, and that funding for such an experimental craft will exist?
Johnson: Yes. They will be built and used because there are some missions that may only be accomplished using solar sails. There are others that will be less expensive to fly if a solar sail is the main propulsion system.
Visual Astronomy: What are some applications of the solar sail that could be useful in low Earth orbit?
Johnson: None. There is too much atmosphere in Low Earth Orbit (LEO). LEO is not a true vacuum and the drag forces resulting from the sail interacting with this atmosphere, however diffuse, will be greater than the propulsive thrust derived from sunlight.
Visual Astronomy: Do you think that someday sailcraft will be affordable enough that a civilian hobbyist or traveler could purchase one?
Johnson: Millionaires are buying rides to space from the Russians and Virgin Galactic is selling seats for their suborbital flights quite handily. Yes, a wealthy hobbyist could purchase one and fly it today.
Visual Astronomy: If you had a personal solar sailcraft, what would you name it and where would you go with it?
Johnson: I have to answer that by giving 3 timeframes: currently, in 25-50 years, and in 100 years. Currently: I would buy a small robotic solar sail, similar to the NASA NanoSail-D, and send it to deep space to show that world that it can be done. 25 - 50 Years: I would buy a larger robotic solar sail and ask that my ashes be flown into deep space upon my death. 100 Years: I would ask the my investment trust fund pay for the first interstellar solar sail -- Proxima Centauri or Bust!