The first day of the Interstellar Workshop featured the Starship Century and Breakthrough StarShot groups. On Thursday the Tau Zero Foundation took center stage. The Tau Zero group aren't as wedded to a single goal or mission profile. Instead they've put a lot of effort into identifying key technologies which will benefit any interstellar exploration, and have tried to support research in those directions.
The opening talk was by Marc Millis, chairman of the Tau Zero Foundation, explaining their modus operandi, and discussing some of the motives for interstellar voyaging and how those affect the specific mission plans — if you want to colonize other star systems, you'll have to work on extremely long-duration missions, but if you want bragging rights for the first interstellar probe, you should work on a StarShot-style flyby.
One obvious key technology for any space exploration is launching things off Earth and making use of resources in near-Earth space. So Jonathan Barr of United Launch Alliance gave a talk about their new Vulcan booster and the adaptable ACES upper stage, which could become the workhorse of cislunar space. ULA wants to sell more rockets, so they're trying to come up with ways to increase the number of people in space; the goal is 1,000 humans living and working off-Earth by 2050. Amazingly, Mr. Barr managed to get through the entire presentation without ever uttering the dread syllables "SpaceX."
He was followed by Jeff Greason, the Chairman of the Tau Zero Foundation, formerly with XCOR and now the head of Agile Aerospace. He had an amazing presentation about the possibilities of plasma sails, inspired by research done by John Slough of the University of Washington. With only 10 kilowatts of power, a spacecraft can gnerate a "virtual" magnetic sail to capture the charged particles of the solar wind. In the inner solar system, this allows for some remarkable velocities — up to 400 kilometers per second, which is 20 times faster than the New Horizons probe to Pluto. The chief drawback is that like all sails, the thrust only goes away from the Sun — so you can use a plasma sail to zip over to Mars in a week, but you can't stop when you get there!
But the prospects of a drive allowing such tremendous speeds for a relatively low power requirement and no propellant at all are still incredible, and everyone including Mr. Greason was astonished at how the plasma sail technology has been overlooked.
After a coffee break we saw some presentations about antimatter. Marc Weber of Washington State discussed how to store antiparticles (answer: with great difficulty, that's how). Then Gerald Jackson, late of Fermilab, talked about how to make antimatter in commercial quantities. The current goal is to get production up to 2 grams per year of anti-Carbon; over 8 years that would generate enough to launch a probe to Proxima Centauri.
George Hathaway finished up the batting roster for the morning, with a discussion of all the issues involved in testing "advanced propulsion concepts" — in other words, busting frauds and crackpots. Proper testing of radical new technologies means the testers have to be obsessively methodical, considering and compensating for everything from seismic vibrations to the tides.
After lunch I attended some shorter talks. The first was a presentation about alien life and how unlikely it is that even a life-bearing planet with an oxygen atmosphere would be ready for settlement by interstellar pioneers, simply because of chemical incompatibility.
The second short talk was by Ore Koren, a grad student from the University of Minnesota, who discussed some important issues about minimizing social strife aboard a "generation starship" traveling for centuries.
And finally Dr. Giancarlo Genta spoke about some experiments he and his team had done in creating computer simulations of a spherical laser-sail interstellar probe, to investigate potential issues of stability and dynamics. Professor Genta was careful to point out that his work was still preliminary, more of a proof of concept for the computer modeling than a definitive answer about the ideal sail configuration. That headed off what looked like a scientific slap-fight brewing among partisans of other sail designs.
The rest of the afternoon was devoted to my Working Track group, brainstorming museum-exhibit ideas. At the end of a couple of hours we had covered half a dozen large poster-pad sheets with potential exhibit items. I hope at least some of them eventually get built.
That evening, all of us carpooled over to the U.S. Space and Rocket Center museum for what has to be the most "Huntsville" event possible: Biergarten Night at the Saturn V exhibit. A good-sized crowd gathered to enjoy bratwurst, schnitzels, red cabbage and potato salad, along with some excellent beer — all served up underneath the hanging bulk of the museum's historic Moon rocket.
As a finale to the long day we gathered in the museum auditorium for a lecture by Dr. Andrew Siemion about SETI research, especially the Breakthrough Prize Foundation's "Breakthrough Listen" project he's connected with.
And so to bed. Tomorrow: the final day!
It's October, and that means it's the right time to read about scary monsters — so buy my new ebook Monster Island Tales!