Today we get into the heart of this interstellar conference, with multiple sessions on propulsion via solar and electric sail, as well as looks at specific mission concepts and robotic applications in deep space. I spent a good part of our bus ride back from Bard castle yesterday talking to Pekka Janhunen, creator of the electric sail concept, about its possible interstellar applications. Pekka does not believe this system, based on electric tethers riding the solar wind, could muster the velocity to go interstellar, but he does see it as a viable candidate for braking into a destination system, and just as important, exploring it. I'm anxious to get the latest on his work and also to look at fusion alternatives, which Claudio Maccone will present now that we've learned that Claudio Bruno can't make it here. As I get ready for the day to start, I'll drop in here some notes from the first day. These are no more than a skeletal outline -- I'll use the conference proceedings when I get...

I had intended to use today's post to talk about yesterday's sessions here in Aosta, but it's going on midnight here, and tomorrow will clearly not afford any opportunities to write. Tuesday turns out to be our sightseeing day. We leave the hotel at 9:00 and head for Verrès, where we visit the Mechatronics Laboratory of the Politecnico di Torino. Then we head up into the mountains, visiting the Bard fortress, with individual visits to the Museum of the Alps. After lunch at what is said to be an excellent restaurant called La Polveriera, we go to an exhibition called 'Verso l'alto, l'ascesa come esperienza del sacro' -- Towards the heights: The ascent as experience of the sacred. Then to dinner at the Hotel Notre Maison, where we are promised traditional Aosta Valley food. Image: The Aosta town hall, where our opening sessions were held. Later, we moved to the Hotel Europe. As for tomorrow, we don't get back to the hotel until midnight. No more today or I'll be late for the bus, but...

What I'll surely remember the most about arriving in Italy is the sight of snow on the Alps as the plane descended out of a cloudy morning sky into Milan. But right after that comes the two hang gliders that soared past an alpine peak as the van that was taking me to Aosta moved north toward the town, the landscape becoming a series of valleys cutting through the steep clefts. The second of the two hang gliders looked for all the world as if it were going to land right on the highway, a daunting thought given how the traffic was moving, but as we rounded a turn I saw that it had caught an updraft and was angling out and away. What a view the pilot must have had. Image: The view from my room at the Hotel Europe in Aosta. It was hot and humid when I took this, but cooled off dramatically during the night. If the air conditioner worked, all would be perfect. Below is a photo from the street in front of the hotel. As you can tell, this is the place to be for a guy who loves mountains the...

Night Flight to Italy I'm off tomorrow night to Italy, specifically to the Sixth IAA Symposium on Realistic Near-Term Advanced Scientific Space Missions. I'll be delivering a talk at the conference and a public lecture in the town of Aosta and, assuming a robust Internet connection, I'll also be sending along news of the conference as it unfolds. I'm looking forward particularly to catching up with Giancarlo Genta, Greg Matloff and wife C Bangs, and Claudio Maccone, and it will be great to touch base again with Les Johnson, whom I haven't seen since we talked at Marshall Space Flight Center in 2003. Superluminal Radio Waves and their Uses An article in the Santa Fe New Mexican discusses the work of John Singleton, a physicist at Los Alamos National Laboratory, who has created a 'polarization synchrotron,' which according to the report pushes radio waves faster than the speed of light. In a paper on this work, Singleton explains that: ...though no superluminal source of...

Is the movement toward ever more sophisticated technology irreversible? If you've studied history, the answer is obviously no. Various speculations arise from this -- Carl Sagan once opined that without the intervening collapse known as the Dark Ages, we might have seen a Greek civilization exploring near-Earth space a thousand years ago. It's also likely that no law prevents another collapse into technological and scientific somnolence, perhaps sparked by war, or disease, or economic catastrophe. This is why I always hedge my bets when asked about timetables for space exploration. How long until we get humans to the outer system? How long until we launch a fast starship? Everyone is in a hurry, but so much depends on whether we keep growing our technology. Nanotechnology, for example, could change everything, but it's one thing to be using molecular assemblers by the end of the century, and quite another to see the fruition of this work stalled for a millennium by external events....

The eruption of Mt. Tambora in Indonesia in 1815 pumped so much sulfur dioxide into the stratosphere that New England farmers found their fields frosted over in July. Climate change, it seems, can be quick and overwhelming, at least on short scales. The eruption of the Mt. Pinatubo in the Philippines in 1991 cooled global temperatures for several years by about half a degree Celsius. Sulfur dioxide works. So how about this: We send a fleet of airships high into the stratosphere, attached to hoses on the ground that pump 10 kilos of sulfur dioxide every second. The airships then spew this mix into the upper atmosphere, a aerosolized pollutant that, turning the skies Blade Runner red, shields the planet from the Sun's heat. Call it geo-engineering, an extreme form of human climate manipulation that is the subject of a recent story in The Atlantic. Into the Anthropocene Writer Graeme Wood notes that our activities have been transforming the planet for centuries now, leading some to dub...

Life Beneath the Ice Three kilometers down in the Greenland ice sheet is what I call an extreme environment. Even so, Penn State researchers have been able to bring a bacterium called Herminiimonas glaciei back to life after a dormancy of 120,000 years in these conditions. The work involved incubating the samples at 2 degrees Celsius for seven months, then at 5 degrees Celsius for a further four and a half, a patient process rewarded by the appearance of the purple-brown bacteria. Ten to fifty times smaller than E. coli, Herminiimonas glaciei evidently used its size to survive in liquid veins amongst the ice crystals. Jennifer Loveland-Curtze describes the find: "These extremely cold environments are the best analogues of possible extraterrestrial habitats. The exceptionally low temperatures can preserve cells and nucleic acids for even millions of years. H. glaciei is one of just a handful of officially described ultra-small species and the only one so far from the Greenland ice...

The bet between Tibor Pacher and myself continues to draw emails, proving that my friend Tibor was right when he saw an interstellar wager as a teaching opportunity. I still maintain that an interstellar mission will not be launched anywhere near as early as 2025, but Tibor does have his advocates, as you can see on the Long Bets site. Moreover, it's been useful to plug in distances and velocities for a 2000-year mission to a place like Proxima Centauri when I speak to audiences about how large the distance between the stars really is. 2000 years is a long time, but we're still talking 650 kilometers per second, and just 20 years to the Oort Cloud! And as a guy who used to build model airplanes back in my youth, first in plastic and then from balsa wood (wonderful memories of working with kits of World War I and II aircraft from Guillow), I can relate to Tibor's latest venture. MiniSpaceWorld is an attempt to create, at a European site still to be determined, a wide-ranging exhibit...