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Toward a High-Velocity Astronomyby Paul Gilsteron May 15, 2019 Couple the beam from a 100 gigawatt laser with a single-layer lightsail and remarkable things can happen. As envisioned by scientists working with Breakthrough Starshot, a highly reflective sail made incredibly thin — perhaps formed out of graphene and no thicker than a single molecule — could attain speeds of 20 percent of c. That’s good enough to carry a gram-scale payload to the nearest stars, the Alpha Centauri triple system, with a cruise time of 20 years, for a flyby followed by an agonizingly slow but eventually complete data return....

Beam-Riding and Sail Stability by Paul Gilster on June 23, 2017 Breakthrough Starshot, the ambitious 30-year plan for launching small interstellar craft to a nearby star, depends critically on the sails that will ride a laser beam to 20 percent of lightspeed. In the essay below, James Benford takes a hard look at where we are now in the matter of sail stability, a subject he and brother Gregory have analyzed in their laboratory work. But as Jim points out, there is a great deal we still don’t know, emphasizing the need for a dedicated test facility in which deep...

Starshot: Concept and Execution by Paul Gilster on April 22, 2016 Because I get irritable when I don't get my walking in every day, I made sure when I arrived in Palo Alto to cram as much as I could into the day before Breakthrough Discuss began. That meant heading out from the hotel just after noon and putting in about five miles. Palo Alto is a very walkable place and I found myself ambling up and down shady streets past gardens bright with spring flowers. We had superb weather for the entire conference, but naturally when things got going,...