Subscription Center
Aug 25, 2008 | 2
The Pentagon's hope of having a squadron of unmanned aerial vehicles (UAV) capable of staying in the air and performing surveillance for years rather than hours recently took a small step forward. Working with U.K.-based idea factory QinetiQ Group PLC, researchers from the U.S. Defense Advanced Research Project Agency (DARPA) managed to keep the solar-powered Zephyr high-altitude, long-endurance aircraft in the air over the Arizona desert for 82 hours 37 minutes, beating the 54-hour flight completed last year by an earlier version of the aircraft, the company reports on its Web site.
Launched by hand, the 66-pound (30-kilogram) Zephyr is an ultra-lightweight carbon-fiber aircraft that during the day flies on solar power generated by silicon solar arrays no thicker than sheets of paper that cover the aircraft's wings. At night it's powered by SION Power Inc.'s rechargeable lithium-sulfur batteries (recharged during the day using solar power), according to the company.
See what we're tweeting about
BecCrew I have no idea what this means but I love it so much http://t.co/NA5WMMApWS
DNLee5 #DispatchesDNLee: Non-target capture Marsh Mongoose: http://t.co/h6iOKMW63v via @YouTube
Horganism Ahab to severed whale head: O head! thou hast seen enough to split the planets and make an infidel of Abraham and not one syllable is thine!
Deadline: Jun 29 2013
Reward: $7,000 USD
The Seeker for this Challenge desires proposals for chemical methods that could rapidly degrade a dilute aqueous solution
Deadline: Aug 31 2013
Reward: $100,000 USD
The Geoffrey Beene Foundation Alzheimer’s Initiative (GBFAI) is launching the 2013 Geoffrey Beene Global NeuroDiscovery Challenge whose
Powered By: 
YES! Send me a free issue of Scientific American with no obligation to continue the subscription. If I like it, I will be billed for the one-year subscription.
