This week: efficient ionic wind engines, NASA’s “lassoing” asteroids challenge, and cheap computers on a chip: the Raspberry Pi
Science fairs since the 1960s have had their share of “ionic wind craft” – balsa wood creations that use electrohydrodynamics, or electrically produced thrust – to lift and move to the delight of teachers and kids. But scientists at MIT have discovered that the efficiency of this technique at producing low-level thrust is greater than 110 times than Jet engines, and are working on scaling up the design for use in ultralight craft. The ionic wind devices work by creating ionically charged air that pushes against other air molecules, creating thrust without “chopping” the air, as in propeller and jet designs. The biggest problem is the high voltages required – perhaps in the range of gigavolts for aircraft.
Cowboys in space may not be the first image that comes to mind for NASA, but a new proposal may be much closer to that reality. NASA plans to send a robotic spaceship to “lasso” an asteroid and bring it close enough for an Orion spacecraft – the new replacement for the Shuttle – to rendezvous with it and allow astronauts to practice spacewalk exploration. If this plan is implemented, it would be the first time humans had manipulated a space object on such a grand scale, and may prove the combination of human and robotic space travel is viable. For those worried about disaster-movie like collisions… the asteroid candidates are all in the 25-foot range, smaller than the space rocks that struck Russia last year.
In the 1970s, early microcomputers were sold as kits to build – and both Steve Jobs and Bill Gates got their start by constructing kits for others to use. Through the rise of the desktop PC and notebook, computers have gotten more and more complicated, with fewer people working to understand the basics of computer design and programming. To encourage more kids and adults to get involved with computer design, scientists at the University of Cambridge designed the Raspberry Pi, a new microcomputer with the processing power of desktop units from 15 years ago – and sold for less than forty dollars. The Raspberry Pi is a stripped down computer platform – it arrives without mice, keyboards, monitors, or even a case – but it does provide opportunities for tinkering with computers in a way that has long been lost. Projects have sprouted up across the internet for uses or builds of the Raspberry Pi, and its open-source nature encourages new projects all the time.
