The current rage in space technology is building very small satellites, tiny little guys that can do big work/research while weighing anywhere from 1 to 10 kg. The thing is, unless they’re carrying human beings and all of their attendant life-support/comfort technologies or doing something necessarily bulky, there isn’t a huge need for satellites to be very big at all. And they’re a lot of things nanosatellites can do that others can’t (or are very overqualified to do), like inspect other satellites, team up with their nanosatellite buds to perform distributed tasks (in satellite swarms), Earth observation and remote sensing (earthquake prediction, GPS, weather, and well beyond), monitoring space radiation and Earth’s geo-magnetic field, collecting space-borne samples for research, and collecting growing mounds of pesky space junk.Nanosatellites are also dirt-cheap, relatively speaking. A more common satellite can reach into the hundreds of millions of dollars for a launch; a nanosatellite can cost as little as a half-million dollars. Just think: your very own satellite for the cost of a single-bedroom Williamsburg condo. The catch, however, is getting the things around once they’re in space; propulsion technology, still generally based on combustion, does not scale down very well to the “nano” realm. Most nano-satellites become fairly limited in orbit.This is poised to change in the very near future. The Swiss MIT-like university École Polytechnique Fédérale de Lausanne has developed a new satellite thruster, weighing just 200 grams, that can get a spacecraft to the moon on about a tenth of a liter of fuel. Moreover, it doesn’t actually burn fuel at all, but emits it in tiny streams of “ionic” liquid called EMI-BF4, a solvent and electrolyte, from dense arrays of tiny nozzles, as much as 1,000 per square centimeter. Basically, it works by accelerating positively and negatively charged ions via an electric field (alternating itself between positive and negative). The electricity, a fairly large quantity of it, comes from solar cells.The new propulsion device will find itself first on a satellite called CleanSpace One, tasked with collecting orbital space junk and sending it into Earth’s atmosphere to get burned up. It’s a fun thought — this tiny little spaceship racing around the planet at tens of thousands of kilometers-per-hour grabbing scrap and flinging it toward Earth. Like a space-bound Wall-E. Cute.The rocket can get a spacecraft up to 42,000 kilometers-per-hour, accelerating at the breakneck rate of a single tenth of a millimeter per square second (so, 77 hours to get to a highway speed of 100 km/hour). “We calculated that in order to reach lunar orbit, a 1-kg nanosatellite with our motor would travel for about six months and consume 100 milliliters of fuel,” says EPFL’s Muriel Richard. “At the moment, nanosatellites are stuck in their orbits,” adds Herbert Shea, also of EPFL, in a press release. “Our goal is to set them free.”Reach this writer at michaelb@motherboard.tv.
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