Pasadena’s Planetary Society set to launch solar-sailing ‘CubeSat’ nanosatellite
By Adrian Garza 08/07/2014
The Planetary Society recently announced a launch date for its LightSail-1, a “nanosatellite” made of three cubes that are each about the size of a loaf of bread. In April 2016, a SpaceX Falcon Heavy rocket will carry the satellite into orbit, where it will spread its gigantic silver sail and begin to demonstrate controlled solar sailing.
The satellite’s first sail deployment test is scheduled for three weeks from now.
“What we’re focusing on ... is demonstrating the feasibility of solar sailing for CubeSats,” said Jason Davis of the Planetary Society. “We’d love to see the day when CubeSats head out of Earth’s orbit to monitor the sun, visit the moon or take trips to Mars.”
Solar propulsion is a relatively new technology. The idea has been around since the 1800s, but it was only in 2010 that the first spacecraft, the Japanese-made IKAROS, was able to use it effectively. A large, reflective “sail” extended by a spacecraft catches light to provide a small amount of acceleration. The smaller the mass of the satellite, the greater its acceleration — thus the reason for the “nanosatellite” being the size of a loaf of bread.
Another satellite carried on the same rocket, Prox-1, will do several flybys of LightSail-1 as it unfurls its solar sails and take pictures to illustrate the potential uses of solar sailing.
Although solar sails may be practical for nanosatellites, larger spacecraft won’t be seeing solar sails anytime soon.
“In theory, it’s certainly possible, but not very practical at the moment,” said Davis. He has a point: a craft the size of the Space Shuttle, even with a solar sail a kilometer long on a side, would experience a relatively small acceleration due to its large mass — about one thousandth of a meter per second. At that rate, from low Earth orbit, it would take more than a month to just reach the moon, and that’s without accounting for the time required to slow down for landing.
“I don’t think we’ll see solar sails propelling humans anytime soon,” Davis added.
The Planetary Society is also trying to gather funding for a probe to explore the atmosphere and surface of Jupiter’s moon Europa in search of life, as its surface conditions may be similar to those in the Arctic. If the cost were spread out over every American, according to Planetary Society CEO Bill Nye, it would be “the equivalent of one reasonably priced burrito,” or about $2 billion total.
For more information, visit planetary.org.