The plan for NEA Scout is to one-up IKAROS by using the sail to reach a specific target and perform a detailed reconnaissance for the first time. “Our technology goal is to demonstrate the ability of a solar sail to propel and navigate a spacecraft through space,” Johnson says. “Our science goal is to take photos of and characterize a near-earth asteroid.
In space, with no air to compete with, light pressure acts as a gentle but persistent wind, strong enough to move a spacecraft. “This will be the first time navigating by light in Earth orbit,” says Bill Nye, CEO of The Planetary Society, the Pasadena-based nonprofit organization that developed and funded LightSail 2. “We hope to increase the orbital energy or altitude, and change the inclination of the orbit by tacking the spacecraft like a sailboat.
Once in deep space, the craft spun open a 46-foot-wide square sail and, for the first time in history, began steering and changing its speed by harnessing sunshine. “It was one of the most moving moments in my life,” Yuichi Tsuda of the Japan Aerospace Exploration Agency (JAXA) told MACH in an email.
Over the next three years, IKAROS measured the acceleration due to light pressure and tested ways to control its motion using liquid crystals in the sail (similar to an LCD electronic display) that could make it more or less reflective. “We fulfilled all our goals perfectly,” Tsuda said, reporting that the craft had been able to adjust both its course and its orientation by navigating into the wind of sunshine.
David Carroll, president of CU Aerospace, says CubeSail was conceived as a first step toward UltraSail, an enormous four-winged sailing craft that the company has been designing for years. “The beauty of the UltraSail concept is the ability to tack the sails, allowing you to travel all over the solar system back and forth as desired without requiring any sort of refueling,” Carroll says.