Delayed NASA Solar Sail Satellite Finally Orbits

January 26, 2011

Rendering of a kite-like satellite in space with Earth in the background.

An artist's concept of the NanoSail-D solar sail in space.
Credit: NASA

In an unexpected twist for what was thought to be a failed space mission, NASA engineers confirmed on January 21 that the NanoSail-D "nanosatellite" had deployed its 100-square-foot polymer solar sail in low-Earth orbit and is operating—more than a month later than originally planned. The sail actually unfurled on January 20, NASA's Marshall Space Flight Center in Huntsville, Alabama, reported, marking the first time the United States has achieved low-Earth solar sail flight. The device will stay in a low orbit for between 70 and 120 days, depending on atmospheric conditions.

The saga of the satellite began on November 19 when NanoSail-D launched from Kodiak Island, Alaska, aboard the Fast, Affordable, Science and Technology Satellite (FASTSAT), itself a compact microsatellite. The original schedule called for the mini-satellite, about the size of a loaf of bread, to eject on December 6. After initially reporting the NanoSail had left FASTSAT, the launch team reconsidered after finding no evidence the tiny package was in orbit. Because the separation was unexpectedly delayed, the mission appeared in jeopardy. But recently, the nanosatellite did "spontaneously" emerge, which engineers confirmed on January 19. Once that free flight occurred about 400 miles above the Earth's surface, a timer within NanoSail-D began a three-day countdown, and when it reached zero, four booms were programmed to quickly deploy, allowing NanoSail-D to unfold the polymer sail in five seconds.

The sail, described as the size of a tent, is linked to eight lithium-ion batteries as a power source. The mission is designed to test an emerging technology that will decrease the time a satellite needs to de-orbit without using the propellants that most traditional satellites use. The first attempt to launch and deploy NanoSail-D was in August 2008. The Falcon 1 rocket experienced problems that resulted in the loss of the launch vehicle and payloads, including the first NanoSail-D. However, NASA engineers had constructed two NanoSail-D flight units, in case one failed or another launch opportunity became available. Now, NASA has formed a partnership with to encourage the amateur astronomy community to submit the best photographic images of the orbiting NanoSail-D, with prizes for the best pictures. See NASA press releases on deployment and first signals, as well as a NanoSail-D fact sheetPDF, and the photo contest.