The 100 square foot sail was deployed from a science satellite launched in November, 2010 and unfurled its sail on January 20, 2011. A proof of concept vehicle, Nanosail-D will only fly for between 70 and 120 days before falling to Earth and disintegrating harmlessly into the atmosphere.
NanoSail-D was launched as one of six experiments on the Fast, Affordable, Science and Technology Satellite (FASTSAT) in Noveber, 2010. It was designed to separate from FASTSAT soon after launch, release its sail, and begin its mission. However, the sail was stuck inside its parent satellite for about six weeks before it spontaneously broke free on January 17, 2011. Independent radio contact was made by the amateur radio club at Marshall Space Flight Center the next day (Ham radio operators continue to track signals from NanoSail-D) and the sail itself – previously held in place by 50 pound fishing wire – was unfurled at 10pm EST on January 20th. Although clearly not a smooth process, the deployment of NanoSail-D proved it was possible to deploy miniature satellites from larger satellites rather than from manned vehicles or directly on rockets from Earth.
The Japanese Space Agency has deployed a solar sail on a mission to Venus, but NanoSail-D was designed to remain in low Earth orbit. It was designed to test the feasibility of using solar sails to safely bring old and obsolete satellites to Earth once their useful lifetime has passed. Space debris is a growing issue; preventing future satellites from littering near Earth space in the future is important if we wish to continue deploying limited lifetime satellites on an ongoing basis.
The key to this return process is the aerodynamic drag on solar sails as they skim the top of the Earth’s atmosphere. This drag eventually forces the satellite out of its orbit and fully back into the atmosphere were it harmlessly breaks up. Future satellites could be equipped with compact solar sails that are unfurled after their missions end, starting the slow process down into the atmosphere and eventual disintegration.
TFOT has previously reported on earlier plans for testing the NanoSail-D (which, unfortunately, failed because of problems with the rocket carrying the sail into space). TFOT has also reported on the Japanese Aerospace Exploration Agency ‘s Ikaros spacecraft powered by a solar sail and the potential of solar sails as a means of maintaining displaced orbits.
Read more about the NanoSail-D deployment in this NASA press release.