sail.jpg "NASA solar sail")
An artist's concept of a solar sail in Earth orbit.
Credit: NASA
MARYLAND: In an unexpected reversal of fortune, NASA's NanoSail-D spacecraft has unfurled a gleaming sheet of space-age fabric 650 km above Earth, becoming the first-ever solar sail to circle our planet.
NanoSail-D spent the previous month and a half stuck inside its mothership, the Fast, Affordable, Science and Technology SATellite (FASTSAT). FASTSAT was launched in November 2010 with NanoSail-D and five other experiments onboard.
High above Earth, a spring was supposed to push the breadbox-sized probe into an orbit of its own with room to unfurl a sail. But when the big moment arrived, NanoSail-D got stuck.
Flight a shock for everyone
"We couldn't get out of FASTSAT," said Alhorn. "It was heart-wrenching—yet another failure in the long and troubled history of solar sails."
Team members began to give up hope as weeks went by and NanoSail-D remained stubbornly and inexplicably onboard. The mission seemed to be over before it even began.
And then came January 17th. For reasons engineers still don't fully understand, NanoSail-D spontaneously ejected itself. When Alhorn walked into the control room and saw the telemetry on the screen, he said, "I couldn't believe my eyes. Our spacecraft was flying free!"
Waiting for the sail to unfurl
The team quickly enlisted amateur radio enthusiasts Alan Sieg and Stan Sims at the Marshal Space Flight Center to try to pick up NanoSail-D's radio beacon. "The timing could not have been better," said Sieg. "NanoSail-D was going to track right over Huntsville, and the chance to be the first ones to hear and decode the signal was irresistible."
Then they heard a faint signal. As the spacecraft soared overhead, the signal grew stronger and the operators were able to decode the first packet. NanoSail-D was alive and well.
"You could have scraped Dean off the ceiling. He was bouncing around like a new father," said Sieg.
The biggest moment, however, was still to come. NanoSail-D had to actually unfurl its sail.
