The Lightsail spacecraft has launched into space, on a mission to catch light from the sun with a Mylar sail. Apart from a handful of minor glitches, the systems aboard the revolutionary spacecraft designed and manufactured by the Planetary Society look good and ready to meet the goal of testing equipment for future similar vehicles.
Solar sail spacecraft are a new addition to propulsion systems for vehicles traveling through space. Instead of carrying fuel to feed engines, this design employs enormous sails made of Mylar to capture the pressure of light emanating from the sun.
Although photons of light have no mass at rest, their velocity provides the particles with momentum, which can impart force to the vehicle. Just like using wind to sail a ship on water, the Lightsail spacecraft can ride in the same direction as the path of light, or tack in toward it, in order to head toward the sun.
Two-way communication was established with the vehicle, which took off on May 20, and gyroscopes – which were draining energy supplies aboard the ship – were turned off.
"Telemetry downloaded after the command was sent showed the gyroscopes are now off. Later analysis showed they were 'left on' in the spacecraft's software sequence — a condition that will be changed for the 2016 mission," Jason Davis wrote for the Planetary Society.
The first pictures recorded by the spacecraft are expected to be taken on May 24. The initial pictures will however only show the inside of the vehicle.
Solar panel deployment switches on Lightsail were triggered on the way to space — which may have been the result of vibrations experienced during liftoff.
"This telemetry reading, however, does not necessarily mean the panels are open. The switches were once inadvertently triggered during vibration testing, so it's possible they popped loose during the ride to orbit," Davis explained.
"We'll know for sure after flight day four, when we test out the camera system. This is one time we don't want to see a pretty picture of Earth — it would mean the panels are open."
A temperature sensor attached to a circuit board on the vehicle has also experienced a thermal range between 45 and 80 degrees Fahrenheit as the vessel moves between sunlight and darkness.
Lightsail is a CubeSat satellite — roughly the size of a loaf of bread. This tiny craft launched into space on top of an Atlas 5 rocket also carrying the X-37B mini-shuttle into orbit on a classified space flight for the U.S. Air Force.
This first flight for Lightsail is designed to test technology, and will not have the capability to achieve a full light-powered flight. The launch of the first fully operational solar sail spacecraft is scheduled for 2016.
