In a live webcast, The Planetary Society CEO Bill Nye announced that its long-awaited LightSail solar sail mission will launch to Earth orbit on a SpaceX Falcon Heavy, currently scheduled for an April 2016 liftoff. LightSail-1 and its parent satellite, Prox-1, will be on the same launch vehicle as the U.S. Air Force’s Space Test Program 2 (STP-2) mission. If successful, it will be the first CubeSat to demonstrate controlled solar sailing.
“It’s fantastic that at last we have a launch date for this pioneering mission,” said Nye.
The Planetary Society has raised over $4 million for the mission, but according to Jason Davis from TPS, the launch costs will be paid by the USAF and Georgia Institute of Technology, which developed the Prox-1, a technology demonstration for using small satellites to autonomously inspect other spacecraft.
LightSail will go to an orbit about 720 km above Earth, stored inside the Prox-1, which was developed by the Georgia Institute of Technology to demonstrate new technologies enabling two spacecraft to work in close proximity. After ejecting LightSail, the largely student-built Prox-1 will track and image LightSail, including the sail deployment.
Here’s the LightSail-1 mission trailer:
According to TPS, cubesats utilize a standard design based on 10-centimeter (about 4-inch) cubes. LightSail is three cubes, or just 30 centimeters long. Tucked inside this tiny package are four ultra-thin Mylar sails that will be deployed a few weeks after orbital insertion. The reflective wings will expand to 32 square meters (344 square feet), making LightSail easily visible to naked eye observers on Earth.
There might be a test flight of a prototype LightSail-A on a smaller rocket, perhaps in 2015. This flight will only reach low earth orbit, where the atmosphere is too thick for a solar sail to function, but it will allow the LightSail team to check the operation of vital systems in the extreme environment of space. That team includes faculty and students at California Polytechnic State University in San Luis Obispo.
While the test flight would only stay in orbit for a week or so, the 2016 main LightSail mission should remain in orbit for several years.
Solar sails are not new, and have already been launched and deployed in space, but have had limited success. The Japanese Ikaros satellite unfurled a 14-meter solar sail back in 2010. NASA launched the Nanosail-D spacecraft in 2011 and is expected to launch the Sunjammer solar sail in early 2015.
A spacecraft propelled by a solar sail uses the sail to capture photons emitted from the Sun. Over time, the buildup of the solar photons provides enough thrust for a small spacecraft to travel in space. Solar sails could one day be an alternative to conventional propellant-based spacecraft.
The Planetary Society has a long history of solar sail activity. In June 2005, the Society attempted to launch Cosmos 1, which would have been the first solar sail in space. The failure of a Russian booster doomed that effort, but then proceeded with fundraising for the Lightsail mission.
Find out more details about the LightSail mission at the Planetary Society, and here’s Fraser with more details about solar sails: