Three-Unit Cubesat Will 'Piggyback' On Larger Mission
NASA announced this week that the Planetary Society's
LightSail-1 solar sail mission is on their short list for upcoming
launch opportunities. The missions selected are Cubesats destined
for piggyback launches as part of NASA's CubeSat Launch Initiative.
"This is great news," said Louis Friedman, Program Director for
LightSail-1. "Our spacecraft will be ready this summer, and we are
hoping for the earliest launch possible."
LightSail-1 is a three-unit Cubesat, which weighs 4.5 kg and
measures only 10x10x30 cm. Cubesats are a type of nanosatellite
that NASA and others launch as auxiliary payloads, "piggybacking"
on missions with larger, conventional spacecraft. NASA has selected
20 (Cubesat) payloads, including LightSail-1, as well as payloads
from government centers and universities.
"We are delighted that NASA has chosen our mission," said Bill
Nye, Executive Director of the Planetary Society. "Our spacecraft
was built with donations from citizens all over the world. It's the
first solar sail spacecraft maneuverable enough to tack and
increase its orbital energy while in Earth Orbit."
Bill Nye
Several launch opportunities from government agencies and
commercial companies have been identified as possibilities for
LightSail-1, both in the U.S. and abroad. LightSail-1 is to
demonstrate controlled solar sail flight with no force other than
sunlight pressure propelling the spacecraft. The minimum desired
altitude is 825 km.
"Our launch requirements are a bit more difficult than typical
Cubesats because we want to go to a high enough altitude so that
our sail will feel no atmospheric effects; being manifested on
NASA's list will help our chances greatly," said Friedman.
The launch of LightSail-1 is in cooperation with the NASA Ames
Research Center (ARC) through a no-exchange-of-funds Space Act
Agreement the Society and ARC have made for nanosatellite
development and educational activities.
LightSail-1 will break new ground as a fully capable
nanosatellite with two cameras, on-board accelerometers, radio
telemetry, an attitude control system, and six solar arrays for
battery charging.
The spacecraft is being built by Stellar Exploration, Inc. of
San Luis Obispo in cooperation with California Polytechnic
University. The solar sail is 5.5x5.5 meters of 4.6 micron Mylar,
with a novel motorized deployment mechanism invented specifically
for this project. The sail booms are developed by the Air Force
Research Laboratory.