NASA Looks to Commercialize Solar Sail Technology

A concept image of the Near-Earth Asteroid Scout mission, one of 11 missions that will be secondary payloads to the first test flight of NASA's Space Launch System. (Credit: NASA)
A concept image of the Near-Earth Asteroid Scout mission, one of 11 missions that will be secondary payloads to the first test flight of NASA’s Space Launch System. (Credit: NASA)

NASA CubeSat-Scale Solar Sail for Space Propulsion
Solicitation Number: NNM16042116
Agency: National Aeronautics and Space Administration
Office: Marshall Space Flight Center
Location: Office of Procurement

Introduction

A cubesat-scale solar sail propulsion system is being developed at NASA Marshall Space Flight Center to provide propulsion for a 6U interplanetary CubeSat to be used for the Near Earth Asteroid Scout (NEAS) project. NASA MSFC desires for the solar sail technology and design being developed for the NEAS mission to be commercially available after the completion and delivery of the flight system hardware in 2018. To further that goal, NASA MSFC seeks to provide the solar sail propulsion system design to interested commercial entities. It is anticipated that there may be follow-on missions using the NEA Scout sail system following successful completion of the NEA Scout project.

NEA Scout will fly on the Space Launch System (SLS) Exploration Mission 1 (EM-1) mission scheduled for launch in 2018 and is being developed in collaboration with NASA’s Jet Propulsion Laboratory. The solar sail will be allocated the mid-2U stowage volume within the 6U spacecraft bus. NEAS will perform a slow flyby of a NEA within approximately two years of launch. The deployed sail area will be approximately 86 square meters and has a tentative mass allocation of 2.5 kg. Once ejected from the SLS, the NEAS will perform systems checkout and then subsequently deploy the solar sail (nominally within 3-4 days after launch). The solar sail will provide the primary source of flight system delta-V. If the spacecraft is still functioning after the asteroid flyby, then an extended mission to visit a different NEA will be considered.

Solar Sail Overview

The solar sail is based on the technology developed and flown by the NASA NanoSail-D. Four 7.4 m stainless steel Trac booms wrapped on two spools (two overlapping booms per spool) will be deployed by a motor from within the allocated cubesat volume. The booms will pull the sail from its stowed volume as they deploy. The sail material will be 3 micron CP1, an aluminized polyimide that was extensively tested for solar sail applications and used in NASA’s 400 square meter solar sail ground demonstrator project. The solar sail will be stowed spooled, rather than z-folded. Processes related to the fabrication of the booms and substrate material will not be provided as these are commercially available piece-parts used as part of the integrated solar sail system.

The baseline reflective sail area required to meet the mission’s delta-V requirements is 78 square meters. Since part of the sail’s surface will have its reflectivity reduced due to structural reinforcement needs, and taking into account that a few small tears in the sail are almost inevitable, the actual deployed sail area will be approximately 86 square meters, providing some propulsive margin.