NASA Sunjammer Solar Sail Set for Launch Next Year

Sunjammer solar sail. (Credit: L’Garde)

WASHINGTON (NASA PR) — The concept of a huge, ultra-thin sail unfurling in space, using the pressure of sunlight to provide propellant-free transport, hovering and exploration capabilities, may seem like the stuff of science fiction, but a NASA research team developing the Technology Demonstration Mission known as Sunjammer (a.k.a., In-Space Demonstration of a Mission-Capable Solar Sail) intend to prove the viability and value of the technology in 2014.

Led by industry manufacturer L’Garde Inc. of Tustin, Calif., and including participation by the National Oceanic and Atmospheric Administration, the Solar Sail Demonstration mission builds on two successful ground-deployment experiments led by L’Garde in 2005-2006 in a vacuum chamber at the Plum Brook Facility in Sandusky, Ohio, a research laboratory managed by NASA’s Glenn Research Center in Cleveland. It also leverages the successful deployment of the NanoSail-D sail, a 100-square-foot test article NASA launched to Earth orbit in early 2011 to validate sail deployment techniques.

During its own test flight, the new Solar Sail Demonstration mission — dubbed “Sunjammer” by its designers in honor of the 1964 Arthur C. Clarke story of the same name, in which he coined the term “solar sailing” — will deploy and operate a sail approximately 124 feet on a side. That’s almost 13,000 square feet, or a third of an acre — seven times larger than any solar sail tested in space to date. But when collapsed, it’s the size of a dishwasher and weighs just 70 pounds. Attached to a 175-pound disposable support module, the Sunjammer is easily packed into a secondary payload on a Falcon 9 rocket bound for low-Earth orbit.

Credit: L’Garde

The sail will unfurl in space to catch the sunlight. During the flight experiment, researchers will test attitude controls and assess sail stability and their ability to trim. They also will execute a navigation sequence with mission-capable accuracy.

Once proven, solar sail technology could enable a host of versatile space missions, including flying an advanced space-weather warning system to more quickly and accurately alert satellite operators and utilities on Earth of geomagnetic storms caused by coronal mass ejections from the sun. The technology also could provide an economical solution to removing some of the more than 8,000 pieces of orbital launch debris ringing the planet; conduct station-keeping operations, or hover at high latitudes above Earth for communications and observation; and could drive a variety of propellantless, deep-space exploration and supply ferrying missions.

L’Garde Sunjammer Project Description

With this Solar Sail Technology Demonstration Mission (TDM), L’Garde will advance the state of the art of solar sailing.  The end goal of this mission is the deployment, flight, and navigation of a mission capable solar sail to demonstrably prove the efficacy of solar sails.  This proposed mission will definitively advance the technology of solar sailing for use by future mission planners.

Sunjammer stowed and deployment configurations to scale. (Credit: L’Garde)

Solar sails offer many potential game-changing mission capabilities including the following:

• Debris collection and removal from orbit.  Debris can be captured and removed from orbit over a period of years using the small solar-sail thrust.
• De-orbit of spent satellites.  Solar sails can be integrated into satellite payloads so that the satellite can be de-orbited at the end of its mission.
• Creating pseudo-Lagrange points by cancelling some solar gravitational pull with the sails.  As an example, the GeoStorm project considers locating solar storm warning satellites three times further from the Earth increasing warning time from 15 minutes to 45 minutes.
• Providing synchronous satellites at non-equatorial latitudes, such as the “pole-sitter” project.  This allows the northern and southern latitudes to gain the advantages of synchronous satellites.
• Providing deep space propulsion.  Payloads free of the Earth’s pull can be accelerated to the other planets, or out of the solar system, such as those proposed for Project Encounter.

However, without a definitive demonstration of a mission capable solar sail the technology is relegated to the realms of conceptual design.  This TDM aims to boost the Technology Readiness Level (TRL) of the L’Garde solar sail from ~6 to ~9.  The four main objectives of the mission are:

1. Demonstrate segmented deployment of a solar sail with ~4X the area of that vacuum tested at Plum Brook, “cookie cut” from the center of a much larger sail.
2. Demonstrate attitude control plus passive stability and trim using beam-tip vanes.
3. Execute a navigation sequence with mission-capable accuracy.
4. Fly to and Maintain Position at L1 and pole sitter positions.

Learn more about the Sunjammer mission here.