Sailing through space sounds like something out of science fiction. But with the launch of the Advanced Composite Solar Sail System in April, solar sail technology is no longer limited to books and movies.
The technology will be launched by Rocket Lab’s Electron rocket from their Launch Complex 1 in Māhia, New Zealand. This new solar sail technology could revolutionize space travel and our understanding of the Sun and the solar system.
By using the pressure of sunlight for propulsion, solar sails can move a spacecraft by angling toward or away from the Sun, with photons bouncing off the reflective sail to create the necessary thrust. This eliminates the need for heavy propulsion systems, potentially enabling longer-duration and lower-cost missions. However, the material and structure of the booms, which act as the sailboat’s mast, have limited the capabilities of solar sails so far. But NASA is about to change the game for future space travel.
The Advanced Composite Solar Sail System demonstration uses a 12U CubeSat developed by NanoAvionics to test a new composite boom. This new boom is made from flexible polymer and carbon fiber materials that are stiffer and lighter than previous designs, and the primary objective of the mission is to demonstrate the new boom deployment successfully.
Once deployed, the solar sail can adjust its orbit by angling its sail, much like a sailboat turning to capture the wind. Additionally, the team hopes to prove the sail’s performance, test a series of maneuvers to change the spacecraft‘s orbit, and gather data for potential future missions with even larger sails.
“Booms have tended to be either heavy and metallic or made of lightweight composite with a bulky design – neither of which work well for today’s small spacecraft. Solar sails need very large, stable, and lightweight booms that can fold down compactly,” said Keats Wilkie, the mission’s principal investigator at NASA’s Langley Research Center in Hampton, Virginia. “This sail’s booms are tube-shaped and can be squashed flat and rolled like a tape measure into a small package while offering all the advantages of composite materials, like less bending and flexing during temperature changes.”
After reaching its Sun-synchronous orbit, the spacecraft will begin unrolling its composite booms, spanning diagonals of the polymer sail. After around 25 minutes, the solar sail will deploy completely, measuring a huge 860 square feet – equivalent to about six parking spots. It’s quite fascinating to know that spacecraft-mounted cameras will be able to capture the moment of deployment and monitor its shape and symmetry.
If the lighting conditions are just right, with its large sail, the spacecraft might even be visible from Earth. Once fully expanded and at the proper orientation, the sail’s reflective material will be as bright as Sirius, the brightest star in the night sky.
NASA’s Small Spacecraft Technology program is opening up new possibilities for space exploration. The successful deployment and operation of the solar sail’s composite booms will prove the capability and open the door to larger-scale missions to the Moon, Mars, and beyond. This technology could eventually support sails as large as 5,400 square feet (500 square meters) or even up to 21,500 square feet (2,000 square meters).
“The Sun will continue burning for billions of years, so we have a limitless source of propulsion. Instead of launching massive fuel tanks for future missions, we can launch larger sails that use “fuel” already available,” said Rhodes. “We will demonstrate a system that uses this abundant resource to take those next giant steps in exploration and science.”
The potential applications of solar sails beyond just space exploration. Because they use the power of the Sun, they could be used to support missions that require unique vantage points, such as those that seek to understand our Sun and its impact on Earth. They could also be used to carry early warning systems for monitoring solar weather, which can cause considerable damage on Earth.
Additionally, the lightweight design and compact packing system of composite booms could make them useful for constructing habitats on the Moon and Mars, acting as framing structures for buildings or compact antenna poles to create a communications relay for astronauts exploring the lunar surface.
“This technology sparks the imagination, reimagining the whole idea of sailing and applying it to space travel,” said Rudy Aquilina, project manager of the solar sail mission at NASA Ames. “Demonstrating the abilities of solar sails and lightweight, composite booms is the next step in using this technology to inspire future missions.”
