Solar sail 'bends' light to fly in space

Researchers are developing a new Solar sail design that helps spacecraft navigate through space without fuel.

Simulation of a diffracted solar sail.

A project to develop an advanced solar sail has entered the final phase of NASA's research program. Phase 3 of the Innovative Advanced Concepts (NIAC) program will allow researchers to continue to explore and develop the diffraction solar sail for two years at a cost of $2 million. This funding will help promote the design of the solar sail for wider application.

"As we get further into space than we have in the past, we need cutting-edge and cutting-edge technology to carry out the mission," said NASA Administrator Bill Nelson. "NASA's Innovative Advanced Concepts program helps bring ideas like the solar sail closer to reality."

Just like a normal sail on a boat uses wind to create motion, a solar sail works by using the pressure created by sunlight to move through space. As photons bounce off the mirror-like surface, their momentum propels the sail forward without the use of fuel. The current refractor solar sail design is quite large, thin and often limited in direction of travel. However, a diffracted Solar sail with small squares on thin film can be smaller, more flexible, and easier to steer.

The concept of a diffracted solar sail was first selected for phases 1 and 2 of the NIAC in 2019. During those two phases and testing, a research team examined several materials for the construction of the wing. sails, and develop navigation and control for the Sun's pole orbit. Both stages feature weather tests to test their ability to survive UV exposure. In phase 3, the researchers will optimize the fabrication materials and conduct ground testing in preparation for the mission to the Sun.

The Indian government launched missions powered by solar sails to support communications satellites in 1992 and 2003. The Japanese Space Exploration Agency (JAXA) successfully launched the new IKAROS-equipped spacecraft. Solar sails in 2010 to study Venus and the Sun. Since then, NASA and the non-profit research organization Planetary Society have both successfully launched spacecraft equipped with solar sails to low Earth orbit.