Space traveling with Lightsails is gaining speed

Caltech is developing a membrane that could ultimately be used as lightsail

Caltech is leading the worldwide community working toward achieving this audacious goal. “The lightsail will travel faster than any previous spacecraft, with potential to eventually open interstellar distances to direct spacecraft exploration that are now only accessible by remote observation,” explains Harry Atwater, the Otis Booth Leadership Chair of the Division of Engineering and Applied Science and the Howard Hughes Professor of Applied Physics and Materials Science at Caltech.

Now, Atwater and his colleagues at Caltech have developed a platform for characterizing the ultrathin membranes that could one day be used to make these lightsails. Their test platform includes a way to measure the force that lasers exert on the sails and that will be used to send the spacecraft hurtling through space. The team’s experiments mark the first step in moving from theoretical proposals and designs of lightsails to actual observations and measurements of the key concepts and potential materials.

“There are numerous challenges involved in developing a membrane that could ultimately be used as lightsail. It needs to withstand heat, hold its shape under pressure, and ride stably along the axis of a laser beam,” Atwater says. “But before we can begin building such a sail, we need to understand how the materials respond to radiation pressure from lasers. We wanted to know if we could determine the force being exerted on a membrane just by measuring its movements. It turns out we can.”

A paper describing the work appears in the journal Nature Photonics. The lead authors of the paper are postdoctoral scholar in applied physics Lior Michaeli and graduate student in applied physics Ramon Gao (MS ’21), both of Caltech … read further