The Planetary Society’s pioneering spacecraft LightSail 2 is getting ready for its big moment — deploying the solar sail it carries on board, which should be able to propel the spacecraft using only the force of photons from the Sun striking its surface, if all goes to plan. You can watch live as it undergoes the unfurling process, starting at around 11:40 AM PT (2:40 PM ET) today.

LightSail 2, a spacecraft funded in part thanks to crowdfunding by a community of space enthusiasts, already made history when it launched aboard SpaceX’s Falcon Heavy on June 25. Since then, it’s been orbiting the Earth and undergoing tests to ensure its readiness for its main mission — deploying the sail and studying the results.

The benefits of solar sail propulsion are that it’s very low-cost and could potentially operate for a very long time, allowing us to study the far reaches of space and deliver a variety of payloads on research missions. It’s very low-thrust, however, and takes a long time to get up to speed. And to date, much of what we know about solar sails is still theoretical — one craft called IKAROS was launched in 2010 by the Japan Aerospace Exploration Agency, but there’s lots left to learn, and LightSail 2 could provide crucial experimental data that it intends to make available to the scientific community to study.