The Planetary Society

The Planetary Society is the world's largest independent space advocacy organization, founded in 1980 by Carl Sagan, Bruce Murray, and Louis Friedman at Caltech to build public and political support for planetary exploration, SETI, and the search for life beyond Earth. Based in Pasadena, California, the Society has over 50,000 paying members across more than 100 countries and engages millions more through its online platforms, the Planetary Report magazine, and the Planetary Radio podcast.

The organization conducts actual spaceflight projects in addition to advocacy: its LightSail program developed two solar sail spacecraft — LightSail-1 (2015) and LightSail-2 (2019) — demonstrating solar radiation pressure propulsion for CubeSats in partnership with Georgia Tech's SSDL and Cal Poly San Luis Obispo. LightSail-2 successfully used solar sailing to raise its orbit, validating the technology for future low-cost deep space propulsion.

The Society lobbies the U.S. Congress and international governments on space science budget allocations, frequently testifying in support of NASA planetary science programs such as the Europa Clipper, Mars Sample Return, and Uranus orbiter missions. It campaigns against cuts to NASA's planetary science division and supports policies enabling SETI research. Bill Nye ('the Science Guy') has served as CEO since 2010, dramatically increasing the organization's public profile. The Planetary Society's member-funded model makes it financially independent of government contracts, giving it credibility to advocate on contentious budget debates.

Revenue from memberships, the Cosmos Studio educational programs, and major donor contributions from people like Yuri Milner and public celebrities funds both operations and the LightSail project series.