Co-founded by Carl Sagan in 1980, The Planetary Society is a member-funded nonprofit organization dedicated to advancing space science and exploration through three core enterprises.

The latest stories from The Planetary Society, featuring humanity's quest to explore worlds, find life, and defend Earth.

We connect with planetary exploration experts from around the world to strengthen our work and support international exploration efforts. Our 50,000+ international membership makes us the largest, …

What is a Planet? It's right there in our name: The Planetary Society. But what is a planet? This seemingly simple question is the subject of much debate. Learn More

They established The Planetary Society to give anyone from anywhere in the world an active role in advancing space exploration. Today, The Planetary Society continues this work, under the …

Together with our members and supporters, we’re on a mission to explore worlds, find life off Earth, and protect our planet from dangerous asteroids. Join us at planetary.org.

Aug 21, 2024 · An overview of the planetary decadal’s recommendations is available here. In brief, the planetary decadal identifies 12 priority science questions and a comprehensive set of mission and …

Jan 1, 2026 · Feb. 28: Planetary alignment. Six planets — Mercury, Venus, Jupiter, Saturn, Uranus, and Neptune — will trace an arc across the night sky, though some (Venus, Jupiter, Saturn) will be much …

Let The Planetary Society’s weekly podcast take you to the outer reaches of the Solar System and beyond. Host Sarah Al-Ahmed visits with scientists, engineers, mission leaders, astronauts, …

Jan 30, 2025 · From funding early Mars rover testing to naming planetary bodies and developing sample return technologies, Planetary Society members have funded contributions to more than 20 missions …