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.

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’s up in the night sky: January 2026 Our monthly feature focuses on easy and fun things to see in the night sky, including eclipses, supermoons, meteor showers, planetary conjunctions, and more.

Apr 30, 2025 · If you love the show, you can get Planetary Radio T-shirts at planetary.org/shop, along with lots of other cool spacey merchandise. Help others discover the passion, beauty, and joy of …

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

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

Jun 26, 2025 · When I wrote the advocacy update for the June issue of the Planetary Report, I could not have imagined the ongoing success of our advocacy efforts this year. But given that NASA and the …

Apr 10, 2025 · How to spot comet SWAN (C/2025 F2) Written by Asa Stahl, PhD Science Editor, The Planetary Society April 10, 2025

Jan 8, 2025 · With a global community of more than 2 million space enthusiasts, The Planetary Society is the world’s largest and most influential space advocacy organization.

May 2, 2025 · With a global community of more than 2 million space enthusiasts, The Planetary Society is the world’s largest and most influential space advocacy organization.