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, …

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 …

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.

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

For over 4 decades, our members have made strides in advancing planetary exploration, planetary defense, and the search for life beyond Earth. We have delivered tens of thousands of petitions to …

Jan 9, 2026 · This is our nation’s highest-priority planetary science mission according to the 2023 Planetary Sciences Decadal Survey and is critical to paving the way for eventual exploration of the …

To figure out where that boundary lies, and how geoscientists might classify planets, it helps to know what planetary scientists have learned about the variety of worlds in our solar system, and which …

The Planetary Society is working to change the launch date to 2029. ESA's EnVision will launch no earlier than 2031 to investigate Venus' atmosphere and overall structure.