Is our world unique? Is it the only one in existence, or are there others – perhaps many others – out there? Do other beings – maybe even intelligent ones – call these worlds their home, and live out their lives completely unbeknownst to us?
It was only in 1995 that we first discovered evidence that other stars had planets, as ours does. Now we have detected many thousands of other worlds, and evidence suggests that a majority of sun-like stars possess them. Most of these stellar systems bear little resemblance to ours. The easiest planets to detect are massive worlds located close to their stars, so "hot Jupiters" dominate the current list of exoplanets. As our surveys continue, however, we are discovering more and more Neptunes and even super-Earths, in orbits farther and farther from their suns.
How to Search for Exoplanets
How are scientists searching for extrasolar planets? Read here of the different approaches, their strengths and weaknesses, and how planet hunters are pursuing them all.
Catalog of Exoplanets
We recommend the Paris Observatory's Extrasolar Planets Encyclopaedia. The Planetary Society no longer maintains our own Catalog of Exoplanets.
Our Exoplanets Research
What have the recent discoveries of thousands of exoplanets told us about how we got here, and whether we are alone? In Destiny or Chance Revisited, Stuart Ross Taylor attempts to answer those two questions.
The Planetary Society sponsored Alpha Centauri planet search started using a newly upgraded system in May. Here is a quick update including info from project leader Debra Fischer from Yale about their new system.
Emily Lakdawalla and Courtney Dressing talked about just how common Earth-sized exoplanets may be in our neighborhood. Watch the replay here.
Join Casey Dreier and Emily Lakdawalla as they are joined by Dr. Meg Schwamb from Yale University. They will discuss the latest announcements from the American Astronomical Society 2013 conference and Dr. Schwamb's research in outer solar system bodies.
This year's American Astronomical Society meeting featured tons and tons of news on exoplanets. They're everywhere! And not just planets, but also asteroids, comets, and more....
European astronomers have made the first planetary discovery in the closest-to-Earth Alpha Centauri star system. Here is some information about the discovery, and insights from Yale Astronomer Debra Fischer, who leads another Alpha Centauri planet search partially supported by The Planetary Society.
In the first full day of the annual meeting of the Division of Planetary Sciences of the American Astronomical Society, I listened to scientific sessions on icy worlds and on an exoplanet in a four-star system.
The excitement is building! LightSail is counting down to our test launch, set for May 20—and you’re invited.