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 are scientists searching for extrasolar planets? Read here of the different approaches, their strengths and weaknesses, and how planet hunters are pursuing them all.
We recommend the Paris Observatory's Extrasolar Planets Encyclopaedia. The Planetary Society no longer maintains our own Catalog of Exoplanets.
Our newest sponsored project uses a triple-laser system to support precise, long-term spectrograph calibrations.
Are there Earth-like planets around our nearest stellar neighbor?
FINDS Exo-Earths is a fiber-optic spectrograph technology that helps exoplanet hunters look for worlds beyond our solar system.
Jason Rhodes • June 23, 2017 • 8
Starshade is a proposed flower-shaped spacecraft that can create an artificial eclipse, allowing space telescopes to spot planets orbiting distant stars.
Franck Marchis • February 22, 2017 • 14
Scientists have found seven, Earth-size planets orbiting a star just 40 light years away. Three lie in the habitable zone and could have water on their surfaces.
Erika Nesvold • October 31, 2016
At this year’s Division for Planetary Sciences/European Planetary Science Congress meeting, the Exoplanet Dynamics session was packed full of talks on tightly-packed multi-planet systems and their instabilities.
Franck Marchis • August 24, 2016 • 19
What began as a tantalizing rumor has just become an astonishing fact. Today a group of thirty-one scientists announced the discovery of a terrestrial exoplanet orbiting Proxima Centauri. The discovery of this planet, Proxima Centauri b, is a huge breakthrough not just for astronomers but for all of us. Here’s why.
Anna Scott • June 07, 2016 • 4
Jet streams are found in planetary atmospheres throughout our solar system. But what exactly are they?
Anna Scott • April 20, 2016 • 4
There are two types of atmospheric waves that are critically important on Earth and other planets: gravity waves and planetary waves.
Jingjing Chen • April 15, 2016 • 6
Until just a few years ago, a plot of mass versus size of other worlds would have looked pretty sparse and uninformative. But thanks to the tireless efforts of exoplanet astronomers, we now know fairly precise masses and radii for hundreds of distant worlds.
Meg Schwamb • March 04, 2016 • 6
Meg Schwamb highlights some of the upcoming space-based missions that will search for planets beyond our solar system.
Bruce Betts • February 04, 2015 • 2
Our own Dr. Bruce Betts is once again teaching his Introduction to Planetary Science and Astronomy college course online. Come join him.
Bruce Betts • September 26, 2014
The Planetary Society is launching a new collaboration with Yale exoplanet hunter Debra Fischer and her team, the Exoplanets Laser project. We will support the purchase of an advanced, ultra stable laser to be used in a complex system they are designing to push radial velocity exoplanet hunting to a whole whole new level.
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LightSail 2 will launch aboard the SpaceX Falcon Heavy. Be part of this epic point in space exploration history!