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
Earth and its solar system compatriots all have nearly circular orbits, but many exoplanets orbit their stars on wildly eccentric paths. Is our home system strange? Or is our sense of the data skewed?
Posted by Bruce Betts on 2014/04/25 04:30 CDT
Learn about the formation and origin of the Solar System and go beyond our neighborhood to investigate exoplanets (planets around other stars) in this video of class 11 of Bruce Betts' Introduction to Planetary Science and Astronomy class.
Update from Debra Fischer and her team on the intriguing results of their observations of the main Alpha Centauri stars, as well as future plans.
Our own Dr. Bruce Betts is once again teaching his Introduction to Planetary Science and Astronomy college course online. Come join him.
An update from Yale’s Debra Fischer about the Alpha Centauri planet hunt, partially sponsored by The Planetary Society, as well as her team’s efforts to remove “noise” from parent stars to help find exoplanets.
The European Space Agency will announce two major science missions this November, one of which is likely to be devoted to solar system exploration.
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.
An asteroid or comet headed for Earth is the only large-scale natural disaster we can prevent. Working together to fund our Shoemaker NEO Grants for astronomers, we can help save the world.