exoplanet

Roughly 25 trillion miles (or 4.3 light years) from home, astronomers have found that the Alpha Centauri star system hosts a planet with a mass similar to that of Earth. Galactic geeks may recall references to this star system in "Star Trek," "Avatar," "Transformers," and countless other fictional entertainment.

The planet, officially named Alpha Centauri Bb, orbits Alpha Centauri B and took more than four years of observing to fully classify. … Read more

For anyone who's seen the film "Contact," the search for extraterrestrial intelligence is a very noble cause. And over the last 35 years, Jill Tarter, who was the inspiration for Jodie Foster's character, has become known as the world's most famous alien hunter.

For years, Tarter has been the director of the Center for SETI Research, and in that position, she has worked harder than almost anyone on the planet to try to find new friends in the skies. So far, her work, and that of her many colleagues around the world, has been unrewarded. Yet, in spite of constant battles for funding and the skepticism of those who believe we're alone in the universe, Tarter has persevered, and SETI has continued. … Read more

Astronomers are increasingly sure that Earth-like planets aren't so unique after all.

A multiyear study done by the European Southern Observatory (ESO) concludes there are tens of billions of rocky planets in potentially habitable zones in the Milky Way.

The analysis also found there are about 100 "super Earths," or planets with masses between one and 10 times that of Earth, orbiting stars that are relatively nearby. The astronomers define "neighboring" as about 30 light-years away.

ESO researchers used a technique for detecting the presence of planets around red dwarf stars, the most common type … Read more

A mere 60 light-years away, orbiting an orangish star called HD 189733, is a world an Earthling would not want to visit. The planet is a gas giant, like Jupiter or Saturn, but unlike those familiar worlds this one hugs tightly to its host star, orbiting at about one thirtieth the distance at which Earth circles the sun. The exoplanet, labeled HD 189733 b by astronomical convention, stays mighty toasty under its astronomical broiler, with temperatures upward of 900 degrees Celsius.

Thanks to a new study, any hypothetical unfortunates forced to visit HD 189733 b will know which part of … Read more

Astronomers are finding lots of exoplanets that are orbiting stars like the sun, significantly raising the odds that we will find a similar world. But if we do, the chance that the surface of that planet will look like ours is very small, thanks to an unlikely culprit: plants.

We all know how Earth's landscape came about, right? Oceans and land masses formed, mountains rose, and precipitation washed over its surface; rivers weathered bare rock to create soil and plants took root. Well, new research indicates that the last stage of this scenario is not right. Vascular plants--those with … Read more

The next time you look up at the night sky and find yourself marveling at the number of stars overhead, know that you are only seeing part of the magnificent bounty that our galaxy holds. Most of those Milky Way stars are not isolated orbs. Rather, an average star has at least one planetary companion, invisible to the naked eye and in most cases as yet unseen by telescopes, according to a new analysis.

That extrasolar planets should be even more common than stars, which themselves seem innumerable, lends support to the hope that somewhere up in the night sky, … Read more

NASA's Kepler space telescope has found the first confirmed Earth-size planets orbiting another star, astronomers announced Tuesday, a major milestone in an ongoing project aimed at finding out how commonplace--or rare--Earth-like worlds may be across the cosmos.

In a solar system 1,000 light years away with at least five planets, the newly confirmed Earth-size worlds orbit too close to their star to support life. But proving the Kepler observatory can, in fact, spot worlds as small as Earth across the vast reaches of interstellar space gives astronomers confidence many more such planets are awaiting discovery among the 2,… Read more

For the first time, astronomers using NASA's Kepler space telescope have confirmed a roughly Earth-size planet orbiting a sun-like star in the so-called "Goldilocks" zone where water can exist in liquid form on the surface and conditions may be favorable for life as it is known on Earth.

Along with the confirmed extra-solar planet, one of 28 discovered so far by Kepler, researchers today also announced the discovery of 1,094 new exoplanet candidates, pushing the spacecraft's total so far to 2,326, including 10 candidate Earth-size worlds orbiting in the habitable zones of their parent … Read more

NASA's Kepler space telescope, searching for planets around distant suns, has discovered a Saturn-size world orbiting two stars 200 light years from Earth, a long-sought "circumbinary" planet reminiscent of the fictional world Tatooine in the Star Wars saga.

"This is the first definitive detection of a circumbinary planet and the best example we have of a Tatooine-type world," said Laurance Doyle, a researcher at the SETI Institute's Carl Sagan Center for the Study of Life in the Universe and lead author of a paper in the journal Science describing the discovery.

"Now, we … Read more