Astronomers have found two more new planets orbiting binary stars: Kepler-34b and Kepler-35b. Their discovery, which follows the original Tatooine discovery back in September 2011, is quite important: now we know there are millions of planets orbiting binary stars.
According to the University of Florida's associate professor of astronomy, Eric B. Ford, these planets seem to be surprisingly common:
"We have long believed these kinds of planets to be possible, but they have been very difficult to detect for various technical reasons. With the discoveries of Kepler-16b, 34b and 35b, the Kepler mission has shown that the galaxy abounds with millions of planets orbiting two stars."
The team lead by William F. Welsh, associate professor at San Diego State University, found that Kepler-34b completes its orbit every 288 terrestrial days and is comparable to Jupiter in size, but less massive: 24 smaller but with 78 per cent less mass.
Kepler-35b is bigger than 34b, with 88 per cent less mass than Jupiter. It's 26 per cent smaller than our solar system gas giant. Both planets are made primarily of hydrogen and they are way too hot too sustain any kind of life.
Astronomers are also starting to think about the weather in these planets, according to Ford:
"Circumbinary planets can have much more complex climates, since the distance between the planet and each star change significantly during each orbital period, the length of an alien planet's year. For Kepler-35b, the amount of incoming star light changes by over 50 percent within a single Earth year. For Kepler-34b, each Earth-year brings ‘summers' with 2.3 times as much star light as winters. Over the course of a year, the change in the amount of sunlight heating the Earth varies by only 6 per cent."
Summary: living on these planets — if you could — would not be an experience that your average Luke Skywalker-wannabe could imagine. [University of Florida]