An uncommon Saturn-mass planet consisting of half rock and half gas that is located some 200 light years away from Earth with two suns has been discovered by Kepler spacecraft.
The rare planet is the first confirmed solar system of its kind. The rare planet orbits two stars, as portrayed in the sci-fi movie Star Wars more than 30 years ago. Star Wars portrayed the existence of a planet called Tatooine which has two sunsets. Now, it has become a reality after 34 years.
“This discovery confirms a new class of planetary systems that could harbor life. Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars, said Kepler principal investigator William Borucki in a NASA statement. “I am going to guess there are 2 million more such dual-sun planets,” said Laurance Doyle, the lead researcher on the Kepler-16b report.
While the main purpose of the Kepler telescope is to search for Earth-like planets, Doyle took the lead in using the instrument to search for planets orbiting two suns. He said he has been trying to find such a planet for 20 years.
The astronomers observed that the brightness of the system dipped even when the stars were not eclipsing one another, hinting at a third body.
The additional dimming in brightness events, called the tertiary and quaternary eclipses, reappeared at irregular intervals of time, indicating that the stars were in different positions in their orbit each time the third body passed. This showed that the third body was circling, not just one, but both stars, in a wide circumbinary orbit.
The two stars which Kepler-16b orbits are said to be smaller and cooler than our sun. The stars are 20 and 69 percent as massive as the sun and circle each other every 41 days, said researchers in their report published online in the Sept. 16 issue of journal Science.
Known as Kepler-16b, the new planet detected by Kepler has a pair of orbiting stars that eclipse each other from our vantage point on Earth. When the smaller star partially blocks the larger star, a primary eclipse occurs, and a secondary eclipse occurs when the smaller star is occulted, or completely blocked, by the larger star.
The planet will cease transiting one star as early as 2014 and will stop crossing the second and brighter star in 2018. After that, the planet will remain undetectable using the transit method until around 2042.