Such tilted orbits had been found in planetary systems featuring a "hot Jupiter," a giant planet in a close orbit to its host star. But, until now, they hadn't been observed in multiplanetary systems without such a big interloping planet.
The lead author of the study is Daniel Huber of NASA's Ames Research Center in Mountain View, Calif. Steve Kawaler, an Iowa State University professor of physics and astronomy and a leader of the Kepler Asteroseismic Investigation, is a co-author.
Kawaler contributed as part of the research team that studied regular changes in the brightness of the host star, Kepler-56, an aging red giant star with two planets in close orbits and a massive third planet in a distant orbit.
By measuring those oscillation frequencies and using spectroscopy data about the star's temperature and chemistry, researchers measured the star's diameter and other properties.
The paper reports Kepler-56 is more than four times the radius of our Sun. Its mass is also 30 percent greater than our Sun. It is about 3,000 light-years from Earth.
Kawaler said he was also part of the team that used studies of the changes in brightness to help determine the tilt of the rotation axis of Kepler-56. That axis is tilted 45 degrees to the line of sight from Earth.
The study has been published in the journal Science.
--ANI (Posted on 18-10-2013)