Title: Stellar Spin-Orbit Misalignment in a Multiplanet System Author: Daniel Huber, Joshua A. Carter, Mauro Barbieri, Andrea Miglio, Katherine M. Deck, Daniel C. Fabrycky, Benjamin T. Montet, Lars A. Buchhave, William J. Chaplin, Saskia Hekker, Josefina Montalbán, Roberto Sanchis-Ojeda, Sarbani Basu, Timothy R. Bedding, Tiago L. Campante, J\orgen Christensen-Dalsgaard, Yvonne P. Elsworth, Dennis Stello, Torben Arentoft, Eric B. Ford, Ronald L. Gilliland, Rasmus Handberg, Andrew W. Howard, Howard Isaacson, John Asher Johnson, Christoffer Karoff, Steven D. Kawaler, Hans Kjeldsen, David W. Latham, Mikkel N. Lund, Mia Lundkvist, Geoffrey W. Marcy, Travis S. Metcalfe, Joshua N. Winn
Stars hosting hot Jupiters are often observed to have high obliquities, whereas stars with multiple co-planar planets have been seen to have low obliquities. This has been interpreted as evidence that hot-Jupiter formation is linked to dynamical disruption, as opposed to planet migration through a protoplanetary disk. We used asteroseismology to measure a large obliquity for Kepler-56, a red giant star hosting two transiting co-planar planets. These observations show that spin-orbit misalignments are not confined to hot-Jupiter systems. Misalignments in a broader class of systems had been predicted as a consequence of torques from wide-orbiting companions, and indeed radial-velocity measurements revealed a third companion in a wide orbit in the Kepler-56 system.
Observations from NASA's Kepler spacecraft have uncovered a 'tilted' solar system, a finding that gives clues as to how some planets come to orbit their stars on paths that are misaligned with the stars' equators, astronomers report today in Science. Five years ago, however, astronomers were shocked to find planets orbiting at steep angles to their stars' equators. Some planets even went around their suns backwards - they orbit in the opposite direction to the star's rotation3. But no one had seen a misaligned multiplanetary solar system until now. Read more
Iowa State astronomer helps research team see misaligned planets in distant system
Using data from NASA's Kepler space telescope, an international team of astronomers has discovered a distant planetary system featuring multiple planets orbiting at a severe tilt to their host star. 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. Read more