HD 128311
HD 128311 or HN Boötis is an orange main-sequence star located approximately 54 light-years away in the constellation of Boötes. Two extrasolar planet candidates have been detected in orbit around this star.In 2002, the discovery of the planet HD 128311 b was announced by Paul Butler. In 2005, the discovery of a second planet HD 128311 c was announced by Steve Vogt.
Most likely, the system has been formed in a very turbulent disc. The authors were able to show with both analytic and numerical models that certain libration modes are readily excited by turbulence. It was initially thought that the system could have been resulted from planet planet scattering, but this is rather unlikely.
