 Its orbital eccentricity is very large ("e" = 0.5).Since tidal forces should have reduced the orbital eccentricity of this planet it was speculated that another massive planet found outside the orbit of HAT-P-2b is in orbital resonance with HAT-P-2b.Additional measurements taken over six years show a long-term linear trend in the radial velocity data consistent with a companion of 15 Jupiter masses or greater.