sentences:  Udry's team employed the radial velocity technique, in which the mass of a planet is determined based on the small perturbations it induces in its parent star's orbit via gravity.In September 2012, Roman Baluev filtered out the "red noise" from the Keck data and concluded that this planet's existence is probable only to 2.2 standard deviations.That same year, however, a team from the USNO confirmed the existence of the planet with a much higher probability.