Both planets were discovered simultaneously by gravitational microlensing in a common effort by the Optical Gravitational Lensing Experiment, microFUN, MOA, PLANET and RoboNet collaborations, as announced on 14 February 2008.
Обе планеты были открыты методом гравитационного микролинзирования в рамках проектов OGLE ("Optical Gravitational Lensing Experiment"), microFUN, MOA, PLANET ("Probing Lensing Anomalies Network") и RoboNet.