OGLE

OGLE (for Optical Gravitational Lensing Experiment) is an astronomical survey that aims to identify MACHOs, i.e., dark matter in the form of brown dwarfs or field planets, by searching for gravitational microlensing events. It surveys regions likely to show such microlensing such as the galactic bulge, Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC). The survey began in 1992 and continues, with phases numbered OGLE-I, II, III, and currently, IV. As a bonus, it has uncovered extra-solar planets by the microlensing technique. Similar projects have been the MACHO Project and EROS.