The AAVSO is an international non-profit organization of variable star observers whose mission is to enable anyone, anywhere, to participate in scientific discovery through variable star astronomy.
The BAA-VSS was formed in 1890, the year the BAA was founded, with the aim of collecting and analysing observations of variable stars. The Section is run by a small group of Officers who deal with various aspects separately but meet at intervals to discuss and decide future plans and policy. Feedback to members is through the VSS Circulars published four times a year and through the BAA Journal.
The Center for Basement Astrophysics (CBA) was founded by David Skillman in the 1970s as a sort of counter-culture version of the perhaps better-known institute in Cambridge, Massachusetts. The single product of the CBA was, and still is, light curves of variable stars.
MicroFUN is an informal consortium of observers dedicated to photometric monitoring of interesting microlensing events in the Galactic Bulge. The primary scientific objective is to observe those high-magnification microlensing events that offer the greatest potential for detecting extra-solar planets orbiting the lensing star.
The Optical Gravitational Lensing Experiment or OGLE is a Polish astronomical project based at the University of Warsaw that is chiefly concerned with discovering dark matter using the microlensing technique. Since the project began in 1992, it has discovered several extrasolar planets as a bonus. The project is led by Andrzej Udalski, who is a co-author of the discovery of OGLE-2005-BLG-390Lb.