Central Bureau for Astronomical Telegrams

The Central Bureau for Astronomical Telegrams (CBAT) is an official international clearing house for information relating to transient astronomical events.

The CBAT collects and distributes information on comets, natural satellites, novae, meteors, and other transient astronomical events. The CBAT has historically established priority of discovery (who gets credit for it) and announced initial designations and names of new objects.

On behalf of the International Astronomical Union (IAU) from 1920 to 2015, the CBAT distributed IAU Circulars. From the 1920s to 1992, CBAT sent telegrams in urgent cases, although most circulars were sent via regular mail; when telegrams were dropped, the name "telegram" was kept for historical reasons, and the Central Bureau Electronic Telegrams (CBETs) were begun a decade later as a digital-only expanded version of the IAUCs, still issued by e-mail to subscribers and posted at the CBAT website.^[1] Since the mid-1980s the IAU Circulars and the related Minor Planet Circulars have been available electronically.

The CBAT is a non-profit organization, but charges for its IAU Circulars and electronic telegrams to finance its continued operation.