ZTF

The Zwicky Transient Facility (ZTF) is a wide-field, time-domain astronomical survey that aims to detect transient and variable sources across the northern sky. It was developed as a successor to the Palomar Transient Factory and began operating in 2018 from the Palomar Observatory in California.

ZTF uses the 48-inch Samuel Oschin telescope equipped with a large-format camera that covers about 47 square degrees per exposure. The survey conducts high-cadence observations, primarily in the g- and r-band filters, to enable rapid discovery and characterization of transient events on timescales ranging from minutes to days.

Scientific goals include discovering and following up supernovae and other explosive transients, tidal disruption events, variable stars, active galactic nuclei, and solar system objects such as asteroids. The project emphasizes rapid data processing and alert dissemination. An automated real-time alert stream streams candidate transients to the community. Public data releases provide access to processed imaging and source catalogs.

ZTF data have supported follow-up campaigns with ground-based and space-based facilities and have contributed to multi-messenger astronomy, including follow-up of events associated with gravitational waves and neutrinos. The project is a major data source for time-domain astronomy and is a stepping stone toward the Vera C. Rubin Observatory's Legacy Survey of Space and Time.