pTF

PTF, in the context of astronomy, stands for the Palomar Transient Factory, a time-domain astronomical survey conducted at Palomar Observatory in California. Initiated around 2009, the project used the 48-inch Samuel Oschin telescope equipped with a wide-field imaging camera to search for transient optical phenomena on timescales from hours to years. The goal was to build a catalog of transient events such as supernovae, variable stars, and active galactic nuclei flares, and to provide rapid alerts to the astronomical community to enable follow-up observations.

During its initial phase, the Palomar Transient Factory produced thousands of transient discoveries and light curves, contributing to advances in the study of stellar explosions and other dynamic processes. In 2012 the program evolved into the intermediate Palomar Transient Facility (iPTF), which operated from 2013 to 2017 with an upgraded camera and observing cadence, further expanding the discovery rate and the data repository.

Since 2018, the hosting program’s successor project has been the Zwicky Transient Facility (ZTF), which uses the same site and a newer camera to increase sky coverage and cadence. The PTF/iPTF heritage has influenced contemporary time-domain astronomy by demonstrating the effectiveness of wide-field, high-cadence surveys and by establishing data pipelines and alert networks that support subsequent surveys.

In a broader sense, PTF remains a widely recognized acronym in astronomy for this survey, and its successor projects continue to shape how transient celestial events are discovered and studied.