ANTARES, Arizona–NOIRLab Temporal Analysis and Response to Events System, is a software tool built at NOIRLab to process information about changing objects in the night sky. Large-scale astronomical surveys can obtain images of the sky and compare them to earlier reference images. These comparisons reveal all the objects that have changed in brightness (such as variable or explosive stars) or position (such as asteroids). There are so many moving and variable objects that modern surveys can find hundreds of thousands or millions per night (referred to as alerts), much more than individual astronomers can sort through. ANTARES currently processes the public alert stream from the Zwicky Transient Facility. The upcoming Legacy Survey of Space and Time, operated by the Vera C. Rubin Observatory, will provide an alert stream a hundred times larger and ANTARES will scale up to process it as well.
ANTARES takes the notifications of these changes and filters them in real time using information from the discovery (such as how much the brightness has changed) in addition to cataloged data stored within ANTARES (such as the nature of a host galaxy). These filters are written in Python and users can submit their own. Once subsets of candidate objects are identified by the filters, ANTARES provides data streams that can be transmitted to anyone interested. In addition, users can upload lists of favorite objects and be notified directly when something happens to one of them. ANTARES has a powerful search engine, allowing users to find objects that match their interests, much like Google for the night sky. The ANTARES project is supported by the National Science Foundation and the Heising-Simons Foundation.