The Monster reference catalog

The Monster is a whole-sky reference catalog built specifically for calibration of LSST data.

The Monster combines data from multiple previous reference catalogs, including Dark Energy Survey, Pan-STARRS, and Gaia, all transformed to a common system. It contains only stellar sources. No single prior reference catalog had the depth, sky coverage, and bandpasses needed to calibrate LSST data. Both photometric and astrometric calibration make use of The Monster.

For details about how the catalog was created, see “The Monster: A reference catalog with synthetic ugrizy-band fluxes for the Vera C. Rubin observatory” (dmtn-277.lsst.io).