SkyMapper Main Survey

Abstract

Most of SkyMapper's observing time is now dedicated to the Main Survey. The survey scheduler aims to finish a field mostly within one moon period. A first visit in dark conditions establishes a colour sequence with all six bands observed in the space of 20 minutes. Further visits in subsequent nights under dark or grey sky conditions add exposure pairs in g- and r-band, while in grey or bright conditions pairs in i- and z-band are added. A second colour sequence in dark conditions finishes the set. Further pairs in i- and z-band are also observed during astronomical twilight. These twilight observations may be separated by many months from the night-time visits.