The 4MOST Operations System

The 4MOST multi-object spectroscopic instrument (to be mounted on the ESO/VISTA telescope) will be used to conduct an ambitious multi-year wide area sky survey. A disparate set of science goals, requiring observation of tens of millions of galactic and extragalactic targets, must be satisfied by a unified program of observations. The 4MOST Operations System is designed to facilitate this complex task by i) providing sophisticated simulation tools that allow the science team to plan and optimise the 4MOST survey, ii) carrying out optimised mediumterm scheduling using survey forecasting tools and feedback from previous observations, and iii) producing sets of observation blocks ready for execution at the telescope. We present an overview of the Operations System, highlighting the advanced facility simulator tool and the novel strategies that will enable 4MOST to achieve its challenging science goals.