Science operations with the James Webb Space Telescope

The James Webb Space Telescope (JWST) will be a powerful space observatory whose four science instruments will deliver rich imaging and multiplexed spectroscopic datasets to the astronomical and planetary science communities. The ground segment for JWST, now being designed and built, will carry out JWST's science operations. The ground segment includes: software that the scientific community will use to propose and specify new observations; systems that will schedule science and calibration observations in a way that respects physical and investigator-specified constraints, while satisfying preferences for efficient observing, low background levels, and distributed subscription across a year; the infrastructure to regularly measure and maintain the telescope's wavefront; orbit determination, ranging, and tracking; communication via the Deep Space Network to command the observatory and retrieve scientific data; onboard scripts that execute each observing program in an event-driven fashion, with occasional interruptions for targets of opportunity or time-critical observations; and a system that processes and calibrates the data into science-ready products, automatically recalibrates when calibrations improve, and archives the data for timely access by the principal investigator and later worldwide access by the scientific community. This ground system builds on experience from operating the Hubble Space Telescope, while solving challenges that are unique to JWST. In this paper, we describe the elements of the JWST ground system, how it will work operationally from the perspective of the observatory itself, and how a typical user will interact with the system to turn their idea into scientific discovery.