Observing distant Solar System objects with James Webb SpaceTelescope (JWST)

摘要

The James Webb Space Telescope will provide a unique capability to observe Solar System objects such as Kuiper Belt Objects, comets, asteroids, and the outer planets and their moons in the near and mid-infrared. A recent study developed the conceptual design for a capability to track and observe these objects. In this paper, we describe how the requirements and operations concept were derived from the scientific goals and were distributed among the Observatory and Ground Segment components in order to remain consistent with the current event-driven operations concept of JWST. In the event-driven operations concept, the Ground Segment produces a high-level Observation Plan that is interpreted by onboard scripts to generate commands and monitor telemetry responses. This approach allows efficient and flexible execution of planned observations; precise or conservative timing models are not required, and observations may be skipped if guide star or target acquisition fails. The efficiency of this approach depends upon most observations having large time intervals in which they can execute. Solar System objects require a specification of how to track the object with the Observatory, and a guide star that remains within the field of view of the guider during the observation. We describe how tracking and guiding will be handled with JWST to retain the efficient and flexible execution characteristics of event-driven operations. We also describe how the implementation is distributed between the Spacecraft, Fine Guidance Sensor, On-board Scripts, and Proposal Planning Subsystem, preserving the JWST operations concept.