Traditional error budgets that characterize pointing capability in terms of a single radial angle lack sufficient information to support analysis of pointing error in terms of distance along a nearby surface.
This work characterizes all sources of angular pointing error in terms of the traditional radial angle, plus a distance from the source of the error to the surface. Translational errors (which don’t apply for celestial pointing distances) were added to the error budget.
The novelty here is the introduction of the concept of an “effective origin of error” and inclusion of translational error, and the derivation of a new mathematical formulation. This innovation is useful for calculating error for any spacecraft pointing at a nearby surface.
This work was done by Stephen F. Peters of Caltech for NASA’s Jet Propulsion Laboratory. This software is available for license through the Jet Propulsion Laboratory, and you may request a license at: https://download. jpl.nasa.gov/ops/request/request_introduction.cfm . NPO-49661