For a given observation with RXTE's science (x-axis) pointing at the source, the Y and Z rocking axes depend on the spacecraft's roll angle, which is defined and constrained relative to the Sun. The resulting HEXTE clusters' background positions on the sky therefore depend on the date of the observation.
HEXTErock is a software tool provided by the
HEXTE instrument team which will calculate these positions for you. The most
recent HEXTErock software (written in C) is available for download via anonymous
ftp. HEXTErock can also be run by using the form below, which will
produce a sky plot showing the HEXTE clusters' fields of view, together with
x-ray sources from the RXTE All
Sky Monitor catalog.
Note that RXTE cannot observe sources within 30 degrees of the Sun, so those
planning RXTE observations should first use the HEASARC tool VIEWING
to determine the permissible ranges of observing dates for their
source.

High Energy X-ray Timing Experiment