8.5.3 STIS Coordinate Systems

STIS is located off-axis in the focal plane of HST. This article shows how the detector reference frame compares to HST's U2, U3 reference frame.

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Format definitions

Boldface type indicates the name of an APT parameter or a value for a parameter.

(red star) Black text indicates an important note.

Magenta text indicates available but unsupported parameters (requires prior approval from STScI).

Red text indicates restricted parameters (for STScI use only).

Brown text indicates text file parameters.

Items in brackets - <value> - are required values.

Items in square brackets - [<value>] - are optional.


Knowledge of the STIS coordinate system relative to the spacecraft coordinate system is necessary to use the POSition TARGet <X-value>,<Y-value> Special Requirement properly. The figure below shows the sense of the U2 and U3 axes for the various STIS apertures. For more information see the The STIS Instrument Handbook.

Figure 8.1: STIS Coordinate System


Related Links

8.5.1 STIS Central Wavelengths
8.5.2 STIS Internal Calibration Targets
8.5.4 The Official STIS Aperture List



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Change Log

Version Cycle 31 June 2023

          Added link to the STIS IHB