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Single Star Guiding Information

In some cases, the Guide Star Acquisition process can only acquire a single guide star. In that case, there may be some degree of drift in roll which can happen over time. The degree can vary depending on factors such as the length of the exposure, time of an exposure or set of exposures, and the distance between the target and the guide star in the focal plane. This general principle applies to all instruments in the focal plane. For instrument-specific examples, see below.

Instrument-Specific Examples


HST Help Desk 

Please contact the HST Help Desk with any questions.