RA/Dec/PA Offset Calculator

Input Form

This tool will compute the arcsecond offsets (east and north) between two sky positions, and the relative bearing as well. It is useful for obtaining telescope offsets and also for deriving slit position angles. Simply enter a pair of Right Ascension and Declination values in the entry boxes below and click Compute. Valid formats are:
  • Space-separated (HH MM SS.SSS)
  • Colon-separated (HH:MM:SS.SSS)

Position R.A. Dec
Position 1:
Position 2:
Last modified: 03/31/2025 06:14
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