NAME: etut PURPOSE: (one line only) Compute ET-UT time offset for a given Julian Date DESCRIPTION: CATEGORY: Astronomy CALLING SEQUENCE: ans = etut(jd) INPUTS: jd - Julian Date (UTC), scalar or vector OPTIONAL INPUT PARAMETERS: KEYWORD INPUT PARAMETERS: OUTPUTS: Return value which is the difference of ET-UT for the given JD. KEYWORD OUTPUT PARAMETERS: COMMON BLOCKS: SIDE EFFECTS: RESTRICTIONS: Needs to have access to the file, leapsec.dat. This file is periodically updated as new leap-seconds are announced. This file is contained as part of this library. PROCEDURE: MODIFICATION HISTORY: 2010/12/02, Written by Marc W. Buie based on a routine provided by Larry Wasserman which was in turn adapted from a routine supplied to him by Myles Standish.