computeUTForElevation

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For a specified RA/Dec, date/MJD, and elevation, compute the UT time that the object will cross that point (by repeatedly calling computeAzElFromRADecMJD). It also converts this time to local Chilean time using the python pytz module, which accounts for daylight savings time changes in Chile. See also computeAzElFromRADecLST.

Usage:

au.computeUTForElevation(elevation, radec=None, date='', mjd=0, observatory='ALMA', intervalMinutes=5, vis=None, field=None, useJPL=False)
  • elevation: in degrees
  • raDec: if specified, it must either be a tuple in radians: [ra,dec], or a string of the form "hh:mm:ss.sss -dd:mm:ss.ss"
  • mjd: modified Julian date (optional, default = today)
  • date: string date (optional), Either of these formats is valid: 2011/10/15, 2011-10-15
  • observatory: location to run the calculation for
  • intervalMinutes: grid size to use in the search (reduce for higher accuracy & longer computation time)
  • vis: the measurement set from which to read the field coordinates
  • field: the field ID or name in the measurement set to use, or the name of a planet
  • useJPL: if True, query JPL Horizons for planets instead of casa ephemerides

Example:

CASA <4>: au.computeUTForElevation(30, '09:47:33 +11:25:43', date='2013-06-01')
 rising: 18:15 = 14:14 Chile time
setting: 01:00 = 20:59 Chile time

CASA <11>: au.computeUTForElevation(30, field='Uranus',date='2014-04-26')
Since vis has not been specified, I will assume that Uranus is a planet.
Converted MJD=56773.000000 to 2014-04-26 00:00:00 UT
Using casa's ephemerides for Uranus. These are in J2000 coordinates in this casa version (>=4.0.0)
J2000 Position: 00:51:04.25760, +004:46:11.49600   Azim, Elev: -104.483, -41.407
 rising: 11:25 UT  = 08:24 Chile time
setting: 18:40 UT  = 15:39 Chile time

-- ToddHunter - 2013-11-06

This topic: Main > TWikiUsers > ToddHunter > CasaExtensions > ComputeUTForElevation
Topic revision: 2014-08-10, ToddHunter
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