Usage of ComputeLST

Return to directory of Todd's CASA extensions

Computes the LST (in hours) for a specified time (in MJD seconds or UT on the current date) and longitude. If neither time is specified, it uses the current time. See also ComputeLSTDay.


au.ComputeLST(mjdsec, longitude=-67.7549, ut=None, hms=False, observatory=None, 
       date=None, verbose=False, prec=0)
  • mjdsec: MJD seconds
  • ut: ut time on the current day as a HH:MM:SS string or floating point hours
  • longitude: degrees, where east of Greenwich is positive. Default = ALMA.
  • hms: if True, then return the time as a HH:MM:SS string, instead of floating point hours
  • prec: number of fractional seconds digits to show (if hms=True)
  • observatory: if specified, then ignore the longitude parameter and look up the value in CASA
  • date: a date string, or date/time string. Either of these formats is valid:
    • 2011/10/15 05:00:00
    • 2011/10/15-05:00:00
    • 2011-10-15 05:00:00
    • 2011-10-15T05:00:00
    • 2011-Oct-15T05:00:00


CASA <16>: au.ComputeLST(55600*86400,-67)
  Out[16]: 4.716901142775896
CASA <13>: au.ComputeLST(date='2015-01-17 16:38', hms=True)
  Out[13]: '19:54:07'

-- ToddHunter - 2013-09-09
Topic revision: r5 - 2015-09-08, ToddHunter
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding NRAO Public Wiki? Send feedback