Exoplanet transit ephemeris generator, mostly a Franken-script from pieces of OSCAAR
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A Pythonic transiting exoplanet ephemeris generator by Brett Morris (UW) for undergraduate observations from the Manastash Ridge Observatory (MRO). Requirements include numpy, PyEphem, and astropy. These scripts are largely lifted from OSCAAR, and make use of exoplanet data from exoplanets.org.

The transit time predictions are likely accurate to within an hour -- those transit events with the oldest references likely have the most inaccurate transit time predictions.

To run transitephem, clone this repository, change directories into it, edit the mro.par file which contains your observing parameters, and execute the script with

$ git clone https://github.com/bmorris3/transitephem.git
$ cd transitephem
$ python transitephem.py


The observatory parameters are set in the raw text file mro.par, and have the following keywords and value formats:

  • name: string, name of the observatory
  • latitude: observatory latitude; format = deg:min:sec
  • longitude: observatory longitude; format = deg:min:sec
  • elevation: observatory elevation in meters
  • temperature: air temperature in degrees C
  • min_horizon: the pointing limit of your telescope in degrees above the horizon; format = deg:min:sec
  • start_date: start time in UT of the ephemeris; format = (YYYY,MM,DD,hh,mm,ss)
  • end_date: end time in UT of the ephemeris; format = (YYYY,MM,DD,hh,mm,ss)
  • mag_limit: the magnitude of the faintest exoplanet host star that you would like listed in the ephemeris
  • depth_limit: the lower limit on the depth of transit that you would like listed in the ephemeris, in units of millimag
  • calc_transits: calculate ephemeris for transit events; format = boolean
  • calc_eclipses: calculate ephemeris for secondary eclipse events; format = boolean
  • html_out: save HTML output; format = boolean
  • text_out: save CSV output; format = boolean
  • twilight: altitude of the sun in degrees at "twilight", i.e. civil (-6), nautical (-12) or astronomical (-18) twilight; format = float (default = -6)
  • band: default observing band (used for selection by the mag_limit keyword); options = V or K