astroplan is an open source Python package to help astronomers plan observations.

The goal of astroplan is to make a flexible toolbox for observation planning and scheduling. When complete, the goal is to be easy for Python beginners and new observers to to pick up, but powerful enough for observatories preparing nightly and long-term schedules.


  • Calculate rise/set/meridian transit times, alt/az positions for targets at observatories anywhere on Earth

  • Built-in plotting convenience functions for standard observation planning plots (airmass, parallactic angle, sky maps).

  • Determining observability of sets of targets given an arbitrary set of constraints (i.e., altitude, airmass, moon separation/illumination, etc.).

  • astropy powered!




If you use astroplan in your work, please cite Morris et al. 2018:

       author = {{Morris}, Brett M. and {Tollerud}, Erik and {Sip{\H{o}}cz}, Brigitta and {Deil}, Christoph and {Douglas}, Stephanie T. and {Berlanga Medina}, Jazmin and {Vyhmeister}, Karl and {Smith}, Toby R. and {Littlefair}, Stuart and {Price-Whelan}, Adrian M. and {Gee}, Wilfred T. and {Jeschke}, Eric},
        title = "{astroplan: An Open Source Observation Planning Package in Python}",
      journal = {\aj},
     keywords = {methods: numerical, methods: observational, Astrophysics - Instrumentation and Methods for Astrophysics},
         year = 2018,
        month = mar,
       volume = {155},
       number = {3},
          eid = {128},
        pages = {128},
          doi = {10.3847/1538-3881/aaa47e},
archivePrefix = {arXiv},
       eprint = {1712.09631},
 primaryClass = {astro-ph.IM},
       adsurl = {},
      adsnote = {Provided by the SAO/NASA Astrophysics Data System}