Package nightfall

Nightfall is an astronomy application for emulation of eclipsing stars

http://www.hs.uni-hamburg.de/DE/Ins/Per/Wichmann/Nightfall.html

Nightfall is an astronomy application for fun, education, and science.
It can produce animated views of eclipsing binary stars,
calculate synthetic lightcurves and radial velocity curves,
and eventually determine the best-fit model for a given set of
observational data of an eclipsing binary star system.
It is, however, not able to fry your breakfast egg on your harddisk.

General Commands
Command Description
nightfall binary star astronomy