* Yaron Minsky is the main author

* Sandor Lehoczky helped out in implementing planet bouncing

* Gunner Poulsen <gp@lyngbjerggaardskolen.dk> provided a number of useful
  suggestions, as well as a Danish translation.

* Daniel Andor contributed the 4th-order runge-kutta code

* Martin Pitt contributed many packaging fixes while building a debian
  package, and also wrote the initial version of the manpage.