vocabulary Astronomy
;
/*
* Value Types */
AstronomicalObject Code is written as String(12); Mass is written as Real(32); Moon Name is written as String(256); Nr Days is written as Real(32); Planet Name is written as String(256);
/*
* Entity Types */
AstronomicalObject is identified by its Code; AstronomicalObject has at most one Mass;
Moon is a kind of AstronomicalObject identified by its Name;
Orbit is where
AstronomicalObject is in orbit;
Orbit is around one AstronomicalObject (as Center) /* [acyclic, stronglyintransitive] */; Orbit has a synodic period of at most one Nr Days;
Planet is a kind of AstronomicalObject identified by its Name;
Star is a kind of AstronomicalObject;
/*
* Constraints: */
for each AstronomicalObject exactly one of these holds:
AstronomicalObject is a Star, AstronomicalObject is a Planet, AstronomicalObject is a Moon;