Kosmorrolib Documentation


An astronomical object (a.k.a aster)


class Object:
    identifier: ObjectIdentifier,
    skyfield_name: str,
    radius: float = None


The Object class is an abstract class. Use one of the following children classes instead:

  • Star
  • Planet
  • DwarfPlanet (extends Planet)
  • Satellite

Those classes have exactly the same properties and methods as the Object class.


  • identifier: an unique identifier to know what object it is exactly (Mercury, Venus, etc.)
  • skyfield_name: the name of the corresponding object in Skyfield library - used internally
  • radius: the object's radius. Used to detect some events, e.g. occultations


get_type(self) -> ObjectType

Returns the kind of aster the object is representing: a planet, a satellite, etc.

get_apparent_radius(self, for_date: Union[Time, datetime]) -> Angle

Calculate the apparent radius, in degrees, of the object from the given place at a given time.

  • for_date: the datetime for which the radius must be calculated.


Returns the object as a plain simple Python dictionnary.

See also

Help us to improve this page, contribute to the documentation!