Assertion: planet's orbit | /r/HasProperty | comet
Facets:
value: typically
type: DEGREE
Source sentences:
text: X/ indicating a comet for which no reliable orbit could be calculated (typically comets described in historical chronicles), D/ indicating a comet that has broken up or been lost, and A/ indicating an object at first thought to be a comet but later reclassified as an asteroid (C/2017 U1 became A/2017 U1, then finally 1I/ʻOumuamua).