Assertion: proper motion | /r/HasProperty | noted by edmund halley
Facets:
value: for three bright stars
type: PURPOSE
value: in 1718
type: TEMPORAL
Source sentences:
text: Proper motions were first noted by Edmund Halley in 1718 for three bright stars: Sirius, Aldebaran, and Arcturus, by comparing his measurements of their positions to those of Hipparchus of Rhodes (300BC).