Assertion: sunspot | /r/HasProperty | observed by frisian astronomers johannes
Facets:
value: telescopically
type: MANNER
value: in late 1610
type: TEMPORAL
Source sentences:
text: Sunspots were first observed telescopically in late 1610 by English astronomer Thomas Harriot and Frisian astronomers Johannes and David Fabricius, who published a description in June 1611.