Assertion: purpose built radio telescope | /r/HasProperty | constructed by radio amateur grote reber
Facets:
value: in 1937
type: TEMPORAL
value: in his back yard in wheaton
type: LOCATION
Source sentences:
text: The first purpose-built radio telescope was a 9-meter parabolic dish constructed by radio amateur Grote Reber in his back yard in Wheaton, Illinois in 1937.