Assertion: robotic spacecraft | /r/CapableOf | begin observing mars
Facets:
value: with launching mariner
type: OTHER
value: in the 1960s
type: TEMPORAL
Source sentences:
text: Robotic spacecraft began observing Mars in the 1960s, with the United States launching Mariner 4 in 1964 and Mariners 6 and 7 in 1969.