Assertion: probe | /r/HasProperty | launched by the soviet union
Facets:
value: to study its moons
type: PURPOSE
value: to study mars
type: PURPOSE
Source sentences:
text: The Phobos (Russian: Фобос, Fobos, Greek: Φόβος) program was an unmanned space mission consisting of two probes launched by the Soviet Union to study Mars and its moons Phobos and Deimos.