Assertion: known planet | /r/HasProperty | mercury
Facets:
Source sentences:
text: It is a frigid world, billions of kilometres from Earth, and 30 times less massive than the then-smallest known planet, Mercury.
text: According to the IAU’s definition for planet above, there are 8 known planets in the Solar System: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.