Assertion: mercury | /r/CapableOf | compose of helium
Facets:
value: chiefly
type: DEGREE
Source sentences:
text: Mercury has a weak magnetic field and a trace of atmosphere (one-trillionth the density of the Earth and composed chiefly of argon, neon and helium).
text: Instruments on Mariner 10 discovered that Mercury has a weak magnetic field and a trace of atmosphere - a trillionth the density of Earth's atmosphere and composed chiefly of argon, neon and helium.