Assertion: argon | /r/AtLocation | earth's atmosphere
Facets:
Source sentences:
text: The argon that exists in earth's atmosphere is argon-40, and is heavier than the argon that exists in most of the universe, which is argon-36, and is formed from stellar nucleosynthesis.
text: Argon is found in the Earth's atmosphere; it is also present in some potassium minerals due to the radioactive decay of isotope potassium-40.