Synonyms that are in the dictionary are marked in green. Synonyms that are not in the dictionary are marked in red.
Antonyms that are in the dictionary are marked in green. Antonyms that are not in the dictionary are marked in red.
All three of these gasses are present in comets and all three are what is known as hypervolatiles.
Source: https://time.com/6265071/oumuamua-spacecraft-comet-mystery/