Vastness n. : The quality or state of being vast.

Example:
What are the masses of the gases in the Vastness of space?

Taxonomy
vastness, dictionary, encyclopedia, Synonyms, stn, extent, thesaurus browser, online dictionary, antonyms, enormity, Translations, Free Online Dictionary, English dictionary, largeness, Västra, Västra Frölunda, free online English dictionary, law.

Defination from the web:
vastness in the Online Dictionary. Meaning of vastness. Pronunciation of vastness. Translations of vastness. vastness synonyms, vastness antonyms. ... enormity - vastness of size or extent; "in careful usage the noun enormity is not used to express the idea of great ...