Jupiter Is Mostly Made of This Gas

This page is the CodyCross answer for the clue below from Amusement Park, Group 204, Puzzle 3 (Happy Boardwalk).

Question is: Jupiter Is Mostly Made of This Gas

and the answer is: HYDROGEN

Word Meaning:

HYDROGEN — (uncountable) The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.008.

Definitions from Wiktionary.

Jupiter is mostly made of this gas — CodyCross Answer | CodyCross Solutions