What gases exist in outer space?

Outer space contains a variety of gases, primarily hydrogen and helium, which together account for about 98% of the observable universe. Trace amounts of other gases, such as carbon dioxide, methane, ammonia, and nitrogen, can also be found, particularly in regions like molecular clouds. Additionally, ionized gases, or plasma, are prevalent in stellar environments and around celestial bodies. These gases play crucial roles in the formation of stars and galaxies.