Nitrogen, oxygen, argon (4th carbon dioxide)
The three most common gasses in our atmosphere are: nitrogen 78%, oxygen 21%, and argon <1%.
Atmosphere.
Any gas or group of gases can make a thin atmosphere.
The atmosphere is composed of approximatly 79% Nitrogen - 20% Oxygen - 1% Argon and 'other gasses'
Hydrogen and helium
The gases that make up Uranus' atmosphere is mainly hydrogen, helium, and methane.
Nitrogen and oxygen.
CO2 makes up approximately 0.03% of Earth's atmosphere
The gases that make up Neptune's atmosphere are 80% hydrogen, 19% helium and 1% methane gas.
78% Nitrogen,and 21% Oxygen
The four main gases in Earth's atmosphere are nitrogen (78%), oxygen (21%), argon (0.9%), and carbon dioxide (0.04%). These gases make up the majority of the atmosphere and are essential for supporting life on Earth.
Mercury's weak gravity and close proximity to the hot sun make it easy for gasses to escape.