Mercury. The smallest and the closest planet to our sun.
Mercury's atmosphere is very thin. The atmosphere of Mercury is mainly made out of sodium. Mercury's atmosphere is so thin because the gases that were there before all got boiled by the sun.
An atmosphere is a region of gases surrounding a planet or other body in space.
gas
atmoshpere
the air around the earth
atmoshpere
lithosphere hydroshpere atmoshpere
TROPOSPHERE, STRATOSPHERE, MESOSPHERE, and THERMOSPHERE
This gas is oxygen.
gravity
pluto's atmoshpere