Quantity reigns in this sense. E.g. Venus has a similar gravity as Earth (though a bit less), but the atmosphere is 93 times more dense at "sea level". One of

Quantity reigns in this sense. E.g. Venus has a similar gravity as Earth (though a bit less), but the atmosphere is 93 times more dense at "sea level". One of the theories for why Earth doesn't have a similarly dense atmosphere is because we have the Moon - a large gravitational body nearby strips away the atmosphere enough to prevent the endless buildup like Venus has.