from Atmosphere of the Moon - Wikipedia
This drawing is from the crews of Apollo 17 astronauts as they witnessed the sunrise on the Moon's surface. Without atmosphere such phenomenon is impossible. The sun, as it rises over the horizon, would be a perfect disk without any distortion if there is no atmosphere on the Moon.
Even without any volcanic activity, the surface of any sizable heavenly body must have some sort of thin atmosphere made of gas of the same or similar rock/metals/ice surface composition. The reason for an atmosphere, after all, is due to the powerful solar/cosmic rays vibrating at the gamma ray strength, which basically is a perpetual weapon that tears everything apart. It is this force which penetrates and grinds the rocks/ice/metal of a planetary body constantly that results in gas above it. To say that that there's no air on any planetoid larger than Ceres is ludicrous.
Let's say there's breathable air on the Moon at up to 50 meters from the surface. Here on Earth, it is 8,000 meters before you need an oxygen tank. There is substantial gas/air all the way up to 16,000m. But, not all lot of oxygen because O2 is much heavier than N2. Here on Earth, N2 and O2 make up 99% of the atmosphere. O2 is heavier than N2. The climate change fear mongers keep bringing up the danger of CO2 but, Carbon diOxide is less than 0.0415% currently. Keep setting wild fires to kill trees and blame global warming (fires do not get set by themselves especially in dry lightning free weather) and see what really then happens to O2 level. But, I will now come back to the topic in hand.
Oxygen gets released from the surface by gamma rays hitting a planet (rock/metal/ice). Countless rocks contain, you guessed it, oxygen. Do you really think the air composition would be any different at a nearby planet?
Something dawned on me this morning. What would you do if you lived on the surface of the Moon? How would you build a town or a base if there was breathable air only at 0-50m from the surface. Wouldn't you make a crater and set up your village at the bottom of the pit? Now, you have up to 200m of air above you. Remember O2 is heavy. It sits on the surface. The only other common gas that is heavier than O2 is CO2.
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