Activity

The Moon, About 4 Billion Years Ago, Had An Atmosphere That Lasted For Only 70 Million Years. And This Was Determine From The Gaseous Composition Of The Volcanic Moon Rock Samples Brought Back From The Apollo Mission, And Via Calculation Of How Much Of These Gaseous Compositions Rose To Form The Atmosphere.

It Turns Out That Our Moon Once Had an Atmosphere

https://futurism.com/moon-atmosphere-apollo-missions/

The atmosphere was thickest during the peak in volcanic activity about 3.5 billion years ago and, when created, would have persisted for about 70 million years before being lost to space.