A Primitive solar Atmosphere around The young Earth?

The existence of an atmosphere enriched in H and He around the Earth as it formed has often been proposed.

One hypothesis suggests that it could have been captured from the gas present in the proto-planetary disk, before its evaporation.

Subsequently, a secondary atmosphere would have been degassed or brought in by a late veneer of chondritic/cometary material.

Although this model is regularly evoked using giant planets for comparison, there is no geological proof for its existence, except possibly for the neon in the Earth's mantle. While the model has a flaw (mainly relating to chronology, as the gas from the disk is lost in