The origin, early development and subsequent fate of the their hypothesis is examined in detail in and . Moulton began working with Chamberlin, who was professor of geology at Chicago, when he was undertaking graduate studies at Chicago. Chamberlin correctly realised that the earth was much older than the age proposed by Kelvin which was accepted at that time.
Ang pinagmulan, maagang pag-unlad at kasunod na tadhana ng kanilang mga palagay ay napagmasdan sa mga detalye sa at. Moulton nagsimula nagtatrabaho sa Chamberlin, na noon ay propesor ng heolohiya sa Chicago, kapag siya ay nagtapos sa libing pag-aaral sa Chicago. Chamberlin tama realised na ang lupa ay marami mas matanda kaysa sa edad na iminungkahi ni Kelvin na kung saan ay natanggap sa oras na iyon.