Chapman, when asked shortly before his death which work he had undertaken since retiring he had found most interesting, replied that it was his work on thermal diffusion in highly ionised gases, his work on magnetic storms, his work on instability along magnetic neutral lines, and his work on noctilucent clouds.
Magtitingi, kapag tinanong sa ilang sandali bago ang kanyang kamatayan sa trabaho kung saan siya ay nagtangka dahil mahiyain niya natagpuan ang pinaka-kagiliw-giliw, tumugon na ito ay ang kanyang trabaho sa mainit pagsasabog sa mataas na ionised gases, ang kanyang trabaho sa batubalani storms, ang kanyang trabaho sa katatagan kasama batubalani walang linya, at ang kanyang trabaho sa noctilucent Ulap.