Dr. Isaac Hammond was the chief research scientist of the ATLAS Program.
Hammond was devoted to his research at the ATLAS Observatory. Despite making progress in his goals, the Pentagon decided to shut down the project. When the project's Army advisor James Oberlin informed Hammond, he flew into a rage before being restrained by Military Police until he finally calmed down and promptly walked out of the ATLAS Observatory, dismissed from his position.
Five months after the ATLAS program was shut down and the bombs fell, Hammond returned to the observatory and attempted to finish the project, as he believed it would help the post-apocalyptic world. He reactivated the facility's security robots to aid in his work. Hammond did not survive to finish his work and died in the observatory, his skeleton being found in the ATLAS substructure.
At launch, Hammond's skeleton was found in the normal ATLAS Observatory interior, next to ATLAS Research Log #293 and the ATLAS director's password. However, with the Steel Dawn, his skeleton was moved to the ATLAS substructure. Scribe Odessa Valdez will make a comment upon discovering his skeleton in Mother of Invention, wishing to give him a proper burial.
Isaac Hammond's skeleton appears only in Fallout 76.