I have a story set in a far future in which all record of humanity has been lost. A  collective intelligence compiling a history of the universe discovers that, although Sol should have had intelligent life, no record exists that shows it participated in galactic civilization. A collective committee journeys to Sol and finds a museum on the North Pole of the Moon. The Rosetta  Stone that can unlock the mystery of a spacefaring civilization that never achieved interstellar travel is found in an ancient artifact from the dim prehistory of the Hemmen, an intelligent species that arose near Sol.