Astrophysics Exhibit, Conference on the Future of the SI, by Unknown, 1927, Smithsonian Archives - History Div, Astrophysics Exhibit at the Conference on the Future of the Smithsonian Institution on February 11, 1927, with Charles G. Abbot, (left) astrophysicist and fifth Secretary of the Smithsonian (1928-1944) and Loyal B. Aldrich, (right) Research Assistant, standing behind a table..