The Smithsonian Astrophysical Observatory, founded in Washington, D.C., in 1890 by Samuel Pierpont Langley, began with the focused mission of measuring the Sun’s heat. Under Charles Greeley Abbot, it carried out daily solar observations that refined the solar constant and identified solar variability. In 1955 its scientific headquarters moved to Cambridge, Massachusetts, where affiliation with the Harvard College Observatory broadened its work. After Sputnik, it built a worldwide satellite-tracking network with the United States Air Force and expanded into orbiting observatories, ground-based telescopes, laboratory and theoretical astrophysics, and computing. Since 1973 it has been part of the Center for Astrophysics | Harvard & Smithsonian.

Cambridge, Massachusetts · USA