1840–1845 Magnetic observatories at Harvard and Girard College
1860 Coast Survey begins regular magnetic observations at Maine's Fort Sullivan, Tift's Observatory in Florida and others
1882–1883 First International Polar Year
1901–1956 United States Coast and Geodetic Survey operates Cheltenham Magnetic Observatory in Maryland
1905–1918 USC&GS Explorer performs magnetic surveys
1909 Carnegie wooden survey ship built for Carnegie Institution for Science begins seven cruises to measure the Earth's magnetic field
1932–1933 Second International Polar Year
1956 Fredericksburg Magnetic Observatory in Virginia replaces Cheltenham^[2]
1957–1958 International Geophysical Year
1961 Boulder Geomagnetic Observatory, Colorado
1973 NOAA/USC&GS geomagnetism program transferred to the USGS
1979–1980 Magsat satellite survey from orbit
1994 U.S. National Space Weather Program (NSWP), an interagency collaboration^[3]

History

See also