In 1982, in the first operation of its kind, doctors at the University of Utah Medical Center implanted a permanent artificial heart in the chest of retired dentist Dr. Barney Clark, who lived 112 days with the device.
1823: President James Monroe outlined his doctrine opposing European expansion in the Western Hemisphere.
1939: New York Municipal Airport-LaGuardia Field (later LaGuardia Airport) went into operation as an airliner from Chicago landed at one minute past midnight.
1970: The newly created Environmental Protection Agency opened its doors; its first director was William D. Ruckelshaus.
1995: NASA launched the Solar and Heliospheric Observatory (SOHO), a joint project of the United States and the European Space Agency, on a $1 billion mission to study the sun and interplanetary space; since then, SOHO has discovered 3,000 comets.