1781 – William Herschel discovers Uranus.

1981 – After 19 years of presenting the CBS Evening News, Walter Cronkite signs off for the last time.

1966 – Venera 3 Soviet space probe crashes on Venus becoming the first spacecraft to land on another planet's surface.

1961 – United States President John F. Kennedy establishes the Peace Corps.

1941 – W47NV begins operations in Nashville, Tennessee becoming the first FM radio station in the U.S..

1893 – Electrical engineer Nikola Tesla gives the first public demonstration of radio in St. Louis, Missouri.

1872 – Yellowstone National Park is established as the world's first national park.

1692 – Sarah Good, Sarah Osborne and Tituba are brought before local magistrates in Salem Village, Massachusetts, beginning what would become known as the Salem witch trials.

1993 – Bureau of Alcohol, Tobacco and Firearms agents raid the Branch Davidian church in Waco, Texas with a warrant to arrest the group's leader David Koresh. Four BATF agents and five Davidians die in the initial raid, starting a 51-day standoff.

1983 – The final episode of M*A*S*H airs, with almost 106 million viewers. It still holds the record for the highest viewership of a season finale.

1953 – James Watson and Francis Crick announce to friends that they have determined the chemical structure of DNA; the formal announcement takes place on April 25 following publication in April's Nature (pub. April 2).

1928 – C. V. Raman discovers Raman scattering.



Oh... raman. Sorry. 

1525 – The Aztec king Cuauhtémoc is executed by Hernán Cortés's forces.

1942 – The Battle of Los Angeles, one of the largest documented UFO sightings in history; the event lasted into the early hours of February 25.

 aflanigan wrote: 

 Red_Dragon wrote: 
Are you sure?

1954 – The first mass inoculation of children against polio with the Salk vaccine begins in Pittsburgh.

1927 – German theoretical physicist Werner Heisenberg writes a letter to fellow physicist Wolfgang Pauli, in which he describes his uncertainty principle for the first time.

1896 – The Tootsie Roll is invented.

2013 – The smallest extrasolar planet, Kepler-37b is discovered.