2012 – Sandy Hook Elementary School shooting: Twenty-eight people, including the gunman, are killed in Sandy Hook, Connecticut.

1948 – Thomas T. Goldsmith Jr. and Estle Ray Mann are granted a patent for their cathode-ray tube amusement device, the earliest known interactive electronic game.

1940 – Plutonium (specifically Pu-238) is first isolated at Berkeley, California.

1972 – Apollo program: Eugene Cernan and Harrison Schmitt begin the third and final extra-vehicular activity (EVA) or "Moonwalk" of Apollo 17. To date they are the last humans to set foot on the Moon.

1962 – NASA launches Relay 1, the first active repeater communications satellite in orbit.

1935 – The Lebensborn Project, a Nazi reproduction program, is founded by Heinrich Himmler.

2020 – The Food and Drug Administration issues an Emergency Use Authorization on the Pfizer–BioNTech COVID-19 vaccine, the first COVID-19 vaccine to be approved by the agency.

1901 – Guglielmo Marconi transmits the first transatlantic radio signal from Poldhu, Cornwall, England to Saint John's, Newfoundland.

1768 – The first edition of the Encyclopædia Britannica is published.

1979 – The eradication of the smallpox virus is certified, making smallpox the first of only two diseases that have been driven to extinction (with rinderpest in 2011 being the other).

1968 – Douglas Engelbart gave what became known as "The Mother of All Demos", publicly debuting the computer mouse, hypertext, and the bit-mapped graphical user interface using the oN-Line System (NLS).

2019 – First confirmed case of COVID-19 in China.

1980 – John Lennon is murdered by Mark David Chapman in front of The Dakota in New York City.

World War II became real to many Americans on Sunday, Dec. 7, 1941, when 350 Japanese planes staged two air attacks on the U. S. military in Pearl Harbor and surrounding bases on Oahu, Hawaii. The attacks that morning took the U.S. Armed Forces by complete surprise.

1932 – German-born Swiss physicist Albert Einstein is granted an American visa.

2006 – NASA reveals photographs taken by Mars Global Surveyor suggesting the presence of liquid water on Mars.

1971 – During a concert by Frank Zappa and The Mothers of Invention at the Montreux Casino, an audience member fires a flare gun into the ceiling, causing a fire that destroys the venue. The incident served as the inspiration for Deep Purple's 1973 song Smoke on the Water.

1997 – In Ottawa, Ontario, Canada, representatives from 121 countries sign the Ottawa Treaty prohibiting manufacture and deployment of anti-personnel landmines. The United States, People's Republic of China, and Russia do not sign the treaty, however.

1992 – A test engineer for Sema Group uses a personal computer to send the world's first text message via the Vodafone network to the phone of a colleague.