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

1995 – The United States Food and Drug Administration approves Saquinavir, the first protease inhibitor to treat HIV/AIDS. Within 2 years of its approval, annual deaths from AIDS in the United States fall from over 50,000 to approximately 18,000.

1969 – Altamont Free Concert: At a free concert performed by the Rolling Stones, eighteen-year old Meredith Hunter is stabbed to death by Hells Angels security guards.

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.

1956 – The Million Dollar Quartet (Elvis Presley, Jerry Lee Lewis, Carl Perkins, and Johnny Cash) get together at Sun Studio for the first and last time.

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.

1938 – Nazi Germany issues the Decree on the Utilization of Jewish Property forcing Jews to sell real property, businesses, and stocks at below market value as part of Aryanization.

1988 – Benazir Bhutto is sworn in as Prime Minister of Pakistan, becoming the first woman to head the government of a Muslim-majority state.

1970 – The United States Environmental Protection Agency begins operations.

1942 – World War II: During the Manhattan Project, a team led by Enrico Fermi initiates the first artificial self-sustaining nuclear chain reaction.

1766 – Swedish parliament approves the Swedish Freedom of the Press Act and implements it as a ground law, thus being first in the world with freedom of speech.

1955 – American Civil Rights Movement: In Montgomery, Alabama, seamstress Rosa Parks refuses to give up her bus seat to a white man and is arrested for violating the city's racial segregation laws, an incident which leads to that city's bus boycott.

1952 – The New York Daily News reports the news of Christine Jorgensen, the first notable case of sex reassignment surgery.

1878 – President Rutherford B. Hayes gets the first telephone installed in the White House.

1487 - The first German Beer Purity Law (Reinheitsgebot) is promulgated in Munich by Albert IV, Duke of Bavaria, stating that beer should be brewed from only three ingredients: water, malt, and hops

1982 – Michael Jackson releases Thriller, the best-selling music album of all time.

1972 – Atari releases Pong, the first commercially successful video game.

1963 – "I Want to Hold Your Hand", recorded on October 17, 1963, is released by the Beatles in the United Kingdom.