History of 20 May
- 1990 – The Hubble Space Telescope sent back its first photographs.
- 1993 – The final episode of “Cheers” was aired on NBC-TV.
- 1996 – The U.S. Supreme Court struck down a Colorado measure banning laws that would protect homosexuals from discrimination.
- 1999 – At Heritage High School in Conyers, GA, a 15-year-old student shot and injured six students. He then surrendered to an assistant principal at the school.
- 2010 – Scientists announced that they had created a functional synthetic genome.
- 2010 – Five paintings worth 100 million Euro were stolen from the Musée d’Art Moderne de la Ville de Paris.
- 2012 – At least 27 people are killed and 50 others injured when a 6.0-magnitude earthquake strikes northern Italy.
- 2013 – An EF5 tornado strikes the Oklahoma City suburb of Moore, killing 24 people and injuring 377 others.
- 2019 – The International System of Units (SI): The base units are redefined, making the international prototype of the kilogram obsolete.
Celebrating Birthday Today
- 1981 – Rachel Platten, American singer and songwriter
- 1981 – Lindsay Taylor, American basketball player
- 1981 – Mark Winterbottom, Australian race car driver
- 1982 – Petr Čech, Czech footballer
- 1982 – Imran Farhat, Pakistani cricketer
- 1982 – Jessica Raine, English actress
- 1982 – Daniel Ribeiro, Brazilian director, producer, and screenwriter
- 1983 – Óscar Cardozo, Paraguayan footballer
- 1983 – Matt Langridge, English rower
- 1984 – Mauro Rafael da Silva, Brazilian footballer
- 1984 – Patrick Ewing, Jr., American basketball player
- 1984 – Keith Grennan, American football player
- 1985 – Chris Froome, Kenyan-English cyclist
- 1985 – Brendon Goddard, Australian footballer
- 1986 – Dexter Blackstock, English footballer
- 1986 – Stéphane Mbia, Cameroonian footballer
- 1986 – Jiřina Svobodová, Czech pole vaulter
- 1987 – Mike Havenaar, Japanese footballer
- 1987 – Julian Wright, American basketball player
- 1988 – Joel Moon, Australian rugby league player
- 1989 – Silesia Valve, Australian-Tongan rugby league player
- 1991 – Bastian Baker, Swiss singer, songwriter, and performer
- 1991 – Emre Colak, Turkish footballer
- 1992 – Cate Campbell, Malawian-Australian swimmer
- 1992 – Jack Gleeson, Irish actor
- 1992 – Enes Kanter, Turkish basketball player
- 1993 – Caroline Zhang, American figure skater
- 1996 – Brian Kelly, Australian rugby league player
- 1998 – Jamie Chadwick, English race car driver
- 1998 – Nam Nguyen, Canadian figure skater