2000

2000 (MM) was a century leap year in the Anno Domini and Common Era designations.

Astronomy

 * May 4 – A rare astronomical conjunction occurs on the New Moon including all seven of the traditional celestial bodies known from ancient times until the discovery of Uranus in 1781; this conjunction consists of the Sun and Moon, Mercury, Venus, Mars, Jupiter and Saturn.
 * August 10 – Publication of the M-sigma relation in The Astrophysical Journal.

Biology

 * June 26 – 'Rough draft' of the human genome is announced jointly by President of the United States Bill Clinton and British Prime Minister Tony Blair.
 * December 14 – The full genome sequence of the flowering plant Arabidopsis thaliana is published in Nature.
 * 10-year Census of Marine Life launched.

Computer science

 * March 4 – Sony Computer Entertainment releases the PlayStation 2 sixth generation home video game console in Japan.
 * March 14 – Stephen King's horror story Riding the Bullet is published in e-book format only, the world's first mass-market electronic book.

Earth Science

 * March – Iceberg B-15, with a surface area of 11,000 km2 (4,200 sq mi), calves from the Ross Ice Shelf of Antarctica.
 * April – Cave of the Crystals discovered at the Naica Mine in Mexico.

Medicine

 * January 31 – English doctor Harold Shipman is found guilty of killing fifteen of his elderly patients by lethal injections of diamorphine, the only British physician ever convicted of murdering his patients; he is actually considered to have killed at least 215.

Paleontology

 * First fossil of Orrorin, an early species of Homininae, discovered in the Tugen Hills of Kenya.

Awards

 * Nobel Prizes
 * Physics – Zhores Alferov, Herbert Kroemer - Jack Kilby
 * Chemistry – Alan J Heeger, Alan G MacDiarmid, Hideki Shirakawa
 * Medicine – Arvid Carlsson, Paul Greengard, Eric R. Kandel
 * Turing Award: Andrew Yao
 * Wollaston Medal for Geology: William Sefton Fyfe

Deaths

 * January 12 – Margaret Hutchinson Rousseau (b. 1910), American chemical engineer.
 * January 19 – G. Ledyard Stebbins (b. 1906), American botanist and geneticist.
 * March 7 – W. D. Hamilton (b. 1936), English evolutionary biologist, widely recognised as one of the greatest evolutionary theorists of the 20th century.
 * March 10 – Nim Chimpsky (b. 1973), chimpanzee
 * May 6 – John Clive Ward (b. 1924), English-born physicist
 * May 19 – Yevgeny Khrunov (b. 1933), cosmonaut
 * June 14 – Elsie Widdowson (b. 1908), English nutritionist
 * July 8 – W. David Kingery (b. 1926), American materials scientist specializing in ceramic materials
 * September 20 – Gherman Titov (b. 1935), cosmonaut
 * October 4 – Michael Smith (b. 1932), English-born Canadian chemist, 1993 Nobel Prize winner
 * November 20 – Nikolay Dollezhal (b. 1899), a key figure in Soviet atomic bomb project and chief designer of nuclear reactors.