1984 in science

Astronomy and space exploration

• February 7 – Astronauts Bruce McCandless II and Robert L. Stewart make the first untethered space walk.
• The National Radio Astronomy Observatory in the United States converts the 36-foot radio telescope on Kitt Peak to the ARO 12m Radio Telescope.

  Biology

• First known case of Bovine spongiform encephalopathy, in England.
• The enzyme telomerase is discovered by Carol W. Greider and Elizabeth Blackburn in the ciliate Tetrahymena.
• Danish physiologist Steen Willadsen first successfully uses cells from early embryos to clone a mammal by nuclear transfer at the British Agricultural Research Council's Institute of Animal Physiology, Cambridge.

  Chemistry and physics

• Peter Kramer and Dan Shechtman publish their discoveries of what will soon afterwards be named quasicrystals.
• Hiroshi Kobayashi and colleagues announce synthesis of tetrakisborate.

  Computer science

• January 24 – Apple Computer places the Macintosh personal computer on sale in the United States. It will be the first successful PC to use a graphical user interface.
• June 6 – The Tetris tile-matching video game, designed by Alexey Pajitnov, is launched in the Soviet Union.

  History of science

• Robert Gwyn Macfarlane publishes Alexander Fleming: The Man and the Myth.

  Paleontology

• The fossil skeleton of the hominid "Turkana Boy" is discovered in Kenya.

  Physiology and medicine

• February 3 – Dr. John Buster and the research team at Harbor-UCLA Medical Center announce history's first embryo transfer from one woman to another resulting in a live birth.
• April 22 – Dr. Robert Gallo and Margaret Heckler of United States Public Health Service announce the discovery of HTLV-III as the virus that causes AIDS.
• May 10 – Barbara H. Bowman and Oliver Smithies show that variations in haptoglobins are due to genetic polymorphisms.

  Technology

• May 5 – Itaipu Dam in South America begins to generate hydroelectricity.
• July 21 – In Jackson, Michigan, a factory robot crushes a worker against a safety bar in apparently the first robot-related death in the United States.

  Awards

• Nobel Prizes
• * Physics – Carlo Rubbia, Simon van der Meer
• * Chemistry – Robert Bruce Merrifield
• * Medicine – Niels K. Jerne, Georges J. F. Köhler, César Milstein
• Turing Award – Niklaus Wirth

  Births

• May 14 – Mark Zuckerberg, American computer programmer and entrepreneur, co-founder of social media platform Facebook.

  Deaths

• February 21 – Anna Baetjer, American toxicologist.
• April 8 – Pyotr Kapitsa, Russian physicist, Nobel Prize laureate.
• April 15 – Grete Hermann, German mathematician and philosopher
• May 13 – Stanislaw Ulam, Polish American mathematician.
• May 24 – Sir Stanley Hooker, English aeronautical engineer.
• August 6 – Abraham Lilienfeld, American epidemiologist.
• August 11 – George Streisinger, Hungarian American molecular biologist, the first person to clone a vertebrate.
• October 20 – Paul Dirac, English-born physicist.
• November 20 – Charles C. Conley, American mathematician working on dynamical systems.
• December 20 – Stanley Milgram, American social psychologist.