1918 in science

Astronomy

• June 8 – Nova Aquila, the brightest observed since 1604, is discovered.
• Kiyotsugu Hirayama identifies several groups of main belt asteroids, now known as Hirayama families.
• Harlow Shapley demonstrates that globular clusters are arranged in a spheroid or halo whose center is not the Earth, but the center of the galaxy.
• Heber Curtis discovers a relativistic jet of matter emerging from Elliptical galaxy M87.

  Biology

• February 21 – The last known Carolina parakeet dies in Cincinnati Zoo.
• Around 1000 pilot whales strand in the Chatham Islands.
• R. A. Fisher puts forward a genetic model that shows that continuous variation could be the result of Mendelian inheritance in his paper "The Correlation Between Relatives on the Supposition of Mendelian Inheritance".
• J. Henri Fabre's The Sacred Beetle, and others published in English.
• Jacques Loeb's Forced Movements, Tropisms, and Animal Conduct published in the United States.

  Cryptography

• February 23 – Arthur Scherbius applies to patent the Enigma machine.
• Edward Hugh Hebern patents the Hebern rotor machine.

  History of science

• Technisches Museum Wien opens in Vienna.

  Mathematics

• Felix Hausdorff introduces the concept of the fractional Hausdorff dimension.
• Gaston Julia describes the iteration of a rational function.

  Physics

• July 26 – Emmy Noether introduces what becomes known as Noether's theorem, from which conservation laws are deduced for symmetries of angular momentum, linear momentum and energy, at Göttingen, Germany.
• Josef Lense and Hans Thirring find the gravitomagnetic precession of gyroscopes in the equations of general relativity.
• Hans Reissner and Gunnar Nordström solve the Einstein and Maxwell field equations for charged spherically-symmetric non-rotating systems.
• Friedrich Kottler gets a Schwarzschild solution without Einstein vacuum field equations.

  Physiology and medicine

• January – 1918 flu pandemic: "Spanish 'flu" first observed in Haskell County, Kansas.
• March 26 – Dr. Marie Stopes publishes her influential book Married Love in the U.K., following it with Wise Parenthood, a treatise on birth control.
• June–August – "Spanish 'flu" becomes pandemic.
• September 7 – J. B. Christopherson publishes his discovery that antimony potassium tartrate is an effective cure for bilharzia.
• Hartog Jacob Hamburger describes the chloride shift.

  Technology

• April 10 – Alexander M. Nicholson files a United States patent for the radio crystal oscillator.
• Edwin Howard Armstrong develops the superheterodyne receiver.
• George Constantinescu publishes Theory of sonics: a treatise on transmission of power by vibrations, originating the study of this branch of continuum mechanics.
• Theodore von Karman and Asbóth Oszkár build the first co-axial helicopter.
• Charles Strite invents the pop-up toaster.

  Awards

• Nobel Prize
• * Physics – Max Karl Ernst Ludwig Planck
• * Chemistry – Fritz Haber
• * Medicine – not awarded

  Births

• January 23 – Gertrude B. Elion, American pharmacologist, Nobel laureate.
• January 27 – Antonín Mrkos, Czech astronomer.
• March 13 – Marjorie Blamey, English botanical illustrator.
• March 16 – Frederick Reines, American physicist, Nobel laureate.
• April 4 – Joseph Ashbrook, American astronomer.
• April 25 – Gérard de Vaucouleurs, French astronomer.
• May 11 – Richard Feynman, American physicist, Nobel laureate.
• May 20 – Alexandra Illmer Forsythe, American computer scientist
• June 6 – Edwin G. Krebs, American biochemist, Nobel laureate.
• July 15
• * Bertram Brockhouse, Canadian physicist.
• * Brenda Milner, English-born neuropsychologist.
• July 16 – Samuel Victor Perry, English biochemist, pioneer in the field of muscle biochemistry.
• August 3 – Cheng Kaijia, Chinese nuclear physicist.
• August 13 – Frederick Sanger, English molecular biologist, double Nobel laureate.
• August 26 – Katherine Johnson, African American mathematician and space physicist.
• August 29 – John Herivel, British cryptanalyst and science historian.
• September 8 – Derek Barton, English-born organic chemist, Nobel laureate.
• September 27 – Martin Ryle, English radio astronomer.
• October 4 – Adrian Kantrowitz, American cardiac surgeon.
• November 10 – Ernst Otto Fischer, German chemist, Nobel laureate.
• November 19 – Hendrik C. van de Hulst, Dutch astronomer.
• December 25 – Tamara Mikhaylovna Smirnova, Russian astronomer.
• Eleanor C. Pressly, American mathematician and aeronautical engineer.

  Deaths

• January 6 – Georg Cantor, German mathematician.
• January 26 – Ewald Hering, German physiologist.
• January 31 – Ivan Puluj, Austrian-born Ukrainian physicist.
• April 20 – Karl Ferdinand Braun, German physicist, Nobel laureate.
• May 1 – G. K. Gilbert, American geologist.
• May 31 – Alexander Mitscherlich, German chemist.
• June 13 – Samuel Jean de Pozzi, French gynaecologist.
• June 27 – George Mary Searle, American astronomer.
• June 29 – Alfred Senier, Irish chemist.
• September 7 – Peter Ludwig Mejdell Sylow, Norwegian mathematician.
• October 28 – Ulisse Dini, Italian mathematician.
• November 3 – Aleksandr Lyapunov, Russian mathematician and physicist.
• November 29 – Thomas Allinson, English physician and dietetic reformer.
• December 26 – William Hampton Patton, American entomologist.
• December 27 – Birt Acres, American-born English pioneer of cinematography.