1915 in science

The year 1915 involved numerous significant events in science and technology, some of which are listed below.

Astronomy

January – British physicist Sir Joseph Larmor publishes his observations on "The Influence of Local Atmospheric Cooling on Astronomical Refraction".
March 19 – Pluto is photographed for the first time but is not classified as a planet.
Einstein's new theory of general relativity is used to explain Mercury's strange motions that baffled Urbain Le Verrier.
Robert Innes discovers Proxima Centauri, the closest star to Earth after the Sun.

Alice Ball discovers how to make Chaulmoogra tree oil water-soluble, which makes it usable for patients with leprosy in Hawai'i.
Thomas Lyle Williams produces the mascara Maybelline.

May 22 – Lassen Peak, one of the Cascade Volcanoes in Northern California, erupts, sending an ash plume 30,000 feet in the air and devastating the nearby area with pyroclastic flows and lahars. It is the only volcano to erupt in the contiguous United States between 1900 and 1980.
Alfred Wegener publishes his theory of Pangea, which he calls Urkontinent.

The new theropod dinosaur genus and species Spinosaurus aegyptiacus is assigned by German paleontologist Ernst Stromer.

January – Mildred Hoge publishes her discovery of the gene responsible for development of the eye.
A global pandemic of encephalitis lethargica begins.
Trench nephritis is first reported as affecting soldiers of the British Expeditionary Force in Flanders in the British Medical Journal; the name is coined by Nathan Raw.
Walter Bradford Cannon coins the term fight or flight to describe an animal's response to threats.
Thomas Hunt Morgan, demonstrates non-inherited genetic mutation, undermining the conceptual basis of eugenics.
Reginald Punnett's Mimicry in Butterflies is published in Cambridge
Clara H. Hasse publishes a paper identifying the cause of citrus canker which leads to the development of methods for controlling the disease, saving the citrus crops in the southern United States from being wiped out.

August – Ada Hitchins' experimental results indicating that radium is formed by the decay of uranium are published.
November 25 – Albert Einstein presents to the Prussian Academy of Sciences the Einstein field equations of general relativity. He abandons his hole argument for general relativity.
Arnold Sommerfeld develops a modified Bohr atomic model with elliptic orbits to explain relativistic fine structure.

Danish psychologist Edgar Rubin publishes Synsoplevede Figurer introducing the optical illusion which becomes known as the Rubin vase.

January 11 – Lucille Farrier Stickel, American wildlife toxicologist.
February 26 – Wang Daheng, Chinese optical physicist.
February 28 – Peter Medawar, Brazilian-born British biologist, co-recipient of the Nobel Prize in Physiology or Medicine for his work in immunology.
March 15 – Laurent Schwartz, French mathematician.
March 16 – Kunihiko Kodaira, Japanese mathematician.
May 30 – Henry Aaron Hill, American fluorocarbon chemist and first African American president of the American Chemical Society.
June 15
* Thomas Huckle Weller, American virologist and co-recipient of the Nobel Prize in Physiology or Medicine for his work on polio.
* Xu Ruiyun, Chinese mathematician.
June 19 – Katherine Sanford, American cell biologist.
June 24 – Fred Hoyle, English astronomer and science fiction writer.
July 28 – Charles Hard Townes, American physicist and co-recipient of the Nobel Prize in Physics for developing the maser.
October 1 – Jerome Bruner, American developmental and educational psychologist.
October 26 – Lu Jiaxi, Chinese physical chemist.
November 18 – Tang Aoqing, Chinese quantum chemist.
November 30 – Henry Taube, Canadian-born recipient of the Nobel Prize in Chemistry.
December 5 – Ren Xinmin, Chinese rocket scientist.
December 22 – A. E. Wilder-Smith, English-born organic chemist.