1929 in science

The year 1929 in science and technology included many events, some of which are listed below.

Astronomy and space exploration

Clyde Tombaugh discovers several asteroids: 2839 Annette, 3583 Burdett, 3824 Brendalee, 1929 VS, 1929 VD1.
Edwin Hubble publishes his discovery that the speed at which galaxies recede positively correlates with their distance, which became known as Hubble's law, the basis for understanding that the universe is expanding.
George Gamow proposes hydrogen fusion as the energy source for stars.
Konstantin Tsiolkovsky proposes the construction of staged rockets in his book Космические поезда (Cosmic Trains).

July 5 – The Curtiss-Wright corporation is founded.
August 8 – The German airship Graf Zeppelin begins a round-the-world flight (will end on August 29).
November 29 – US Admiral Richard Byrd becomes the first person to fly over the South Pole.
December 5 – Grumman Aircraft Engineering Corporation is founded.

Professor Gericke of the University of California, Los Angeles demonstrates that plants can be grown soil-free all the way to maturity, the basis of hydroponics.

Rudolf Hell receives a patent for the Hellschreiber, an early fax machine.
First practical coaxial cable patented by Lloyd Espenschied and Herman Affe of AT&T's Bell Telephone Laboratories.

November 18 – 1929 Grand Banks earthquake: Off the south coast of Newfoundland in the Atlantic Ocean, a Richter magnitude 7.2 submarine earthquake centered on Grand Banks, breaks 12 submarine transatlantic telegraph cables and triggers a tsunami that destroys many south coast communities in the Burin Peninsula area.

Alexander Fleming publishes an article about penicillin in the British Journal of Experimental Pathology, for which he received the 1945 Nobel Prize in Physiology or Medicine

Robert J. Van de Graaff develops the Van de Graaff generator.
Oskar Klein discovers the Klein paradox.
Oskar Klein and Y. Nishina derive the Klein-Nishina cross section for high energy photon scattering by electrons.
Sir Nevill Francis Mott derives the Mott cross section for the Coulomb scattering of relativistic electrons.
Paul Adrien Maurice Dirac and Werner Karl Heisenberg develop the quantum theory of ferromagnetism.
Ernest O. Lawrence invents the cyclotron, for which he received the 1939 Nobel Prize in Physics.