1923 in science

Hafnium is a chemical element; it has symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1922, by Dirk Coster and George de Hevesy. Hafnium is named after , the Latin name for Copenhagen, where it was discovered. The element is obtained only by separation from zirconium, with most of the world's hafnium production coming from processes that also produce zirconium. These processes make use

calendar proposed by M. Milanković in 1923 and adopted by some Eastern Orthodox churches

botanical garden in Gothenburg, Sweden

overview of natural science-related events during the year of 1923

20th-century total solar eclipse

20th-century annular solar eclipse

seismometer developed by Harry Oscar Wood & John August Anderson

sociological theory