Roentgenium was first made on 8 December 1994 at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, by a team led by Sigurd Hofmann. They bombarded a target of bismuth-209 with nickel-64 nuclei and detected three atoms of the new element, atomic number 111, through their sequence of radioactive decays. The finding was confirmed by later experiments in Germany and Japan. The element was named in 2004 after Wilhelm Conrad Roentgen, the German physicist who discovered X-rays in 1895 and received the first Nobel Prize in Physics in 1901. Roentgenium is a synthetic, intensely radioactive element, with the longest-lived isotope lasting for only minutes, and it can only be produced in tiny quantities.
Before and after
- from 9 November 1994 to 3 October 1995O. J. Simpson murder case
- from 29 November 1994 to 24 December 1994Operation Winter '94
- December 1994Operation Spider
- 5 December 1994Budapest Memorandum
- 8 December 1994Discovery of roentgenium
- from 11 December 1994 to 31 August 1996First Chechen War
- from 31 December 1994 to 8 February 1995Battle of Grozny
- 1995Release of Apache HTTP Server
- 1995Founding of European Medicines Agency
More in Science & technology
- 1945Invention of computer
- 1971Email
- 1973Mobile phone
- July 2000Discovery of livermorium
- 15 January 2001Wikipedia
- 20 October 2004Creation of Ubuntu
The era
This moment belongs to the Contemporary world (1945 CE to today), the world since 1945. You can also browse everything in the 20th century.