Rømer, Ole

▪ Danish astronomer
Rømer also spelled  Römer, or Roemer, Ole  also spelled  Olaus or Olaf 
born Sept. 25, 1644, Århus, Jutland
died Sept. 23, 1710, Copenhagen
 astronomer who demonstrated conclusively that light travels at a finite speed.

      Rømer went to Paris in 1672, where he spent nine years working at the Royal Observatory. While there he noticed that the time elapsed between eclipses of Jupiter's moons by Jupiter became shorter as Earth moved closer to Jupiter and became longer as Earth and Jupiter drew farther apart. He correctly deduced that this phenomenon was caused by the time needed for light to cross the increased distance between the two planets and in 1676 announced that, according to his observations, the speed of light was 140,000 miles (225,000 km) per second. (Modern measurements have established a figure of 186,282 miles, or 299,792 km, per second.)

      In 1679 Rømer went on a scientific mission to England, where he met Sir Isaac Newton and the astronomers John Flamsteed and Edmond Halley. Upon his return to Denmark in 1681, he was appointed royal mathematician and professor of astronomy at the University of Copenhagen. At the university observatory he set up an instrument with altitude and azimuth circles and a telescope, which accurately measured the position of celestial objects. He also held several public offices, including that of mayor of Copenhagen in 1705.

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Universalium. 2010.

Look at other dictionaries:

  • Rømer, Ole — ► (1644 1710) Astrónomo danés. Determinó la velocidad de la luz a partir de las medidas realizadas en los eclipses de los satélites de Júpiter …   Enciclopedia Universal

  • Römer , Ole Christensen — (1644–1710) Danish astronomer Born at Aarhus, Denmark, Ole (or Olaus) Römer was professor of astronomy at the University of Copenhagen when Jean Picard visited Denmark to inspect Tycho Brahe s observatory at Uraniborg. Picard recruited him and… …   Scientists

  • Rømer — Rømer, Ole …   Enciclopedia Universal

  • Ole Rømer — Rømer redirects here. For other uses, see Romer (disambiguation). Ole Rømer Ole Rømer, portrait by Jacob Coning from c. 1700 …   Wikipedia

  • Ole Roemer — Ole Rømer Olaf Christensen Römer (* 25. Septemberjul./ 5. Oktober 1644greg. in Aarhus; † 19. September 1710 in Kopenhagen)[1], auch Ole oder Olaus mit Vor , sowie R …   Deutsch Wikipedia

  • Ole Römer — Ole Rømer Olaf Christensen Römer (* 25. Septemberjul./ 5. Oktober 1644greg. in Aarhus; † 19. September 1710 in Kopenhagen)[1], auch Ole oder Olaus mit Vor , sowie R …   Deutsch Wikipedia

  • Ole Christensen Romer — Ole Christensen Rømer Pour les articles homonymes, voir Römer (homonymie). Ole Christensen Rømer Naissance …   Wikipédia en Français

  • Ole Rømer — Ole Christensen Rømer Pour les articles homonymes, voir Römer (homonymie). Ole Christensen Rømer Naissance …   Wikipédia en Français

  • Ole Rømer — Ole Christensen Rømer Nacimiento 25 de sep …   Wikipedia Español

  • Ole Christensen Roemer — Ole Christensen Rømer Pour les articles homonymes, voir Römer (homonymie). Ole Christensen Rømer Naissance …   Wikipédia en Français

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