E. M. Antoniadi

Eugène Michel Antoniadi (Greek: Ευγένιος Αντωνιάδης; 1 March 1870 – 10 February 1944) was a Greek-French astronomer.

Eugène Michel Antoniadi
Eugene Antoniadi.jpg
Eugène Michel Antoniadi
Born(1870-03-01)1 March 1870
Died10 February 1944(1944-02-10) (aged 73)
Years active1893–1944
Known forMaps of Mars and Mercury
Notable work
La planète Mars, 1659-1929


Antoniadi was born in Istanbul, but spent most of his adult life in France, after being invited there by Camille Flammarion.[1]

He became a Fellow of the Royal Astronomical Society on 10 February 1899, and in 1890 he became one of the founding members of the British Astronomical Association (BAA). In 1892, he joined the BAA's Mars Section and became that section's Director in 1896.[2]

He became a member of the Société astronomique de France (SAF) in 1891.[3]

Flammarion hired Antoniadi to work as an assistant astronomer in his private observatory in Juvisy-sur-Orge in 1893.[4] Antoniadi worked there for nine years. In 1902, he resigned from both the Juvisy observatory and from SAF.[2]

Antoniadi rejoined SAF in 1909. That same year, Henri Deslandres, Director of the Meudon Observeratory, provided him with access to the Grande Lunette (83-cm Great Refractor) [5]

He became a highly reputed observer of Mars, and at first supported the notion of Martian canals, but after using the 83 centimeter telescope at Meudon Observatory during the 1909 opposition of Mars, he came to the conclusion that canals were an optical illusion. He also observed Venus and Mercury.

Antoniadi's 1934 map of Mercury

He made the first map of Mercury, but his maps were flawed by his incorrect assumption that Mercury had synchronous rotation with the Sun.[1] The first standard nomenclature for Martian albedo features was introduced by the International Astronomical Union (IAU) when they adopted 128 names from the 1929 map of Antoniadi named La Planète Mars.[6]

He is also famed for creating the Antoniadi scale of seeing, which is commonly used by amateur astronomers. He was also a strong chess player. His best result was equal first with Frank Marshall in a tournament in Paris in 1907, a point ahead of Savielly Tartakower.

He died in Paris, aged almost 74.


His full name was Eugène Michel Antoniadi (Greek: Ευγένιος Μιχαήλ Αντωνιάδης, Evgénios Michaíl Antoniádis), however he was also known as Eugenios Antoniadis. His name is also sometimes given as Eugène Michael Antoniadi or even (incorrectly) as Eugène Marie Antoniadi.

Awards and honorsEdit


Antoniadi was a prolific writer of articles and books (the Astrophysics Data System lists nearly 230 that he authored or co-authored).[8] The subjects included astronomy, history, and architecture. He frequently wrote articles for L'Astronomie of the Société astronomique de France, Astronomische Nachrichten, and the Monthly Notices of the Royal Astronomical Society, among others.

Notable works include:

  • Sur une Anomalie de la phase dichotome de la planète Vénus (Paris: Gauthier-Villars, (s. d.)).[9]
  • La planète Mars, 1659-1929 (Paris: Hermann & Cie, 1930).[10]
  • La Planète Mercure et la rotation des satellites. Etude basée sur les résultats obtenus avec la grande lunette de l'observatoire de Meudon (Paris: Gauthier-Villars, 1934).[11]


  1. ^ a b Hockey, Thomas (2009). "Antoniadi, Eugène Michael". The Biographical Encyclopedia of Astronomers. Springer Publishing. pp. 83–85. doi:10.1007/978-1-4419-9917-7_58. ISBN 978-0-387-31022-0.
  2. ^ a b McKim, R. J. “The life and times of E.M. Antoniadi, 1870-1944. Part I: an astronomer in the making.” Journal of the British Astronomical Association 1993, vol. 103, no. 4, pp. 164-170.
  3. ^ Bulletin de la Société Astronomique de France 1896, p. 415.
  4. ^ a b c d "Antoniadi, Eugène Michel - Archives," cote Ms 1138, Bibliothèque de l'Observatoire de Paris - site de Paris (France), Alidade database, consulted 16 March 2018.
  5. ^ McKim, Richard J. “The life and times of E.M. Antoniadi, 1870-1944. Part II: The Meudon years.” Journal of the British Astronomical Association 1993, vol. 103, no. 5, pp. 219-227.
  6. ^ Shirley, James H.; Fairbridge, Rhodes Whitmore (1997). "Nomenclature". Encyclopedia of planetary sciences. Springer. pp. 543–550. ISBN 978-0-412-06951-2.
  7. ^ McKim, R. J. (August 1993). "The life and times of E.M. Antoniadi, 1870-1944. Part I: an astronomer in the making". Journal of the British Astronomical Association. 103 (4): 164−170. Bibcode:1993JBAA..103..164M. See the introduction.
  8. ^ Harvard Astrophysics Data System, retrieved 5 May 2018.
  9. ^ Bibliothèque nationale de France Gallica catalog entry.
  10. ^ Bibliothèque nationale de France Gallica catalog entry.
  11. ^ Bibliothèque nationale de France Gallica catalog entry.

Further readingEdit

External linkEdit