ASTRONOMER

Pierre Janssen

1824 - 1907

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Pierre Jules César Janssen (22 February 1824 – 23 December 1907), usually known as Jules Janssen, was a French astronomer who, along with English scientist Joseph Norman Lockyer, is credited with discovering the gaseous nature of the solar chromosphere, but there is no justification for the conclusion that he deserves credit for the co-discovery of the element helium. Read more on Wikipedia

Since 2007, the English Wikipedia page of Pierre Janssen has received more than 201,055 page views. His biography is available in 47 different languages on Wikipedia (up from 43 in 2019). Pierre Janssen is the 53rd most popular astronomer (up from 141st in 2019), the 852nd most popular biography from France (up from 1,876th in 2019) and the 4th most popular French Astronomer.

Pierre Janssen is most famous for discovering the element helium.

Memorability Metrics

  • 200k

    Page Views (PV)

  • 64.10

    Historical Popularity Index (HPI)

  • 47

    Languages Editions (L)

  • 9.89

    Effective Languages (L*)

  • 2.74

    Coefficient of Variation (CV)

Among ASTRONOMERS

Among astronomers, Pierre Janssen ranks 53 out of 644Before him are Ferdinand Verbiest, Vera Rubin, Clyde Tombaugh, Riccardo Giacconi, William Lassell, and Varāhamihira. After him are Heinrich Louis d'Arrest, William Alfred Fowler, Max Wolf, Johann Bayer, Antony Hewish, and Pieter van Musschenbroek.

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Contemporaries

Among people born in 1824, Pierre Janssen ranks 10Before him are Gustav Kirchhoff, William Thomson, 1st Baron Kelvin, Eugène Boudin, Jean-Léon Gérôme, Maria Alexandrovna, and Paul Broca. After him are Pierre Puvis de Chavannes, Wilkie Collins, Marie Duplessis, Carl Reinecke, Dayananda Saraswati, and Antoine, Duke of Montpensier. Among people deceased in 1907, Pierre Janssen ranks 12Before him are Oscar II of Sweden, Henri Moissan, Hector Malot, Joris-Karl Huysmans, Alfred Jarry, and Giosuè Carducci. After him are Robert I, Duke of Parma, Asaph Hall, Joseph Joachim, Jean Casimir-Perier, Mozaffar ad-Din Shah Qajar, and Kato Svanidze.

Others Born in 1824

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Others Deceased in 1907

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In France

Among people born in France, Pierre Janssen ranks 852 out of 6,770Before him are Pierre Lescot (1515), Paul Reynaud (1878), Jacques Anquetil (1934), Dora Maar (1907), Bertrada of Laon (720), and Arnaut Daniel (1150). After him are Bruno Cremer (1929), Alain-René Lesage (1668), Léon Gambetta (1838), Dominique Strauss-Kahn (1949), Emmanuelle Riva (1927), and Georges Picquart (1854).

Among ASTRONOMERS In France

Among astronomers born in France, Pierre Janssen ranks 4Before him are Charles Messier (1730), Nicolas-Louis de Lacaille (1713), and Jérôme Lalande (1732). After him are Pierre Méchain (1744), Jacques Cassini (1677), Nicolas-Claude Fabri de Peiresc (1580), Jean Picard (1620), Édouard Stephan (1837), Alphonse Borrelly (1842), Auguste Charlois (1864), and Joseph-Nicolas Delisle (1688).