{{Short description|French astronomer and admiral}} {{Infobox scientist | name = Ernest Mouchez | image = Amiral Mouchez.jpeg | birth_date = {{birth date|1821|8|24|df=yes}} | birth_place = [[Madrid]], [[Spain]] | death_date = {{death date and age|1892|6|25|1821|8|24|df=yes}} | death_place = [[Wissous]], [[Seine-et-Oise]] | citizenship = French | fields = [[Astronomy]], [[Cartography]] | workplaces = [[French Navy]], [[Paris Observatory]] | alma_mater = | known_for = [[Carte du Ciel]] }}

'''Ernest Amédée Barthélemy Mouchez''' ({{IPA|fr|ɛʁnɛst amede baʁtelemi muʃe}}; 24 August 1821 – 25 June 1892) was a French [[naval officer]] who became director of the [[Paris Observatory]] and launched the ill-fated ''[[Carte du Ciel]]'' project in 1887.

==Life== Born in [[Madrid]], [[Spain]], Mouchez embarked on a career in the [[French Navy]] as an [[Comparative military ranks|ensign]] in 1843. This was a period of relative international maritime peace and much of the navy's activities were dedicated to exploration and discovery. Mouchez was initially occupied on [[Hydrography|hydrographic]] studies along the coasts of [[Korea]], [[China]] and [[South America]], penetrating 320&nbsp;km up the [[Paraguay River]] and exploring the [[Abrolhos Archipelago|Abrolhos Islands]]. He improved the practice of [[surveying]] at sea, adapting terrestrial instruments for naval use, and was especially concerned with the problems of determining [[longitude]]. He developed the use of the [[theodolite]] and [[meridian telescope]] to improve the error in establishing longitude from around 30″ to 3–4″.<ref name="DSB">Simpkins (1981)</ref>

Attaining the rank of [[List of comparative military ranks|post captain]] in 1868, he embarked on a series of expeditions to chart the coast of [[Algeria]].<ref name="DSB"/> However, in 1870, during the [[Franco-Prussian War]], he was called upon to make an heroic defence of the port of [[Le Havre]].<ref>[Anon.] (1893)</ref>

Returning to his Algerian survey, he brought it to a conclusion in 1873, when he was elected to the [[Bureau des Longitudes]] and, in the following year, was sponsored by the ''[[Académie des sciences]]'' to observe the [[1874 transit of Venus|transit of Venus]] from [[Île Saint-Paul|St. Paul Island]] in the [[Indian Ocean]]. On 9 December he made a sequence of superb photographic plates of the event.<ref name="DSB"/>

In 1875, the ''Académie'' elected him a member of the [[astronomy]] section and in 1878 he was promoted to [[List of comparative military ranks|rear admiral]] and awarded the role of director of the Paris Observatory. The [[observatory]] had fallen into disrepair and disrepute since the chaos of the 1870 war and the [[Paris Commune]] of 1871. Mouchez set about a programme of reconstruction but failed to persuade the government to fund a new observatory outside the centre of [[Paris]].<ref name="DSB"/>

In 1887, he collaborated with [[David Gill (astronomer)|Sir David Gill]] to host an international astronomical conference in Paris. The principal outcome of the conference was a multi-national project to compile and index a photographic atlas of the heavens, the ''Carte du Ciel''. The project consumed massive effort over several decades before it was rendered obsolete by modern astronomical methods.<ref name="DSB"/><ref>[Anon.] (2001)</ref>

Mouchez died in [[Wissous]], [[Seine-et-Oise]].<ref name="DSB"/>

{{Gallery |title=Nautical charts and maps from surveys by Mouchez |width=250 |File:Abrolhos Archipelago cropped from Admiralty Chart No 3157 Itacolomis Reef to Rio Doce, Published 1900.jpg |Abrolhos Archipelago, Brazil |Admiralty Chart No 2555 Port of Algiers, Published 1877.jpg |Port of Algiers |Ile St Paul archivesdezoolog6187laca 0737, Surveyed 1874, Published 1877.jpg |Ile St Paul }}

==Honours== *A statue in [[Le Havre]] was unveiled by [[Benjamin Baillaud]] in 1921.<ref name="DSB"/> *A Street in Paris was given his name.

==References== {{reflist}}

==Works== *''Recherches sur la longitude de la côte orientale de l'Amérique du sud'' (1866) * ''Rio de la Plata. Description et instructions nautiques'' (1873) *''Instructions nautiques sur les côtes d'Algérie'' (1879) *''Rapport annuel de l'Observatoire de Paris'' (1885–1892) *''La photographie astronomique à l'Observatoire de Paris et de la Carte de ciel'' (1887) *''Instructions nautiques sur les côtes du Brésil'' (1890) *[https://bibnum.obspm.fr/ark:/11287/3tC7V Works digitalized] on [[Paris Observatory]] digital library

==Sources== *[Anon.] (1875) ''Notice sur les travaux scientifiques de M. Mouchez'', Paris *[Anon.] (1892) ''Polybiblion'', 2nd ser. '''36''', July–December *{{ cite journal | title=Obituary: List of Fellows and Associates deceased during the year: Amédée Ernest Barthélemy Mouchez | journal=[[Monthly Notices of the Royal Astronomical Society]] | volume=53 | pages=226–229 | date=1893 | bibcode=1893MNRAS..53..226. | author=[Anon.] | doi=10.1093/mnras/53.4.226|url=https://archive.org/details/paper-doi-10_1093_mnras_53_4_226| doi-access=free }} *[Anon.] (2001) "Carte du ciel", ''[[Encyclopædia Britannica]]'', Deluxe CDROM edition *{{ cite journal | title=The fading star of the Paris Observatory in the nineteenth century: astronomers' urban culture of circulation and observation | author=Aubin, D. | journal=Osiris | volume=18 | date=2003 | issue=1 | pages=79–100 | doi=10.1086/649378 | bibcode=2003Osir...18...79A | s2cid=143773138 }} *Simpkins, D. M. (1981) "Mouchez, Ernest Barthélémy", in {{cite book | editor=Gillespie, C. C. | date=1981 | location=New York | title=Dictionary of Scientific Biography | publisher=[[Charles Scribner's Sons]] | isbn=0-684-16970-3 }} *Vapereau, G. (ed.) (1880) ''Dictionnaire universel des contemporains'', 5th ed., Paris

===Catalogues of Mouchez' works=== *Royal Society, ''Catalogue of Scientific Papers'', IV 498, VIII 488, X 864; *Poggendorff, III 940, IV 1034-1035; *''Catalogue général des livres imprimés de la Bibliothèque nationale'', CXX, cols.533–538.

==External links== {{Commons Category|Ernest Mouchez}} * {{Cite EB1911|wstitle= Mouchez, Amédée Ernest Barthélémy | volume= 18 |last1= Clerke |first1= Agnes Mary |author1-link= Agnes Mary Clerke | pages = 931&ndash;932 |short=1}} *{{cite web | title=Mouchez, Ernest Amédée Barthélemy (1821–1892) | work=Imago Mundi | url=http://www.cosmovisions.com/Mouchez.htm | language=French | access-date=27 August 2007 | archive-url= https://web.archive.org/web/20070926212502/http://www.cosmovisions.com/Mouchez.htm| archive-date= 26 September 2007 | url-status= live}}

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{{DEFAULTSORT:Mouchez, Amedee}} [[Category:1821 births]] [[Category:1892 deaths]] [[Category:19th-century French astronomers]] [[Category:French Navy admirals]] [[Category:Members of the French Academy of Sciences]] [[Category:French scientific instrument makers]] [[Category:Scientists from Madrid]] [[Category:Recipients of the Lalande Prize]]