Aaronson, Marc (1950 - 1987) r
Abalakin, Viktor Kuz'mich (1930 - ) r
Abbe, Ernst Carl (1840 - 1905) r
Abbo [Albo] ( - 1004) r
Abbot, Charles Greely (1872 - 1973) r
Abbott, Francis () r
Abel, Niels H. (1802 - 1829) r
Abell, George Ogden (1927 - 1983) r
Abetti, Antonio (1846 - 1928) r
Abetti, Giorgio (1882 - 1982) r
Abney, William de Wiveleslie (1843 - 1920) r
Abraham Ben Chaja (12. Century) r
Abraham Ben Dior (12. Century) r
Abraham Ben Esra [Aben Esra ] (12. Century) r
Abraham Zachut (15. Century) r
Abu Dschaasar Almansur (712 - 775) r
Abu'l Fida [Abulfeda], Ismail (1273 - 1331) r
Achmed Ibn Ketir [Alfraganus] (10. Century) r
Achmed Ibn Mohammed Alsagan Abu Hamed ( - 980) r
Acosta, Cristobal (1515 - 1580) r
Acronius, Johannes (1520 - 1564) r
Adams, Charles Edward (1870 - 1945) r
Adams, Charles H. (1868 - 1951) r
Adams, George ( - 1786) r
Adams, George (1750 - 1795) r
Adams, John Couch (1819 - 1892)v
Adams, Walter Sydney (1876 - 1956) r
Adams, William Grylls (1836 - 1915) r
Adelbulner, Michael (1702 - 1779) r
Agardh, John Mortimer (1812 - 1862) r
Agassiz, George Russell (1862 - 1951)
Agatharchides (2. Century B.C)
Agelet, Joseph le Comte de' [Lepante, Lepaute] (1751 - 1788)
Agrippa (ca. 90)
Aguilar y Vela, Antonio (1820 - 1882)
Aguilar, Eng. Felix ( - 1943)
A'Hearn, Michael F. ()
Ahnert, Eva (1912 - 1954) r
Ahnert, Paul (1897 - 1989) r
Aho, Arne J. ()
Ailli, Pierre d' (1350 - 1425)
Ainslie, M. A. ()
Airy, George Biddell (1801 - 1892) r
Aitken, Robert Grant (1864 - 1951) r
al-Bakri, A. A. (1040 - 1094)
al-Batani [Albategnius], Muhammed ben Geber (852 - 929)
Alberts, B.
Albirunius [al-Biruni] ( - 1029)
Albohazen [Albuassin] (13. Century)
Albrecht, Carl Theodor (1843 - 1915) r
Albrecht, Sebastian (1876 - ) r
Albumassarem (9. Century)
Alcock, George Eric Deacon (1912 - )
Alden, Harold Lee (1890 - 1963) r
Aldrin jr., Edwin E. (1930 - )
Alembert, Jean le Rond de (1717 - 1783)
Alexander (356 - 323 B.C.)
Alfons X. [Alphonsus] (1221 - 1284)
Alfragan [Alfergan], (ca. 850)
Alfvén, Hannes Olof Gösta (1908 - 1995)
Alhazen, Abu Ali (987 - 1038)
Aliacensis, Pierre d'Ailly (1350 - 1420)
Ali-Kuschdschi [Ali Kushgius] ( - 1474)
Almanon [Al Mamum, Abdalla] (786 - 833)
Almansor [Almeon] (12. Century)
al-Marrakushi [Marokeschi] (ca. 1262)
Alpetragius (12. Century)
Al-Sufi (903 - 986)
Alter, Dinsmore (1888 - 1968) r
Ambartsumian [Ambarcumjan], Viktor Amazaspovich (1908 - 1996) r
Ambronn, Leopold Friedrich Anton (1854 - 1930) r
Ameghino, Florentino (1854 - 1911)
Amici, Giovanni Battista (1786 - 1868) r
Ammonius [Ammonios] (ca. 517)
Amontons, Guillaume (1663 - 1705)
Amundsen, Roald (1872 - 1928)
Anaxagoras (ca. 610 - 428 B.C.)
Anaximander (610 - 546 B.C.)
Anaximenes (585 - 528 B.C.)
Andél, Karel (1884 - 1947)
Andersen, R. ()
Anderson, John August (1876 - 1959)
Anderson, Th. D. ()
Anderson, Wilhelm Robert Karl (1880 - 1940)
Andersson, L. (1943 - 1979)
Anding, Ernst Emil Ferdinand (1860 - 1945)
Andoyer, Marie Henri (1862 - 1929)
Angelitti, Filippo (1856 - 1931)
Angelus [Angeli], Johann (1463 - 1512)
Anger, Carl Theodor (1803 - 1858)
Ångström, Anders Jonas (1814 - 1874)
Anianus (ca. 1450)
Anselmo, Giorgio ( - 1440)
Ansgarius [St. Ansgar] (801 - 864)
Anton, Ferdinand (1842 - 1900)
Antoniadi, Eugène Michael (1870 - 1944)
Antoniazzi, A. (1872 - 1925)
Anuchin [Anutschin, D.N.] (1843 - 1923)
Anville, Jean-Baptiste d' (1697 - 1782)
Apianus [Bienewitz], Peter (1495 - 1552)
Apianus [Bienewitz], Philipp (1531 - 1589)
Apollonius [Apollonios] (3. Century B.C.)
Apono, Peter von [Pietro di Abano] (1250 - 1316)
Arago, Dominique Françoise Jean (1786 - 1853)
Araki, Chikara (1946 - )
Araki, Genichi (1954 - )
Araki, Toshima (1897 - 1978)
Aratus [Aratos] (ca. 315 - 245 B.C.)
Archenhold, Friedrich Simon (1861 - 1939)
Archimedes (ca. 287 - 212 B.C.)
Archytas of Tarent (4. Century B.C.)
Arend, Sylvain (1902 - 1992)
Argelander, Friedrich Wilhelm August (1799 - 1875)
Argyrius [Argyrus], Isaak (14. Century)
Ariadaeus, Philippus ( - 317 B.C.)
Aristarchus of Samos (310 - 230 B.C.)
Aristillus [Aristyll] (ca. 280 B.C.)
Aristoteles (384 - 322 B.C.)
Armellini, Giuseppe (1887 - 1958)
Armstrong, Neil A. (1930 - )
Arnold, Christoph (1650 - 1695)
Arnold, John (1744 - 1799)
Arp, Halton Christian (1927 - )
Arrhenius, S. A. (1859 - 1927)
Artemis
Artsimovich, Lew A. (1909 - 1973)
Aryabhata (476 - 550)
Arzachel [Alzarachel], Abraham (ca. 1080)
Asada, Goryu (1734 - 1799)
Asclepi, Giuseppe (1706 - 1776)
Astapovich, Igor' Stanislavovich (1908 - 1976)
Asten, Friedrich Emil von (1843 - 1878)
Aston, Francis William (1877 - 1945)
Åstrand, Johan Julius (1819 - )
Atkinson, Robert d'Escourt (1898 - 1982)
Atlas
Atwood, G. (1745 - 1807)
Aubert, Alexander (1730 - 1805)
Ausan, A. ()
Autolycos [Autolycus] (ca. 330 B.C.)
Auwers, J. G. F. Arthur von (1838 - 1915)
Auzout, Adrien (1622 - 1691)
Averrhoes (Ibn Rosched, Aben Ruis) (1149 - 1217)
Avery, Oswald T. (1877 - 1955)
Avicenna [Abu Ali Ibn Sina] (ca. 980 - 1037)
Azophi [El-Zuphi, Ibn Zophi, Abulhussein Esophi] [10. Century)
d'Arrest, Heinrich Louis (1822 - 1875) r
d'Azambuja, Henri Lucien (1884 - )

Agassiz, George Russell (1862 - 1951)
Minor Planet (2267) Agassiz is named in his honor.

Agelet, Joseph le Comte de' [Lepante, Lepaute] (1751 - 1788)
J. L. d'Agelet was born on the 25. November 1751 in Thone-la-Long. He studied astronomy as a pupil of Lalande and participated as astronomer on the expedition of Kerguelen in 1773. 1778 he started, on a suggestion by his teacher, to make a new star catalog and used a quadrant made by Bird3. In 1780 de' Agelet presented his voyage diaries to the Academy in Paris, it contained 1600 observations of planets and much more on stars. He died during another expedition with Lapérouse in 1788, which had left France in 1785.

Agrippa (ca. 90)
Agrippa observed and described the occultation of the Plejades by the Moon in the year 92, cited by Ptolemaios in his 'Constructio magna'. A Moon crater is named to honor him.

Aguilar yVela, Antonio (1820 - 1882)
A. Aguilar was founder and director of the Madrid observatory. Beside geodetic observations he published his reports on the solar eclipse of 1867 and 1870 and the transit of Mercury in 1868. He published the 'Annuario del Real Observatorio de Madrid'. In a report on the meteoric shower of November 1868 he mentioned fireballs that illuminated the surroundings of the observatory like the full Moon.

Aguilar, Eng. Felix ( - 1943)
F. Aguilar was director of the La Plata Observatory in Argentinia and founder of the University school of Astronomy and Geophysics. Minor Planet (1800) Aguilar is named in his honor.

A'Hearn, Michael F. ()
Minor Planet (3192) A'Hearn is named in his honor.

Aho, Arne J. ()
Minor Planet (2395) Aho is named in his honor.

Ailli, Pierre d' (1350 - 1425)
Ailli was born in Compiègne in 1350. As a theologian and astronomer he published a work on the Moon cycle and on the necessity of a calendar reformation. He died on the 8. August 1420 or 14254 in Avignon.

Ainslie, M. A. ()

al- Batani [Albategnius], Muhammed ben Geber (852 - 929)
Muhammed ben Geber al-Batani was born in 852 in Batan, Mesopotamia. He observed the sky from Aracta and Racha in Mesopotamia and from Damascus in Syria. He described his observations 882 and 901 in two papers titled 'Zydge Saby' (sabaeic tables). This work was translated by Plato Tiburtinus to Latin, extended and published by Regiomontan in 1573. A new edited version was published in Bologna 1645. Al-Batani discovered the movement of the solar apogee? A Moon mountain-walled plain is named to honor him (Albategnius).

Alberts, B.
Assistant at the Planetary Institute in Frankfurt/Main, Germany.

Albirunius ( - 1029)
Abu-Rihan Mohamed Ibn Hamil Al-Baruni was an astronomer, who traveled to India for years. His papers include one on the theory of the fixed stars (Theoria stellarum fixarum). He died in 1029, one source gives 941.

Rukl?

Albohazen [Albuassin] (13. Century)
Albohazen's work on the positions and movements of the stars was translated by rabbi Juda from Arabic to Spanish. This translated work was dedicated to King Alfons X., who used this work to make alterations to the tables published in 1252. The improved tables were published in 1256.

Albumassarem (9. Century)
He lived around 844 and wrote a paper on the periods of conjuctions. In 844 he observed a comet that appeared close to planet Venus.

Alcock, George Eric Deacon (1912 - )
G. E. D. Alcock is an English amateur astronomer who discovered, together with the Infrared Astronomical Satellite IRAS and the Japanese amateur G. Araki the comet C/1983 H1, IRAS-Araki-Alcock.

Alembert, Jean le Rond de (1717 - 1783)
de Alembert was born in Paris on the 16. November 1717 as 'a child of love' of Madame Tencin and Monsieur Destouches. He studied law and worked as a lawyer, changed to medicine for a better income, but finally decided to work as a mathematician and scientist.

In 1741 the Academy in Paris elected him as member and his works on applied mathematics made him known in the scientific community of Europe. After ten years of mathematics he changed for philosophy and literature. Together with Diderot he published the 'Encyclopédie ou Dictionnaire Raisonné des Sciences des Arts et des Métiers' in the years 1751-80. This work has 17 volumes plus several volumes of tables and supplements. It was reprinted in 1967 by F. Frommann Verlag.

As a mathematician he published two works on astronomy: 'Recherches sur la précession des équinoxes et sur la nutation de l'axe de la terre' (Paris, 1749) and 'Recherches sur différens points importants du système du monde' (Paris, 1754). Jean le Rond de Alembert died in Paris on the 29. October 1783.

Alfons X. [Alphonsus] (1221 - 1284)
Alfons was born on the 23. November 1221 in Toledo and was King of Castille and León between 1252 and 1282. He supported Astronomers of his time and ordered astronomical tables to be prepared between 1248 - 52 in Toledo. These tables are called the Alfonsinic tables. He died in Sevilla on the 4. April 1284. A mountain-walled plain on the Moon is named to honor him as well as a rill (valley) system in this plain. Minor Planet (925) Alphonsina is named in his honor.

Alfragan [Alfergan], Alfragan [Alfergan] [Alfraganus], Achmed Ibn Ketir, al-Farghani [al Fargani], Muhammed Ebn Ketir (? - ca. 840)
see Achmed Ibn Ketir
 

Alfvén, Hannes Olof Gösta (1908 - 1995)
Alfvén is honored by minor planet (1778) Alfvén.

Alhazen, Abu Ali ( - 1038)
Alhazen was born in Bassora. He wrote a work on refraction and the effects of dawn. Another work was on optics in seven volumes. He died in Cairo in 1038.

Ali-Kuschdschi [Ali Kushgius] ( - 1474)
Astronomer and Mathematician in Samarcand and Constantinopel. He was, like his father Salaheddin, one of the Astronomers of Ulugh Beigh in Samarcand.

Almansor [Almeon] (12. Century)
Almansor lived in Toledo, Spain, in the middle of the 12. century. He measured the inclination of the ecliptic in 1150 to be 23° 33.'5 and published astronomical tables.

al-Marrakushi [Marokeschi] (ca. 1262)
al-Marrakushi was mathematician and astronomer in Morocco. Some authors write, that he was Professor in 1222, others give only 1252 to 1257 as the year of his birth6.

Alpetragius (12. Century)
Alpetragius wrote about the motion of the planets among the stars and tried to explain these through the invention of spiral motions.

Al-Sufi (903 - 986)
Abd al-Rhaman Al-Sophi was born on the 7. December 903 (Hegira 291, Moharrem 14) and died 25. May 986 (Hegira 376, Moharrem 13). He wrote astronomic tables and a star catalogue which was based on Ptolemy's Almagest and included own observations. It contains the first record of the Andromeda Galaxy7.

Anaxagoras (ca. 610 - 428 B.C.)
Anaxagoras explained lunar and solar eclipses as natural phenomena. At that time this was considered blasphemy, he had to leave Athens in fear of his life. He died in Lampsakus in 428 B.C.

Anaximander (610 - 546 B.C.)
Anaximander was born in Milet in 610 B.C. He made observations and calculated, based on the solstices and equinoxes, the inclination of the ecliptic. He probably drew a map of his country and made a celestial globe.

Anaximenes (585 - 528 B.C.)

Andél, Karel (1884 - 1947)

Andersen, R. ()
Assistant at the observatory at Copenhagen.

Anderson, John August (1876 - 1959)
John August Anderson was born on the 7. August 1876 in Rollag, Minnesota. Between 1908 and 1916 he was Professor of astronomy at the Johns-Hopkins University in Baltimore and worked from 1916 on at the Mt. Wilson observatory. He died in Altadena on the 2. December 1959.

Anderson, Th. D. ()
Edinburgh. Reported on variable stars in AN 152 (1900).

Anderson, Wilhelm Robert Karl (1880 - 1940)
Wilhelm R. K. Anderson was born on the 28.10.1880 in Minsk. He was a teacher between 1910 an 1920 in Samara and Minsk. Later he lived in Tartu (Dorpat), Estonia, and was lecturer at the University there between 1936 and 1940. Wilhelm Anderson was resettled to Germany in 1940 and died the same year in Meseritz, Pomerania, on the 26. March.

Andersson, L. (1943 - 1979)

Anding, Ernst Emil Ferdinand (1860 - 1945)
E. E. F. Anding was born in Seeberg at Gotha on the 11. August 1860. He was director at the observatory there from 1906 until 1934, when the place was closed. Anding died in Hörselgau near Gotha on the 30. June 1945.

Andoyer, Marie Henri (1862 - 1929)
Marie Henri Andoyer11 was born on the 1. October 1862 in Paris, France. He died in Paris on the 12. June 1929.

Angelitti, Filippo (1856 - 1931)
Filippo Angelitti was born on the 1. May 1856. He received his Dr. math. from the Univ. in Napoli and was from that year on calculator at the observatory at Capodimonte and later director of the observatory at Palermo, Sicily. He died at Palermo on the 25. January 1931.

Angelus [Angeli], Johann (1463 - 1512)
Johann Angelus was born on the 2. March 1463 in Aichen, Bavaria. He was Professor of Astronomy in Vienna and died there on the 29. September 1512. He wrote a work titled 'Ephemerides' in 1489 and a paper on the use of an Astrolabium in 1494.

Anger, Carl Theodor (1803 - 1858)
Carl Theodor Anger was born in Danzig on the 31. July 1803 and worked as a teacher (Professor) at the local Gymnasium. He was also assistant at the Königsberg Observatory. He published several papers on different astronomical topics. He died in Danzig on the 25. March 1858.

Ångström, Anders Jonas (1814 - 1874)
Anders Jonas Ångström was born in Medelpad on the 13. August 1814. From 1842 on he worked at the Stockholm observatory and went as observer to Upsala observatory in 1843. Ångström was promoted Professor in 1858. A Moon crater is named to honor him. In 1872 he was awarded the Rumford medal.

A. J. Ångström died in Upsala on the 21. June 1874.

Anianus (ca. 1450)
Astronomer and Poet, wrote an astronomical poem titled 'Computatus manualis', published in Strasbourg in 1488. This poem contains for the first time the terms Sunt Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libraque, Scorpio, Arcitenens, Caper, Amphora and Pisces.

Anselmo, Giorgio ( - 1440)
Wrote a paper on Astronomy, which is in the Vatican library, beside 18 books of mathematical content. He died 1440 in Parma.

Anton, Ferdinand (1842 - 1900)
Ferdinand Anton was born in 1842 or 184312 in Munker, a village close to Aussig on the river Elbe (today Czech Republic). He was assistant at the observatory in Triest from 1884 on and from 1896 on director. He published ephemerides in German and Italian language and died in Triest on the 1. October 1900.

Antoniadi, Eugène Michael (1870 - 1944)
E. M. Antoniadi was born on the 10. March 1870 in Constantinopel (today Istanbul, Turkey). From 1908 on he was trainee at the Observatoire Meudon. He died in Paris, France, on the 10. February 1944. An obituary is in 'L'Astronomie' 58 (1944), p. 58-60 and in Sky & Telescope 5.

Antoniazzi, A. (1872 - 1925)
A. Antoniazzi was born on the 1. April 1872 in Collato di Refrontolo, Trevisio. From 1893 on he was assistant, from 1903 assistant astronomer, from 1909 astronomer and between 1913 (1915?) and 1925 director of the observatory at Padua. He died there on the 30. November 1925.

Apianus [Bienewitz], Peter (1495 - 1552)
Apianus was born on the 16. April 1495 in Leisnig. He was mathematician and astronomer and published trigonometric tables calculated by him. As an appendix he included Girard's latin translation of the 'Geometric Elements', written by the arabic astronomer Geber (11. century). For his own observations Apianus used an instrument shaped like a quadrant, he called it 'Instrumentum primi mobilis'. He pointed out that comet tails are pointing away from the sun at any time.

Peter Apianus died in Ingolstadt on the 21. April 1552. The live of Peter Apianus and his son Philipp was described by S. Günter in Prag, 1882, Ges. Wiss. Abh.

Apianus [Bienewitz], Philipp (1531 - 1589)
Philipp Apianus is the son of Peter and was born in 1531 in Ingolstadt. He drew a geographic map on 24 sheets, constructed sundials and celestial globes. He died 1589 in Tübingen.

Apono, Peter von [Pietro di Abano] (1250 - 1316)
Apono was born in Abano near Padua and worked there as physician, philosopher and astronomer. He wrote a book about the astrolabe and the planisphere.

Arago, Dominique Françoise Jean (1786 - 1853)
Dominique Françoise Jean Arago was born on the 26. February 1786 in Estagel near Perpignan, France. He was director of the Paris Observatory from 1830 on and secretary of the Academy of Sciences. D.F.J. Arago participated in the determination of longitudes between Barcelona and Formentera. He wrote the four volume "Astronomie Populaire" and some biographical work on contemporary scientists. A micrometer constructed by him used a double prism in front of the objective lens. He also invented the polariscope13 (1811) and used it for astronomic observations. He died in Paris on the 2. October 1853. Minor Planet (1005) Arago is named in his honor. Also craters on the Moon and on Mars bear his name.

Araki, Chikara (1946 - )
Minor Planet (4718) Araki is named in his honor. C. Araki is a photographer of astronomical objects.

Araki, Genichi (1954 - )
G. Araki is a Japanese amateur astronomer who discovered, together with the Infrared Astronomical Satellite IRAS and the English amateur G. E. D. Alcock, the comet C/1983 H1, IRAS-Araki-Alcock.

Araki, Toshima (1897 - 1978)
Toshima Araki was born on the 20. March 1897 in Shikamoto-gun, Kumamoto Prefecture, Japan.

He was Professor from 1940 on and resigned in 1945. Between 1954 and 1964 he was Professor of Astronomy at the Ôtani University in Kyoto and served as first president of the Kyoto Sangyo University between 1965 and 1973. He retired in 1975 as Professor emeritus of the Kyoto University.

Beside other honors he received he was Knight Commander of Grace (Jerusalem, 1973). A list of his works, all in Japanese, is in Pogg. VIII, p. 105.

Toshima Araki died on the 10. July 1978 in Sakyo-ku, Kyoto.

Aratus [Aratos] (ca. 315 - 245 B.C.)
Aratus was born in Solis (Pompejopolis), Asia Minor, and lived at the same time as Ptolemaios Philadelphus (ca. 270 B.C.). He was an astronomer and poet and put the work of Eudoxus into verse on a request by the Macedonian King Antigonus Gonatus. This combination of science and poetry was praised by Cicero and translated by him.

Archenhold, Friedrich Simon (1861 - 1939)
Friedrich Simon Archenhold14 was born in Lichtenau, Germany, on the 2nd October 1861. His father was Moses Archenhold and his mother Rosa, née Blumenfeld.

F.S. Archenhold started his studies in Strasbourg, France, but spent more time in Berlin as a pupil of W. Foerster. From 1891 on he worked on the station Grunewald of the Berlin Observatory. For the Berlin exhibition he was involved in the construction of a refractor with 68 cm (27 inch) diameter and 21 meters (69 feet) focal length, based on his ideas. After the exhibition a public observatory was opened in Berlin-Treptow; it is still in operation today under the name 'Archenhold-Sternwarte'. In 1900 Archenhold founded the popular-science magazine 'Weltraum'.

The whole family Archenhold, of Jewish origin, was deported in 1936 under the national socialist regime. Friedrich Simon Archenhold died on the 14. October 1939 in Berlin, his wife Alice 1943 in the concentration camp Theresienstadt. Their son, Guenther Hermann Archenhold, later was head of the Archenhold-Sternwarte.

Archimedes
Archimedes observed the solstices and constructed an instrument that contained the main circles of the celestial sphere and displayed the motion of the sun, the Moon and the planets. Archimedes was killed in 212 B.C, when Syracuse was taken by Marcellus.

Archytas of Tarent (4. Century B.C.)
Archytas made some astronomical observations in Italy in the 4. century B.C. None of his most mathematical work seems to be conserved. Archytas died in 400 B.C. during a ship wreckage.15

Arend, Sylvain (1902 - 1992)
Sylvain Arend was born in Robelmont on the 6. August 1902 and died at Uccle on the 18. February 1992. S. Arend was astronomer at the Uccle Observatory near Brussels, Belgium. He discovered 50 Minor Planets and, together with G. Roland, the bright comet C/1956 R1 Arend-Roland in November 1956. Minor Planet (1502) Arenda is named in his honor

An Obituary is in Ciel et Terre, Vol. 108, No. 4, p. 101-102 (1992)

Argelander, Friedrich Wilhelm August (1799 - 1875)
Friedrich Wilhelm August Argelander was born in Memel, today in Lithuania, on the 22. March 1799. He was assistant at the University of Königsberg, from 1825 director of the Åbo Observatory and from 1832 director of the Helsingfors Observatory. His observations of Aurorae from these years were published in 1866.

In 1837 he went to Bonn as director of the local observatory. He made observations of proper motions using the catalogs of Bradley and Piazzi. In 1843 he published the 'Neue Uranometrie', a star atlas with the naked eye stars. In 1863 a star atlas and catalog followed that contained 324.198 stars on 40 charts for the epoch 1855.0. In this work Argelander was assisted by Prof. Schönfeld and Prof. Krüger.

Argelander died in Bonn in 1875. A Moon crater is named to honor him as well as Minor Planet (1551) Argelander.

Argyrius [Argyrus], Isaak (14. Century)
Argyrius, born around 1312, was a monk and astronomer, he wrote about the Moon cycle and solar and lunar eclipses. Another work was on the reduction of the data of the 'Almagest', converting the dates from Egyptian to Roman years and the positions from the meridian of Alexandria to Constantinopel (Istanbul). He died after the year 1372.

Ariadaeus, Philippus ( - 317 B.C.)
A Moon crater is named to honor him.

Aristarchus of Samos (310 - 230 B.C.)
Aristarch of Samos teached a heliocentric system, the sun and the stars are fixed, the earth moved around the sun. Most of his works are lost or only available as citations.

A Moon crater as well as a rill (valley) system is named to honor Aristarch. Minor Planet (3999) Aristarchus bears his name.

Aristillus [Aristyll] (ca. 280 B.C.)
Aristillus observed the stars and wrote a book titled 'On fixed stars'. This work and the work of Timochares, who observed together with Aristillus, were used by Hipparcos. A Moon crater is named to honor him. A second astronomer with this name is mentioned in Pogg., but nothing more than his name is known.

Aristoteles (384 - 322 B.C.)
Aristoteles was born in 384 B.C. in Stagira, Macedonia. His parents, Nikomachos, a physician, and Phaestis, were of Greek origin. He wrote on astronomy in his book on Physics. He committed suicide with poison in 322 B.C., because he feared a death sentence, accused to be a disbeliever. He was ordered to Athens to hear his sentence but had fled to Chalcis (Andschar, east of Beirut). A Moon crater is named to honor him.

Armellini, Giuseppe (1887 - 1958)
Giuseppe Armellini was born on the 23. October 1887 in Rome, Italy. From 1923 on he was Professor of astronomy in Rome and director of the observatory at Campidoglio. He published his observations in the AN and in the 'Atti R. Acad. Lincei'.

His works were on the nature of the Moon maria, the four big moons of Jupiter, Neptun's moon and the origin of comets. G. Armellini died on the 16. July 1958 in Rome.

Arnold, Christoph (1650 - 1695)
Christoph Arnold was born in Sommerfeld near Leipzig on the 17.12.1650. He was a farmer who was interested in Astronomy. He discovered the great Comet of 1683 eight days before Hevelius and observed the great Comet of 1686. For his observation of the transit of Mercury in front of the sun on the 13.10.1690 he received an amount of money and a tax exemption from the town of Leipzig. He died in Leipzig on the 15.4.1695 or 1697. A Moon crater is named to honor him.

Arnold, John (1744 - 1799)
J. Arnold, born in Bodmin, Cornwall, in 1744, was a mechanic and clock maker in London. He improved the construction of chronometers and produced them in large numbers.

Arp, Halton Christian (1927 - )
H. C. Arp was born in New York City on the 21. March 1927. He studied at Havard University (Bachelor in 1949) and at CalTech (Ph.D. in 1953). Until a post as research associate at Indiana Univ. (1955-57) he worked at the Mt. Wilson and Palomar Observatories. He returned to Mt. Wilson as assistant astronomer and was appointed astronomer in 1969.

After his 'Atlas of peculiar Galaxies' (1966) he tried to prove that certain Quasars and Galaxies not only appear close together, but are companions in some way and physically connected. (... to be continued)

Aryabhata (476 - 550)
A Moon crater is named to honor him.

Arzachel [Alzarachel], Abraham (ca. 1080)
Abraham Arzachel lived around 1080 in Toledo, Spain, as an Astronomer. A part of his work, the 'Tabulae Toledanae', was used for the 'Alfonsinic tables'. He wrote this work when he found out that the planetary tables of Albategnius were inaccurate. Arzachel gave the maximum declination of the sun as 23° 34'.

Asada, Goryu (1734 - 1799)
A Moon crater is named to honor him.

Astapovich, Igor' Stanislavovich (1908 - 1976)
Igor' S. Astapovich was born on the 11. January 1908 in Volcansk u Charkiva. He was Professor at the University of Kiev and a researcher in meteor astronomy. A list of his work is in Pogg. VIII, p. 159.

Igor' S. Astapovich died on the 2. January 1976. An obituary in Russian language is in Komety i Meteory No. 26 (1977), p. 43-48. Minor planet (2408) Astapovich is named in his honor.

Asten, Friedrich Emil von (1843 - 1878)
Friedrich Emil Asten was born on the 26. January 1842 in Cologne. He studied in Bonn between 1862 an 1865 and received his doctorate (Ph.D.) in that year. From 1866 on he lived in Cologne and went to Berlin in 1869 and in 1870 to Pulkowa as a computer at the observatory there. He was promoted assistant astronomer in 1871. A lot of his published works dealt with comet observations but he also made available his results based on Otto Struve's observations of the moons of Uranus.

Asten died in St. Petersburg on the 15. August 1878.

Aston, Francis William (1877 - 1945)
Francis William Aston was born on the 1. September 1877 in Camomile Green, Harborne, near Birmingham, England. He was a chemist and was honored with the Nobel prize in 1922. He died on the 20. November 1945. A Moon crater is named to honor him.

Åstrand, Johan Julius (1819 - 1900)
Johan Julius Åstrand was born on the 22. September 1819 in Gothenburg, Sweden. He was a teacher of mathematics in Bergen and from 1855 on director of the Marine observatory there. In 1873 he was elected member of the Academy in Cherbourg and in 1878 member of the Royal Astronomical Society in London. An list of his work is published in Pogg. Vol. 3 (1898), p. 47, and includes celestial maps, a work on the calculation of the local deviation of a compass and calculating tables.

J. J. Åstrand died in Bergen on the 19. February 1900.

Atkinson, Robert d'Escourt (1898 - 1982)
Robert d'Escourt Atkinson16 was born on the 11. April 1898 in Rhayader, Wales. He worked on the structure of stars and stellar energy, his works were published in the 'Astrophysical Journal'. Robert Atkinson died in Bloomington, Indiana, on the 28. October 1982. Minor planet (1827) Atkinson is named in his honor.

Aubert, Alexander (1730 - 1805)
Alexander Aubert was born on the 11. May 1730. He observed the transit of Venus across the sun's disk on 3. June 1769 and presented a report on his observations (Phil. Trans. 1769). He died in London on the 19. October 1805.

Ausan, A. ()
Observer at the Tashkent observatory in 1915.

Autolycos [Autolycus] (ca. 330 B.C.)
Autolycos was born in Pitane and was a famous mathematician in Greece. His work 'De sphaera mobili' and another work were published in 1572 by C. Dasypodius in Strasbourg. A Moon crater is named to honor him.

Auwers, J. G. F. Arthur von (1838 - 1915)
Georg Friedrich Julius Arthur von Auwers17 was born on the 12. September 1838 in Göttingen. His father was Gottfried Daniel Auwers (1796 - 1847), master of the horses at the University in Göttingen; his mother Emma Christiane Sophie, née Borkenstein (1818 - 1842). He lost his parents while still a child and was sent to Schulpforta, aged about 12, to finish schooling that he had started in his home town. He studied astronomy in Göttingen and Königsberg and got the post of assistant at the observatory in Königsberg in 1859. In 1862 he received his doctorate (Ph.D.) with a work on variations of the proper motion of the star Procyon (Königsberg, 96 pages). On the 1. November 1862 he married Marie Henriette Jacobi (1837 - 1915) and went to Gotha to work with Hansen.

His interest in astronomy dates back to his school time. He published a work on W. Herschel's catalog of nebula and clusters in 1862 that was prepared by him as early as 1854, when he was aged 16. Later, after a suggestion of F. W. Ristenpart, he revised the catalogs of T. Mayer, Pond, Piazzi and the observations of Bradley and published the last part of these papers shortly before his death. This project covered 170 000 star positions observed between 1753 and 1900. For this work his colleagues presented him a portrait of J. Bradley in 1912, the same year he was ennobled. Another work by Auwers discusses the proper motion of the stars Sirius and Procyon.

In 1866 he was promoted astronomer and member of the Academy of Sciences in Berlin. His work there was only interrupted by three scientific expeditions: in 1874 and in 1882 to Luxor, Egypt and to Punta Arenas, respectively, to observe Venus transits across the Sun, obtaining data for an exact determination of the sun's parallax. The results of these two expeditions filled 6 volumes. Another expedition led him to the Cape of Good Hope to observe minor planet Victoria together with Sir David Gill. In 1881 Auwers was president of the Astronomical Society. A list of his works is published in Pogg., Vol. 3 (1898), p. 51, continued in Pogg. Vol. 4 and 5.

Von Auwers died in Berlin-Lichterfelde on the 24. January 1915. He had three sons, one was the chemist Karl Friedrich von Auwers. A Moon crater is named to honor Arthur von Auwers.

Auzout, Adrien (1622 - 1691)
Auzout was born in Rouen in 1622. He improved the construction of the telescope and developed the micrometer. His paper 'Traité du micromètre etc.' was published in the 'Mem. de l'Acad. ancienne de Paris'. Like Gascoigne befor him he used a telescope attached to a quadrant to improve the quality of the instrument.

He died in Rome (Paris) in 1691 (1695)18. A Moon crater is named to honor him.

Averrhoes (Ibn Rosched, Aben Ruis) (1149 - 1217)
Averrhoes was born in Cordova in 1149 and worked as medical doctor, astronomer and philosopher. He may have observed a transit of Mercury in front of the sun. His works were published in Venezia in 1560.

Averrhoes died in Morocco in 1217 (1198, Hegira 595)19.

Azophi [El-Zuphi, Ibn Zophi, Abulhussein Esophi] (10. Century)
Azophi lived in Baghdad and wrote a paper on theoretic astronomy. He calculated astronomical tables and made a catalog of fixed stars, including pictures of the constellations.

d'Azambuja, Henri Lucien (1884 - )
H. Lucien d'Azambuja was born on the 28.1.1884 in Paris, France. He worked as astronomer at the Observatoire de Paris in Meudon, Section de Astropysique. Between 1949 and 1951 he served as president of the Societé Astronomique de France. In 1952 he was member of the Commision de Direction du Service d'Astrophysique. He received many honors and was Officier de la Légion d'Honneur (France) and Commandeur de l'Ordre de Saint-Jaques-de-l'Epée (Portugal).

H. Lucien d'Azambuja died in 1970.