Circinus Zirkel

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Lateinischer Name: Deutscher Name: Cir Circinus Zirkel Atlas (2000.0) Karte Cambridge Star Kulmination um 17, 20 Atlas Mitternacht: 21, 25, Sky Atlas Cir_chart.gif 26 Cir_chart.gif 1. Mai Deklinationsbereich: -71° ... -55° Fläche am Himmel: 93° 2 Benachbarte Sternbilder: Aps Cen Lup Mus Nor TrA Geschichte: Dieses unscheinbare Sternbild wurde 1752 von dem französischen Astronomen Lacaille eingeführt. Es stellt einen Zeichenzirkel dar und soll, zusammen mit Norma (Winkelmass), an die Navigationshilfsgeräte der Seefahrer erinnern. [bk7 ] Abbé Nicolas Louis de Lacaille wurde 1713 in Rumigny, Frankreich, geboren. Bis 1739 unterrichtete er Mathematik am Mazarin Kollegium in Paris. 1750 reiste er ans Kap der Guten Hoffnung nach Südafrika und führte 14 neue Sternbilder ein, indem er meist alte und größere auseinander nahm. Weiterhin machte er wichtige Messungen an Mond, Venus und Mars und katalogisierte etwa 10'000 Sterne. Nach seiner Rückkehr nach Paris überarbeitete er seine Daten - ein Prozess bei dem er 1762 von seinem Tode überrascht wurde. Sein Werk Coelum Australe Stelliferum wurde im folgenden Jahr herausgegeben. [dq1 ] Sternbild: Das mit 93 Quadratgrad sehr kleine Sternbild Circinus befindet sich östlich vom Stern Rigil Centaurus . Es gleicht in etwa dem Sternbild Triangulum des nördlichen Himmels, denn es bildet mit seinen drei hellsten Sternen alpha, beta und gamma (3. bis 4. Größe) ein ähnlich schmales, spitzes Dreieck, das einen leicht gespreizten Zirkel darstellen soll. Zumindest befindet es sich in der Milchstrasse und enthält somit noch einige wenige Sternhaufen. Das Sternbild kulminiert jeweils etwa am 1. Mai um Mitternacht. [bk9 , bk15 ] Interessante Objekte: Hellste Sterne: alpha Circini beta Circini gamma Circini Offene Sternhaufen: NGC 5715 NGC 5823 Planetarische Nebel: NGC 5315 Galaxien: ESO 97-G13: Circinus Galaxy zusammengestellt von: GERHARD KERMER NOE VOLKSSTERNWARTE 3074 MICHELBACH NOE AMATEURASTRONOMEN .

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