English: The Air Pump
Size Ranking: 62nd.
Area: 239 square degrees
Fully Visible: 49°N-90°S
Antlia, is another of the numerous faint Southern star groupings. Antlia, representative of a mechanical air pump, was introduced on a map published in 1756 by the French astronomer, Nicolas de Lacaille to commemorate the invention of the air pump by French physicist Denis Papin.
This obscure constellation is considerably overshadowed by its glorious southern neighbors, Centaurus and Vela. Lacaille, from an observatory at the Cape of Good Hope, was the first person to completely map the southern skies. To fill gaps between existing constellations, he introduced fourteen new ones, most of which are unremarkable, as is Antlia.
The suggested path to Antlia is to imagine a line joining Sirius, αCMa, with Spica, αVir. The mid point of that line lies approximately just outside the northern boundary of Antlia, as depicted by the red cross in the above diagram.
Features of Interest:
αAnt, at magnitude 4.3, is the constellation’s brightest star. It is an orange giant 366ly distant.
δAnt, is a blue-white star, 481ly away and of magnitude 5.6. It has a magnitude 9.6 companion, separation 11.0”, PA 226°, which should be visible in moderate telescopes.
ζ¹,ζ²Ant, 373ly away, is a wide pair of stars, magnitudes 5.8 and 5.9 respectively, separation 9’51”,visible in binoculars. When a telescope is trained on the brighter of the pair, ζ¹, a pattern of stars, as illustrated below, will be capable of observation. ζ¹ has two component parts, HD82383 and HD82384, separation 11.3”. Each of these parts, in turn, have their own companion viz: HD82383 and SAO200444, separation 4.7”; HD82384 and SAO200445, separation, a mere 0.8”, a dimension that will test the best telescopes!
1. Redshift 2 – Maris Multimedia
2. The Guinness Book of Astronomy – Patrick Moore
3. Stars and Planets – Ian Ridpath and Wil Tirion
Sky Charts – Cartes du Ciel V 2.75