Ara, Triangulum Australe, and Apus - Downloadable article
A spectacular myriad of deep-sky objects fills this southern trio.
March 3, 2009
|This downloadable article is from an Astronomy magazine 45-article series called "Celestial Portraits." The collection highlights all 88 constellations in the sky and explains how to observe each constellation's deep-sky targets. The articles feature star charts, stunning pictures, and constellation mythology. We've put together 11 digital packages. Each one contains four Celestial Portraits articles for you to purchase and download.|
"Ara, Triangulum Australe, and Apus" is one of four articles included in Celestial Portraits Package 6.
The clear skies and warm air of summer offer observers in southern latitudes the opportunity to capture many astronomical gems with their scopes, binoculars, and even the naked eye. This month's tour of the nighttime sky includes three constellations brimming with prime observing objects. These three figures are close enough to the Milky Way's plane to contain a variety of clusters and nebulae, along with a few scattered galaxies.
The northernmost of these constellations, Ara, the Altar, is awash with clusters, lying less than 30° from the Galactic center. A small quadrilateral of 3rd- and 4th-magnitude stars becomes immediately apparent south of the Stinger of Scorpius. Of these four stars, Beta (β), Zeta (ζ), and Epsilon (ε) Arae appear distinctly orange, while Alpha (α) Arae shines an icy blue. In terms of distance, though, Zeta Arae is the odd one, at least twice as far away as the other three, at more than 800 light-years. The luminosities of these four stars vary widely, ranging from Epsilon Arae, 120 times as bright as the sun, to Zeta Arae, which is as bright as 3,000 suns. To read the complete article, purchase and download Celestial Portraits Package 6.
|Deep-sky objects in Ara, Triangulum Australe, and Apus|
IC 4499, NGC 5844, U Apodis, NGC 5938, NGC 6025, R Arae, NGC 6188, Dunlop 206, NGC 6208, NGC 6221, NGC 6250, IC 4633, NGC 6300, IC 4651, NGC 6352, NGC 6362, NGC 6397
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