From the August 2020 issue

Mine Aquila’s deep-sky gems

Star clusters and planetary nebulae will keep you looking at the Eagle all night long.
By | Published: August 19, 2020 | Last updated on May 18, 2023

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Adam Block/NOAO/AURA/NSF
In summer, one of the easiest star patterns to find is the Summer Triangle. The constellation Aquila (pronounced ACK-will-uh) the Eagle is one of the three groups whose Alpha stars — in this case, Altair — make up that popular group. This easy-to-recognize constellation is visible from late spring through late autumn in the Northern Hemisphere. Its center lies at right ascension 19h37m and declination 3°30′.

Although the Eagle’s wingspan might not take up as much space as larger constellations like Hydra (1,303 square degrees), the 22nd-largest constellation still covers a respectable 652.47 square degrees, or about 1.58 percent of the night sky. Its size undercuts its visibility, however; it lies in the middle of the constellation ladder (41st) in terms of overall brightness.

The best date each year to see Aquila is July 14, when it stands opposite the Sun in the sky and reaches its highest point at local midnight. With respect to visibility, anyone living between latitudes 78° north and 71° south can see the entire figure at some time during the year. In fact, portions of it are visible worldwide.

Aquila contains no Messier objects or emission nebulae. Still, as you can see, there are plenty of targets within its borders for you to explore with your telescope. Good luck!

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