In this article, we’ll be sharing with you everything you need to know about the constellation of Sagitta, including how to find it, deep space objects contained within it and how to use it to find other night sky objects more easily.

The Constellation of Sagitta 

Sagitta is one of the constellations that Greek astronomer Ptolemy cataloged over ,2000 years ago. The most common Greek myth about this constellation is about Heracles and Prometheus.

Prometheus created men and women in the gods’ likeness and gave them fire that he’d stolen from the gods. Zeus punished Prometheus by chaining him to Mount Caucasus where an eagle gnawed his liver each day.

Prometheus’ liver regrew each night and his ordeal continued the following morning. Heracles found Prometheus, freed him and killed the eagle with an arrow. The eagle is represented by the constellation Aquila and the arrow is represented by the constellation Sagitta. 

In another Greek myth Sagitta, represents the arrow that Apollo used to revenge himself on the Cyclopes. Apollo’s son Asclepius was killed by Zeus’s thunderbolts and the Cyclopes made the thunderbolts. In a third Greek myth, Sagitta is associated with the arrow that made Zeus fall in love with Ganymede. 

To help you spot Sagitta, here’s what SkySafari 6 shows.

Sagitta as shown by SkySafari
Sagitta as shown by SkySafari. Click for full-screen.

Sagitta has an area of 80 square degrees making it the 86th largest of the 88 recognized constellations. In other words, it is the third smallest of them all. Sagitta is an arrow-shaped constellation.

The boundaries and neighboring constellations for Sagitta
The boundaries and neighboring constellations for Sagitta. Click for full-screen.

As you can see in the The constellation of Sagitta is bordered by the constellations Aquila, Delphinus, Hercules and Vulpecula

In the next section discover how to find Sagitta.

How To Find Sagitta In The Night Sky

Sagitta is part of the Hercules family of constellations and is visible to observers at latitudes between +90° and -70°. It’s visible from every location on Earth except the Antarctic Circle. Northern Hemisphere observers can see it from April to December and Southern Hemisphere observers can see it from May.

Sagitta at 10:00 p.m. on the 3rd of September
Sagitta at 10:00 p.m. on the 3rd of September. Click for full-screen.

To find Sagitta, do a naked-eye search for the Summer Triangle. Draw an imaginary line ~33° long from Altair to the midpoint between Vega and Deneb (Vega and Deneb are ~24° apart). Delta Sagittae is along this line and ~10° from Altair within the Summer Triangle. You can measure these distances with your hand at arm’s length.

To find Sagitta’s exact position for your location on any night, use software such as Stellarium (free) or SkySafari.

Sagitta’s Brightest Stars 

As you might expect, Sagitta has very few bright stars because it is such a small constellation. The image below shows the few stars that are brighter than magnitude five, and there is more information on each underneath that.

The brightest stars of Sagitta
The brightest stars of Sagitta. Click for full-screen.

Alpha Sagittae (Sham, Alsham) – This double star is the third brightest star in Sagitta. The magnitude 4.38, yellow, bright giant primary and its magnitude 13.20 secondary component are 28.9 arcseconds apart. Alpha Sagittae is 475 light-years away. Both of its traditional names mean ‘the arrow’ in Arabic.

Beta Sagittae – This magnitude 4.38, orange giant is 440 light-years away. Its mass is 1.1 Solar masses, its diameter is 28.0 Solar diameters, and it’s 17% cooler than the Sun.

Gamma Sagittae – This magnitude 3.50, orange-red giant is the brightest star in Sagitta and is located at the tip of the arrow. Gamma Sagittae is 275 light-years away. 

Delta Sagittae – This variable double star is the second brightest star in Sagitta. The magnitude 3.82, orange bright giant primary and its magnitude 4.94 secondary component are 0.1 arcseconds apart. Delta Sagittae is 594 light-years away.

Zeta Sagittae – This double star is 255 light-years away. The magnitude 5.03 white main-sequence primary and its magnitude 6.04 secondary star are 0.2 arcseconds apart. 

Eta Sagittae – This magnitude 5.09, orange giant is an eruptive variable 106 light-years away from us. Its mass is 1.2 Solar masses, its diameter is 9.6 Solar diameters and it’s 24% cooler than the Sun.

Star Hopping From Sagitta 

Sagitta is too small and too dim to be a good starting point for star hopping.

Objects To See Within Sagitta 

Sagitta contains one Messier object and one other deep sky object suitable for small telescope users. 

M71 (NGC 6838) – This globular cluster has a magnitude of 8.18 and an apparent size of 3.3 arcminutes. It’s 13,000 light-years away and is at right ascension 19h 54m 46s and declination 18° 50’ 11”.

NGC 6839 – This open cluster has an unknown magnitude and an apparent size of 6.0 arcminutes. It’s 4599 light-years away and is at right ascension 19h 55m 32s and declination 17° 59’ 27”.

Summary

Sagitta is the third smallest constellation and, accordingly, has only a handful of bright stars. However, it is home to a Messier object. Look for it within the bottom corner of the Summer Triangle. 

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