How to find Sagittarius constellation

Sagittarius Constellation

Fig. 1.Sgr . Sagittarius constellation, diagram

The constellation Sagittarius in mid-latitudes does not rise high above the horizon, while only the northern part of the constellation is visible, the "Arrow" of Sagittarius can only be seen in the southern part of the sky ( declination from -45.5° to -12.03°) .
The best time to study and search for the constellation Sagittarius is from July to September, when the constellation is available for observation in the evening (right ascension from 17^h 36^m to 20^h 20^m).

1. The most universal way to determine the location of the Sagittarius constellation is to approach the constellation from the Polar Star through Alpha Lyra - Vega (Fig. 6.Sgr):

Рис. 6.Sgr. How to find the constellation Sagittarius, based on the North Star

(When copying a figure, please keep its numbering from the original article fig. 6.Sgr - "Constellation Sagittarius", a link to the original is required.)

If you draw a line from the North Star to Lyra and continue it the same length further, then it will lead to the asterism Sagittarius Arrow. If the continuation of the line goes beyond the horizon in the southeast, then the Arrow will soon rise. If the line leads beyond the horizon in the western part of the sky, then in order to see the constellation Sagittarius, you need to start observing early the next day ...

2. The second way to determine the location of Sagittarius in the sky is to "aiming" at the stars of the constellation from the side of the "Summer Triangle" (the "Summer Triangle" asterism is a triangle with vertices from the stars Vega [Alpha Lyrae], Altair [Alpha Aquilae], Deneb [Alpha Cygnus]). The shortest and most accurate sight is obtained from the star Jenach (Epsilon Cygnus) through Altair to Nunki - Sigma Sagittarii (Fig. 7.Sgr). It is also worth remembering that the beam drawn from Deneb through Altair will pass next to Alpha Sagittarius Rukbat.

Fig. 7.Sgr. How to find the constellation Sagittarius by the stars of the Summer Triangle, from the constellation Cygnus you get an accurate sight on Nunki (σ Sgr)

3. The Moon, during its monthly round of the zodiacal circle, can undoubtedly help find the constellation Sagittarius, since it directly passes through it. Only, in order to avoid the illumination of the stars, it is better to look for and consider the constellation, either before the Moon enters it, or after it passes through it. About the nearest approach time of the night luminary to the constellation Sagittarius can be found on the page: Moon - a guide to the constellations

4. Now it remains only to correctly determine the angular dimensions of the constellation Sagittarius.
In mid-latitudes, the constellation Sagittarius, even at its culmination, is not completely shown above the horizon. In Moscow, for example, the maximum angular elevation of Kaus Australis above the horizon is only 0.3° (taking into account the refraction of the atmosphere, it can reach 0.8°) . Kaus Australis will be best seen above the horizon in early July, and exactly at midnight from June 6 to 7 it can be found by compass - at this moment the red arrow will point exactly to Epsilon Sagittarius.
Figure 8.Sgr shows a view of the southern part of the starry sky in Moscow at the time of the maximum rise of the constellation Sagittarius:

Constellation Sagittarius view at the latitude of Moscow. Chart author Sergey OvConstellation Sagittarius view at the latitude of Moscow. Chart author Sergey Ov Sergey Ov

Fig. 8.Sgr. The constellation Sagittarius is the culmination at the latitude of Moscow

As can be seen from the figure, the asterism Arrow is almost completely placed in the gap between the thumb and forefinger of the outstretched hand, that is, it is approximately 17 - 18 °. The angular distance from the northeastern edge of the Arrow of the star Albaldach  (π Sgr; 2.88^m, white-yellow) to the brightest star Kaus Australis (ε Sgr; 1.79^m, blue-white) is 16.75° (Angular distance between stars - online calculation).

Sergey Ov (Seosnews9): Constellation Sagittarius, Sagittarius (Sgr), the fifth constellation of the zodiac group