For backyard astronomers in the northern hemisphere the night sky at this time of year is dominated by the three constellations Cygnus (the Swan), Lyra (the Lyre) and Aquila (the Eagle) which lie close to the overhead point during summer evenings as seen from mid-northern latitudes. Particularly prominent is the triangle formed from the bright stars Deneb in Cygnus, Vega in Lyra and Altair in Aquila. Known as the Summer Triangle, this trio of stars is unmistakable and from here many of the other constellations depicted on the chart can be located.
If you look in the region of sky between, and slightly to the east of, Aquila and Cygnus you will spot the three smaller groups Vulpecula (the Fox), Sagitta (the Arrow) and Delphinus (the Dolphin) while to the immediate southwest of Aquila is the faint but distinctive shape of Scutum (the Shield). All four of these constellations should be visible to the naked eye if the sky is dark and clear, although a pair of binoculars will help you to pick them out.
To the west of Lyra we see the conspicuous quadrilateral of stars marking the constellation of Hercules. Known as the ‘Keystone’, the rest of Hercules can be seen spreading away from it. Look immediately to the west of Hercules and you will spot the distinctive circlet of stars forming Corona Borealis (the Northern Crown), just beyond which is part of the constellation Boötes (the Herdsman). Boötes is described elsewhere on this site and is depicted in full on the Northern Spring / Southern Autumn chart.
If the sky is really dark and clear you should be able to trace the winding pattern of Serpens Caput (the ‘head’ of the Serpent) snaking southwards from a point immediately to the south of Corona Borealis. Following the line of stars shown here will lead you to Ophiuchus (the Serpent Holder) with, to the east of Ophiuchus, the smaller line of stars depicting Serpens Cauda (the ‘tail’ of the Serpent). According to Greek mythology, Ophiuchus represents Asclepius, the god of medicine and son of Apollo. He is shown holding the head of the serpent in his left hand and the tail in his right hand, thereby splitting the constellation Serpens into two parts.
To the southwest of Ophiuchus, and situated a little way above the southern horizon as seen from mid-northern latitudes, is the brilliant red Antares, the leading star in Scorpius (the Scorpion). The name Antares can be loosely translated as ‘rival of Mars’ from the fact that, when Mars (often referred to as the Red Planet) and Antares are seen in the same area of sky, the two objects rival each other for prominence.
Just to the west of Scorpius is the somewhat less distinctive constellation Libra (the Scales) while to its east is the large and sprawling Sagittarius (the Archer). Drawing our attention deeper into southern skies is the distinctive circlet of stars forming Corona Australis (the Southern Crown) which lies immediately to the south of Sagittarius. The faint constellation Microscopium (the Microscope) can be seen nearby as can the two faint groups Indus (the Indian) and Telescopium (the Telescope), both of which occupy the region of sky immediately to the south and both of which lie close to the relatively bright star Peacock in the constellation Pavo (see South Circumpolar Stars).
Microscopium, Indus and Telescopium are all relatively faint and you may need a fairly dark, clear night in order to pick them out. Somewhat easier to locate is the tiny but nonetheless distinctive Ara (the Altar) which can be found just to the south of the prominent curve of stars forming the Sting of Scorpius. The last three constellations depicted here are Norma (the Level), Lupus (the Wolf) and Circinus (the Compasses) which, although not particularly prominent, can be tracked down fairly easily in view of their proximity to the bright pair of stars Alpha and Beta Centauri.