This summer holds a variety of celestial events — including planetary conjunctions, lunar occultations and meteor showers. However, those have to be observed on specific nights. Here’s a list of the best five summer asterisms to observe on any night.

What is an asterism? An asterism is a popular pattern of stars rather than an area of the sky like the Plough. Unlike constellations, they are “unofficial” and often resemble their name.

What defines a summer asterism? A summer asterism is one that lies near to the zodiacal constellations opposite to the Sun. During the summer months, the Sun passes through the constellations of Gemini, Cancer and Leo. Summer asterisms are thus located near Sagittarius, Capricorn and Aquarius. This allows us to observe them without the Sun being in that area of the celestial sphere.

1. Summer Triangle — Perhaps the most popular summer asterism consisting of the three bright stars: Deneb, Vega and Altair. Observe it now in the Eastern sky near midnight:

^ Image of the Summer Triangle (Credits: Olesya Rtveliashvili)

2. Northern Cross (Cygnus) — This asterism is basically the body of the “swan ” in Cygnus, consisting of 5 stars that form the shape of a cross. It is near multiple nebulas including the North American Nebula and the Veil Nebula as well as many small open clusters.

3. Keystone (Hercules) — The four central stars of the constellation Hercules create a quadrilateral asterism called the Keystone. Near it lies globular clusters M13 and M92.

4. Job’s Coffin (Delphinus) — The head of the “dolphin” in Delphinus is sometimes referred to as Job’s Coffin. Four bright stars create a diamond-like shape, two of which are spectroscopic binaries and one is a Delta Scuti type variable star.

5. Northern Crown (Corona Borealis) — the crown-like pattern of stars in Corona Borealis is sometimes labelled as the asterism of Northern Crown. Alphecca, the brightest star in the constellation itself, is actually an eclipsing binary system. This explains its bright apparent magnitude.

Make sure to look for these asterisms during your next observing night!