One of the joys of amateur astronomy is the thrill of spotting deep-sky objects with just a pair of binoculars or a small telescope. One such gem is Messier 7 (M7), also known as the Ptolemy Cluster, a stunning open cluster nestled in the constellation Scorpius. If you’ve ever scanned the southern sky on a warm summer night, you may have unknowingly passed over this beautiful collection of stars.

A Brief History
M7 has been known since antiquity and was first recorded by the Greek-Egyptian astronomer Claudius Ptolemy around 130 CE. Charles Messier later cataloged it in 1764, adding it to his famous list of deep-sky objects. It remains one of the brightest and most striking open clusters visible to the naked eye, making it a favorite target for stargazers.

Finding M7
M7 is located in the tail of Scorpius, near the bright star Shaula. If you trace the curve of the Scorpion’s body down toward its stinger, M7 appears as a hazy patch to the naked eye under dark skies. With binoculars, its true nature becomes clear—a sprawling group of bright stars spread across a wide field of view.

What You’ll See
Through binoculars, M7 is a magnificent sight, displaying dozens of stars arranged in a loose but distinct pattern. A small telescope reveals even more detail, showing over a hundred stars scattered across a 25-light-year span. The cluster lies about 980 light-years from Earth and is estimated to be around 200 million years old—a relatively young age in cosmic terms.

Best Time to Observe
M7 is best viewed in summer when Scorpius is high in the southern sky. The ideal months for observation are June through August, with the best views occurring from dark-sky locations away from city lights. Since M7 is relatively low in the sky for northern observers, a clear southern horizon is essential for a good view.

A Reminder of Cosmic Wonder
The Ptolemy Cluster is a reminder of how rewarding amateur astronomy can be. It doesn’t require advanced equipment to enjoy its beauty—just a clear night, some patience, and a love for the night sky. Whether you’re using binoculars, a small telescope, or simply your eyes, M7 is a dazzling example of the wonders awaiting discovery above us.