For a few weeks in the spring of 1764, Charles Messier was a star-cluster-discovering machine. He found five globular clusters in Ophiuchus, the serpent bearer. He cataloged them as Messier 9, 10, 12, 14, and 19.

Messier wasn’t interested in the clusters – or even in the stars. Instead, he was looking for comets. At the time, finding a comet was a way to fame and fortune. Kings offered prizes to those who found comets. And comets were named for their discoverers – a bit of immortality.

But Messier and others kept coming across fuzzy objects that resembled comets. Figuring out if they really were comets wasted time. So the French astronomer decided to compile a catalog of these distractions. He logged more than a hundred objects. They included star clusters, galaxies, stellar nurseries, and the final gasps of dying stars. Today, Messier’s list is the most famous of all astronomical catalogs.

The globular clusters all look about the same. They’re tight balls of stars. Today, we know that the typical globular contains a hundred thousand stars or more. And they’re among the oldest residents of the Milky Way – more than 10 billion years old.

Ophiuchus is a large constellation that stands well up in the southern sky at nightfall. Messier’s globulars are scattered across it. They’re all visible through binoculars – just don’t mistake them for comets.

Script by Damond Benningfield