Breakups are never quite even.

Consider the ancient constellation Argo Navis. It represented the ship that carried Jason and the Argonauts on their quest to capture the golden fleece. But it was so big that, in 1752, astronomer Nicolas Louis de Lacaille split it into three constellations: Vela, the sails; Carina, the keel; and Puppis, the poop deck — the high deck at the back of the boat.

The breakup wasn’t quite equal, though. Puppis got 40 percent of the ship’s original area. That makes it the 20th largest of the 88 modern constellations.

Puppis is a southern constellation — it’s far south of the celestial equator. That makes it tough to see from northern latitudes. From the northern half of the United States, in fact, only part of it is in view — it’s cut off by the southern horizon.

From the southern half of the country, though, Puppis rotates low across the southern sky on February nights. It nudges into view in the southeast by a couple of hours after sunset, and stands almost south by 11 p.m. or so.

A couple of moderately bright stars stand at Puppis’s upper edge. But the poop deck is best spotted by looking for Sirius, the brightest star in the night sky. Puppis is below Sirius as the constellation rises, and to the lower left of the brilliant star later on.

Puppis is home to several star clusters. Two of them are to the left of Sirius. And one of them is home to a dying star that’s blowing itself apart. More about that tomorrow.

Script by Damond Benningfield