The Argo survived many adventures. In the tale of Jason and the Argonauts, it escaped some terrible storms, the Clashing Rocks, a bombardment of huge stones, and other hazards. But it couldn’t survive the whims of astronomers. They split the Argo apart — turning the largest of all constellations into three smaller ones.

The original constellation was known as Argo Navis — the ship Argo. It was created about 3,000 years ago. According to Greek mythology, it was placed in the heavens by Poseidon, the god of the sea.

Its demise began in the mid-1700s. In a sky atlas, French astronomer Nicolas Louis de Lacaille split it into three constellations: Puppis, the poop deck — the raised deck at the back of the ship; Vela, the sail; and Carina, the keel. Lacaille said the constellation was too big and contained too many bright stars to track.

Although other astronomers began using the new constellations, many still used Argo Navis as well. It came to its end in 1930, when astronomers adopted 88 official constellations. So the stellar Argo met its fate not on the high seas, but on a list compiled by astronomers.

Puppis is the largest of the surviving bits of the Argo. It sits atop the southern horizon as night falls. It’s to the lower left of Sirius, the brightest star in the night sky. Vela follows it a little later. But from most of the U.S., Carina stays below the horizon and out of sight.

We’ll have more about Puppis tomorrow.

Script by Damond Benningfield

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