The constellation Puppis rows low across the southern sky on early-spring evenings. It represents the stern of the Argo, the boat that carried Jason and the Argonauts through many harrowing adventures.
Most of the constellation’s stars are faint. In fact, its leading light barely ranks among the 70 brightest stars of the night sky.
In most constellations - especially those from the ancient world - that star would have a name beginning with “alpha,” the first letter of the Greek alphabet, so it’d be known as Alpha Puppis. In this case, though, the star is known as Zeta Puppis - the sixth letter of the alphabet.
That naming system was devised by astronomer Johann Bayer more than four centuries ago. He generally gave the “alpha” designation to a constellation’s brightest star. The rest of the stars were labeled based on their brightness or their position in the sky.
At the time Bayer came up with his system, though, Puppis didn’t exist. Instead, it was part of the much larger constellation Argo Navis - the ship Argo.
Well after Bayer’s time, another astronomer, Nicolas de Lacaille, split Argo Navis into three constellations. Puppis represents the ship’s stern, Carina is its keel, and Vela is its sail. But Lacaille kept the Greek letter designations from Argo Navis. So Carina has the first three letters, Vela has the next two, and Puppis starts with number six - Zeta.
We’ll have more about Zeta Puppis tomorrow.
Script by Damond Benningfield, Copyright 2013
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