August 5th, 2013
Canopus now belongs to the constellation Carina, the Keel, but the Keel was once part of Argo Navis, the Ship Argo. Provided a berth in the night sky as one of the 48 constellations cataloged by the Alexandrian astronomer Ptolemy, the starry Ship is now dry-docked and dismantled. In 1763, the French astronomer Nicolas-Louis de Lacaille split the old galley into several pieces for the convenience of more modern astronomy.
Canopus has been getting keelhauled at least since the third century B.C., when Aratus, the author of the oldest handbook of the heavens we’ve inherited from ancient Greece, called this star the Ship’s pedalion, or rudder. It hangs loose, he added, beneath the hind legs of Canis Major, the Great Dog. Identifying the ship by name, Aratus confirmed that this celestial vessel once transported Jason and his all-star crew of Argonauts to Colchis on the eastern shore of the Black Sea in the quest for the Golden Fleece. Later this year, several cruise ships will be following the wake of the Argo through the Bosporus on a quest for coronal fleece in a total solar eclipse that includes the Black Sea in an August 11th argosy of darkness.
Although Aratus did not use the name Canopus for the star in the Ship’s rudder, that name does appear in the Catasterismi. Its celestial myths probably reflect star lore of the same era. Canopus is not mentioned, however, in the Catasterismi’s chapter on Argo. It appears instead in the passage on Eridanus, the River. Placed below the River, Canopus “touches the steering-oars of the Argo.” The Catasterismi additionally suggests that Eridanus represents the Nile. The Roman mythographer Hyginus also identified Eridanus as the Nile, assigned Canopus to it, and described the star as “an island washed by the Nile river.”
A star as bright as Canopus understandably commanded attention in other parts of the world. Most of China could see it, and in China it was known as Shou xing, the Star of Longevity. Its southern disposition also prompted the Chinese to call it “The Old Man of the South Pole,” and China’s first emperor, Qin Shi Huang Di, offered sacrifices to it. Later, Canopus was personified as a cheery and bald old man who travels with a big peach, a symbol of long and rich life.
In New Zealand the Maori watched for the first predawn return of Canopus as a signal of the coming frost. They named it Atutahi and remembered its use by their migrating ancestors to navigate the Pacific from eastern Polynesia. Wilhelm H. I. Bleek and L. C. Lloyd included ideas about Canopus among the San people of South Africa in Specimens of Bushman Folklore (1911). The San sang to the star in winter and burned a stick toward it to coax a little more heat from the Sun. They associated Canopus with Sirius and said the two wink similarly.
Of course, you don’t have to travel as far south as New Zealand, South Africa, or even Alexandria to catch Canopus. If you are moored anywhere south of 37[degree sign] north latitude, you can spot it at this time of year.
Precession doesn’t alter the declination of Canopus very much. Located fairly close to the south pole of the solar system, it is more or less anchored in the current that shifts the stars’ positions in a 26,000-year cycle. Its visibility from places like Athens, Alexandria, and Rhodes hasn’t changed much in 2,000 years.
From Rome, too, Canopus still enjoys roughly the same level of southern hospitality it did when Vitruvius Pollio was compiling his 10 books of De architectura. Explaining how some constellations circle the south celestial pole and remain hidden beneath the ground from Rome, he wrote, “The star Canopus proves this. It is unknown to our vicinity; but we have reports of it from merchants who have been to the most distant part of Egypt, and to regions bordering on the uttermost boundaries of the earth.”
For the Romans, Canopus was almost synonymous with Egypt. In fact, a famous town with that name once operated as a Mediterranean port for the westernmost branch of the Nile. By legend, Canopus was named for the pilot who was shepherding King Menelaus and Helen back home. Their ship was driven by storm to the Egyptian coast, and thanks to a viper, Canopus died during shore leave. The ruins of old Canopus today are next to Abu Qar, a small village in the Nile Delta. An important council for calendar reform was convened there by Pharaoh Ptolemy III Euergetes I in 238 B.C., and the astronomer Ptolemy was headquartered there.
Canopus was just some 20 kilometers northeast of Alexandria. Operating as a pleasure spa, it also attracted pilgrims to its pagan shrines. Erotic rituals and libertine recreation helped maintain its notoriety and international appeal. Its celebrated temple to the god Serapis inspired the emperor Hadrian to build a replica in his summer retreat at Tivoli, just 26 kilometers east of Rome. Serapis was the Hellenistic version of Osiris, the Egyptian god who presided over cyclical renewal. Osiris also judged and ruled the dead, and as Serapis he acquired attributes of several Greek gods, including a talent for healing.
There is a puzzle in all this Canopus lore. According to the Greeks, the constellation Argo was Jason’s ship, and the star that marked its rudder was named for a legendary helmsman. Canopus, however, never sailed on the Argo. When the poet Pindar recited the ship’s roster in the first half of the fifth century B.C., Canopus didn’t make the list. Apollonius of Rhodes, who in the third century B.C. authored the most enduring account of the Argo’s adventures, said the ship’s first pilot was Tiphys.
Canopus was not shanghaied for an Argo tour of duty until later, in the first century B.C., when Greek writers like the geographer Strabo conscripted Canopus into the crew. In the earlier Greek star tales, however, Canopus was associated with Egypt. This connection with Egypt was later reinforced by the reassignment of a veteran of the Trojan War to Jason’s quest. Maybe we should be looking toward Egypt to understand how Canopus was insinuated into Greek astronomy.
Plutarch documented his understanding of the Egyptian gods in Isis and Osiris, and he reported the Egyptian belief that the star Canopus was named after the pilot who guided the ship of Osiris. The ship, he added, is the constellation Argo. Although we can’t independently verify Plutarch’s astronomical analysis, other information he provided about Egyptian gods and stars is supported by Egyptian antiquities. If Plutarch was right, this element of Egypt’s astral mythology may have been borrowed by the Greeks and reconfigured to commemorate their maritime adventures. By the time the stellar Ship had become known as Argo, constellational consistency enlisted Canopus to steer the Argonauts.