Download Constellation Argo Navis

CONSTELLATIONS OF THE SOUTHERN SKY
Argo Navis (or simply Argo) in antiquity was a large
constellation in the southern sky that has since been divided into
three constellations. It represented the Argo, the ship used by
Jason and the Argonauts in Greek mythology.
Argo Navis is the only one of the 48 constellations listed by the
2nd century astronomer Ptolemy that is no longer officially
recognised as a constellation. It was unwieldy due to its enormous
size: were it still considered a single constellation, it would be the
largest of all. In 1752, the French astronomer Nicolas Louis de
Lacaille subdivided it into Carina (the keel, or the hull, of the
ship), Puppis (the poop deck, or stern), and Vela (the sails).
More of those below. The constellation Pyxis (the mariner's
The constellation Argo Navis drawn by
compass) occupies an area which in antiquity was considered part
Johannes Hevelius
of Argo's mast (called Malus). However, Pyxis is not considered
part of Argo Navis, and its Bayer designations are separate from
those of Carina, Puppis and Vela.
The Argonauts were a band of heroes in Greek mythology, who in
the years before the Trojan War, accompanied Jason to Colchis in
his quest to find the Golden Fleece. Their name comes from their
ship, the Argo, named after its builder, Argus. "Argonauts"
literally means "Argo sailors". The story goes as follows:
After the death of King Cretheus, the Aeolian Pelias usurped the
Iolcan throne from his half-brother Aeson and became king of
Iolcus in Thessaly (near the modern city of Volos). Because of this
unlawful act, an oracle warned him that a descendant of Aeolus
would seek revenge. Pelias put to death every prominent
descendant of Aeolus he could, but spared Aeson because of the
Gathering of the Argonauts, 460–450 BC
pleas of their mother Tyro. Aeson married Alcimede, who bore
Louvre (G 341
him a son and smuggled the baby to Mount Pelion where he was
raised by the centaur Chiron, who called the boy Jason.
When Jason was 20 years old, an oracle ordered him to head for the Iolcan court. Pelias recognized that Jason
was his cousin. He could not kill him because prominent kings of the Aeolian family were present. Instead, he
asked Jason: "What would you do if an oracle announced that one of your fellow-citizens were destined to kill
you?". Jason replied that he would send him to go and fetch the Golden Fleece (words that the goddess Hera
had put in his mouth). Pelias was secretly being haunted by the ghost of Phrixus, who had once fled from Iolcus
to Colchis to avoid being sacrificed, riding on a golden ram. According to the oracle, Iolcus would never
prosper unless the golden ram's fleece was brought back to Iolcus. This fleece now hung from a tree in the
grove of the Colchian Ares, guarded night and day by a dragon that never slept. Pelias swore before Zeus that
he would give up the throne at Jason's return, firmly expecting that Jason's attempt to steal the Golden Fleece
would be a fatal enterprise. However, Hera acted in Jason's favour during the perilous journey.
Jason was accompanied by some 50 principal heroes of ancient Greece, including the well-known figures of
Hercules, Orpheus and Perseus. When they reached Colchis, Jason
asked the King Aeëtes of Colchis for the Golden Fleece. The King did not
refuse, but imposed severe conditions, such as plowing a field with firebreathing bulls and sowing it with dragons teeth. Jason had attracted the
attention of Medea, the daughter of the king. She helped him by magic,
having made him promise to marry her and take her to Greece. With the
help of her magic he was able to do all that and even steel the Golden
Fleece from the dragon guarding it.
When the Argonauts fled from Colchis, Medea took along her young
brother, but murdered him to slow the pursuit of her father. This evil
deed caused the gods to send the Argonauts on a geographically
confusing trip around Italy and various other places, before Jason could Medea statue holding the Golden Fleece in
the center of Batumi (one of the major cities
go home and with the fleece claim his rightful place as King of Iolcus.
of Colchis), Georgia
Some have hypothesized that the legend of the Golden Fleece was based on a
practice still used today by Black Sea tribes, placing a lamb's fleece at the
bottom of a stream to entrap gold dust being washed down from upstream. The
Argo was built by the shipwright Argos or Argus. It was built at the port of
Pagasae, using timber from nearby Mount Pelion. Most of what we know about
the Argo comes from the Greek poet Apollonius Rhodius, 3rd century B.C.
from his epic poem, TheArgonautica
The Modern Picture of the Argo:
Carina is the keel of the ship, the very bottom of the ship's hull, the ship's
backbone. Two asterisms are prominent in Carina. One is known as the
Diamond Cross, which is larger than the Southern Cross (but fainter), the
long axes of the two crosses being close to parallel. The other is the False
Cross, often mistaken for the Southern Cross. The False Cross consists of two Apollonius of Rhodes, floruit first
stars in Carina, Iota Carinae and Epsilon Carinae, and two stars in Vela, Kappa half of 3rd century BCE, is best
known as the author of the
Velorum and Delta Velorum. Carina is well-known for its namesake nebula,
Argonautica, an epic poem about
NGC 3372, discovered by French astronomer Nicolas Louis de Lacaille in
Jason and the Argonauts and their
1751. The Carina Nebula overall is a colossal emission nebula approximately quest for the Golden Fleece.
8,000 light-years away and 300 light-years wide that possesses vast
star-forming regions; it has an overall magnitude of 8.0 and a massive apparent
diameter, more than 2 degrees. Its central region is called the Keyhole Nebula,
named in 1847 by John Herschel. It is about seven light-years wide and is
mostly made up of ionized hydrogen, with two major star-forming regions. The
Homunculus Nebula is a planetary nebula visible to the naked eye that is being
ejected by the erratic luminous blue variable star Eta Carinae, the most massive
visible star known. Eta Carinae is so massive that it has reached the theoretical
upper limit for the mass of a star and is therefore unstable. It is known for its
outbursts; in 1840 it briefly became one of the brightest stars in the sky due to a
particularly massive outburst, which largely created the Homunculus Nebula.
Because of this instability and history of outbursts, Eta Carinae has reached the end of its estimated million-year
life span and is considered a prime supernova candidate in the next several thousand years. Since the Milky
Way runs through Carina, there are a large number of open clusters in the constellation, embedded in rich star
fields. The most prominent is IC 2602, also called the "Southern Pleiades". Carina also is the radiant of the
Eta Carinids meteor shower, which peaks around January 21 each year.
Puppis is the Stern or the poop deck of the Ship Argo Navis. Puppis is from Latin
puppis, a standard word for 'ship', but technically it refers to the rear deck of the
ship which is the poop deck, the afterpart of a ship. Several extrasolar planet
systems have been found around stars in the constellation Puppis. As the Milky
Way also runs through Puppis, there are a large number of open clusters in the
constellation. M46 and M47 are two open clusters in the same binocular field.
M47 can be seen with the naked eye under dark skies, and its brightest stars are 6th
magnitude. Messier 93 (M93) is another open cluster somewhat to the south. NGC
2451 is a very bright open cluster containing the star c Puppis and the near NGC
2477 is a good target for small telescopes. The star Pi Puppis is the main
component of a bright group of stars known as Collinder 135.
The word Vela comes from the Indo-European root for the weblike part of a
feather; the vane, curtain or veil. The brightest star in the constellation (sometimes
called Regor) is a bright 1.75m supergiant star. The star is actually quintuple, and
the primary component is famous for being the brightest Wolf–Rayet star in the
sky. The discovery of a binary brown dwarf system named WISE 1049-5319 only
6.6 light years away, the third closest system to Sol, was announced on 11 March
2013. Also of interest is the Vela Supernova Remnant. This is the nebula of a
supernova explosion which is believed to have been visible from the Earth around
10,000 years ago. The remnant contains a pulsar which was the first pulsar to be
identified optically.
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