|
Translate this page into:
         
|
Following the mighty Orion across our wintry night sky is the constellation of Gemini, the twins. According to Greek myth the twins were actually quadruplets, born of Leda, wife of Tyndareus. One night the ever lustful Zeus (Jupiter), king of the gods, came to Leda in the form of a swan, and seduced her. Her husband also came to her that night, and nine months later Leda gave birth first to an egg, the result of her union with Zeus, from which emerged Pollux (the pugilist, or boxer), and a sister, who was to become Helen of Troy, both immortal offspring of Zeus. Then Leda gave birth to her husband's mortal progeny: Castor (the horseman), and Clytaemnestra, who became the wife of King Agamemnon, the king who went to war with Troy.
As twin brothers, Castor and Pollux were inseparable. They shared many adventures, including sailing with Jason and the Argonauts in search of the Golden Fleece. When Castor was killed in a fight, Pollux was so filled with loss that he begged his father, Zeus, to take away his immortality, so that he might die, and be with his brother. Zeus was so moved by this display of love and loyalty he not only granted the wish of Pollux, he placed their forms in the heavens, as a testament to the strength of brotherly love. It is also written that Zeus's brother, Poseidon (Neptune), was so moved he granted the twins power over the winds and the waves, so that sailors for centuries have worshiped the twins, and invoked their mercy on the high seas. Shelly writes,
St. Elmo's Fire (an electrical glow that sometimes occurs in the rigging of ships during storms), was known as Ledaean Lights, after the twins' mother, Leda, and the phrase, by jimminy, actually comes from the ancient sea faring vow, by Gemini !
The twins even appear in the Bible. In Acts 28:11 Paul the apostle writes, "And after three months we departed in a ship of Alexandria, which had wintered in the isle, whose sign was Castor and Pollux."
Although Castor is designated as the alpha star in the constellation, it is actually the dimmer of the twins, with a magnitude of 1.59, leading to speculation that the star was brighter in ancient times. Although Castor appears as a single star to the naked eye, it is actually one of the most complex multiple star systems in the sky, consisting of no less than six separate stars, organized into three binary systems, gravitationally bound to each other. The Castor system is 45 light years from Earth.
Pollux is the brighter of the two twins, with a magnitude of 1.16, making it the 17th brightest star in the sky. Pollux is a K0 yellow giant, 11 times larger than the Sun, with a surface temperature of 4500 °C. It is 35 light years from Earth.
These two star clusters are located within the same field of view, and are a fine sight in a backyard telescope. The larger, sparser cluster on the left, M35, is 2,000 light years away, and the smaller, denser cluster to the lower right, NGC 2158, is 16,000 light years away.
NGC 2392 is known as the Eskimo Nebula, or the Clown's Head Nebula, because that's what it looks like through a small telescope. Through the eyes of the Hubble Space Telescope, as seen below, its true nature as an expanding cloud of gas left over from the explosion of a giant star (remnant of a supernova) becomes apparent.
Gemini contains another supernova remnant, discernable only in large telescopes. Below is a colour enhanced image of IC 443 from the Hubble archive.
|
|
|
|
