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Evil Twin Brother

Xolotl Xolotl

By Ellis Myers

The Aztec, as did the Toltec and the Maya, revered Quetzalcoatl as the god of science and learning as well as of re-birth and butterflies. Quetzalcoatl took part in both the creation of the universe and the invention of culture, including the discovery of fire, agriculture, science, and the arts. Quetzalcoatl had a twin brother whose name was Xolotl. As lord of the evening star he pushes the sun at sunset towards the ocean and guards her during the night on her dangerous journey through the underworld. The evil twin, he was feared as the god of lightning.

In legend, Quetzalcoatl descended into the underworld where he outwitted the god of the dead and rescued mankind from the power of death. He then ascended into heaven, where he became Tlahuizcalpantecuhtli, the morning star (Venus). Temples dedicated to Quetzalcoatl were erected in many cities throughout Mesoamerica, such as at Chichen-Itza and at Tula. Ceremonies and rites were linked to the astronomical phases of Venus. The Mayan and Aztec calendars were, in part, based on observations of Venus, observations that were extremely precise.

The story of Quetzalcoatl has two different endings. In one, Quetzalcoatl sacrifices himself on a funeral pyre, ascending into heaven to become the morning star Venus. In another, he sails off into the sea toward the east, promising to return one day and restore his kingdom. When Cortez and the Conquistadors arrived in Mexico in 1517, the Aztec king Montezuma was convinced that the Spaniard was Quetzalcoatl, returning as he had promised. In awe, Montezuma presented treasures to Cortez and invited him to take control of the land. The Spanish conquest of Mexico was therefore due in part to the belief of the Aztecs that Quetzalcoatl would one day return as promised.

Xolotl—the Evening Star—is in command this month and next, until he, himself, follows the sun into the western sea.

Amateur astronomers who wish to observe Venus have options ranging from enjoying the brilliance of the planet just with the naked eye, or studying the phase with good binoculars or a small telescope. Or they may choose to do significant scientific record keeping in association with the Venus section of ALPO, the Association of Lunar and Planetary Observers. This group has listed its goals for study as follows:

1. Visual observation and categorization of atmospheric details in dark, twilight, and daylight skies.
2. Drawings of atmospheric phenomena.
3. Observation of cusps, cusp-caps, and cusp-bands, including defining the morphology and degree of extension of cusps.
4. Observation of dark hemisphere phenomena, including monitoring visibility of the Ashen Light.
5. Observation of terminator geometry (monitoring any irregularities).
6. Studies of Schroter's phase phenomenon.
7. Visual photometry and colorimetry of atmospheric features and phenomena.
8. Routine photography (including UV photography), CCD imaging, photoelectric photometry, and videography of Venus.

More information is available at their web site: www.lpl.arizona.edu/alpo/.

Venus has now entered the constellation Pisces where it will remain until June. It will disappear into the sun's preeminence by the end of March, then to reappear in the morning sky—as Quetzalcoatl, not Xolotl.

We will see the planet at its Greatest Illuminated Extent on February 22, the moment when the planet’s apparent sunlit area is maximized. This new term, GIE, is not the same as maximum brightness, however. While for Venus, the dates of these two disparate events are only a few days apart at most; for the planet Mercury, the difference may be as long as a few weeks.
In February, Venus does reach a magnitude of –4.62, more than 18 times as bright as Sirius, the brightest of all stars. As it continues its orbit around the sun it draws closer to us, but turns its face toward the sun (until the point of inferior conjunction*). This effect is illustrated in the drawing, comparing the apparent size of the illuminated disk at greatest eastern elongation on January 17, on February 22, and four weeks later on March 22. The enclosing reference circles are drawn at a diameter of one minute of arc.

When it reappears in the morning sky, Venus will regain its brilliance to magnitude –4.5 in early May before slowly fading as the distance between the two planets then increases. The entire cycle—the length of time between one encounter of Venus with Earth to the next—is 584 days, or just over 19 months. This Spring, then, is your best opportunity for admiring our planet's "evil twin" until September, 2002.

*When Venus or Mercury lie nearly between the Earth and the Sun. Britannica.com

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