November night sky diagram

Night Sky November 2005

—CHARLIE CHRISTMANN

MARS
Mars is the talk of the night sky this month. Look east late these evenings and you'll see a big fiery "star" shining much brighter than any other. This is the planet Mars, and it's passing unusually close to Earth during late October and early November 2005. Anyone can see it no matter how little you know about the stars or how badly light-polluted your sky may be. Mars will be its closest to Earth on the night of October 29-30, just 43.1 million miles from our planet. This is the nearest that Mars has come since its record-breaking close approach in August 2003.

Surface details on Mars are always a pretty tough target in a telescope. You'll need at least a moderate telescope with high-quality optics to have much luck. To begin with, Mars is only about half the size of Earth. Even at its closest, under high magnification it will appear as only a surprisingly small, bright ball with some subtle dark markings, possible white clouds around its edges, and perhaps a tiny remnant of the white south polar cap shrunken in the warmth of the Martian summer. The brightest yellow areas are deserts covered by fine windblown dust. The darker markings are terrain displaying more areas of bare rock or darker sand and dust. Mars rotates every twenty-four hours, so you can see it turning in just an hour or two of watching.

ZODIAC
The one set of constellations everyone knows by name are all members of the Zodiac.

Thousands of years ago, objects in the sky were believed to be affixed to transparent celestial spheres, and their motions were thought to be a result of the motion of these spheres as they revolved around the Earth. Groups of bright stars were observed to form patterns in the night sky called constellations, which have been historically ascribed to mythological figures, such as Orion the Hunter, and Gemini the Twins. The early astronomers recognized that constellations "appeared" and "disappeared" with the change of the seasons throughout the course of a year. The Sun, Moon, and planets were seen to move in relation to the fixed background of stars, or constellations. Because of their perspective from Earth, early astronomers observed that all the planets visible with the naked eye, as well as the Sun, seemed to pass in the course of a year through a region in the sky occupied by twelve specific constellations.

More than three thousand years ago, astronomers wondered how the sky would appear if the stars could be seen during the daytime. Based on their observations of the night sky, some astronomers determined that during the daytime, the Sun would appear to "enter" or pass through a different constellation each month. These twelve constellations are called the zodiac: Aries (the ram), Taurus (the bull), Gemini (the twins), Cancer (the crab), Leo (the lion), Virgo (the virgin), Libra (the balance), Scorpio (the scorpion), Sagittarius (the archer), Capricornus (the goat), Aquarius (the water bearer), and Pisces (the fishes).

The zodiac constellations, as envisioned by ancient astronomers, were assigned to specific patterns that resemble the shapes of animals, half-animals, and human beings. The constellations of the zodiac actually form an imaginary belt in the sky that extends about eight degrees above and below the plane of the ecliptic.

In reality, there are thirteen zodiac constellations. If you were born between the first and fifteenth of December, then your star sign is not Sagittarius, as you thought, but Ophiuchus. Ophiuchus is the thirteenth constellation through which the sun passes, but it isn't included on astrological calendars.

And if the thirteenth sign isn't alarming enough to an astrologer, the twelve zodiac signs don't match the actual positions of the constellations in today's sky. The reason is that while the earth spins once in twenty-four hours, it also has other movements. Just like a spinning top, the earth has a slow wobble, called precession, as it spins. It's really slow, taking twenty-six thousand years to do one wobble. This causes the zodiac constellations to drift through the sky. The Egyptian and Greek astrologers chose signs that more or less matched the constellations. But, because of precession, the moving constellations have left the signs far behind. Today they are seriously out of step by about one sign. For example, if you were born the first part on November, your sign astrological is Scorpio. The actual sign by the position of the Sun and the stars today would be Libra.

The drift in signs will only get worse over the next few thousand years, but will realign again in about twenty-two thousand years.

THE PLANETS AND THE MOON

• Mercury is a morning planet early in the month, but may be seen very low on the horizon. Look for it low on the western horizon on November 3 at 7:00 p.m. near the Moon.

• Venus is in the evening sky all month. Look for the crescent Moon between Venus and Mercury on November 4 just after sunset.

• Mars reaches opposition on November 7 and shines at a brilliant -2.1 magnitude. Look for Mars in the eastern evening sky.

• Jupiter is missing from the night sky until late in the month, when it slowly emerges in the morning sky.

• Saturn rises about midnight and shines in the south at dawn.

• The Moon is new on November 1 and full on November 15.

Charlie Christmann will be leading a discussion and a Night Under The Stars on November 3, beginning at 7:00 p.m., at the Placitas Library. Participants should bring jackets and binoculars.

Astrophotography exhibition opens

The LodeStar Astronomy Center and The Albuquerque Astronomical Society have opened the fourth annual "Astro-Images of New Mexico: Portraits from the Foothills of Space" astrophotography-contest exhibition.

The exhibition, a celebration of the beauty of the New Mexico sky, features twenty-nine celestial images taken throughout the state of New Mexico by amateur photographers. Images were submitted in four categories: Land & Sky, Plate/Film/Digital, Photo Illustration, and CCD (very light-sensitive digital imaging).

Jim Gale, of Albuquerque, was awarded best of show for Windows to the Sky, his image of star trails over Ventana Arch in El Malpais National Monument. "It's essentially a simple star-trail time exposure using the arch to create the impression of windows opening towards the sky," said Gale. He added, "To help add a more earthly and familiar context to the image, I chose to photograph on nights when the moon would light part of the arch to show both the texture and structure of the sandstone."

The images will be on display through February 28 at the LodeStar Astronomy Center, located in the New Mexico Museum of Natural History and Science, in Old Town Albuquerque. The exhibit is open daily from 9:00 a.m. to 5:00 p.m. and is included with LodeStar or museum admission. For further information, call (505) 841-5955 or visit www.lodestar.unm.edu or www.taas.org.