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CALIFORNIA WILD

 

SKYGUIDE

January to March 2005

January 1: Happy New Year! Earth at perihelion, its closest point to the Sun, during Winter in the Northern Hemisphere, showing that Earth's seasons are not the result of our distance from the Sun, but the angle of incoming sunlight.

January 3: Peak of the Quadrantid meteor shower this morning, with about 40 meteors per hour. Not well known in the Northern Hemisphere because it occurs on a cold winter night.

January 10: New Moon at 4:03 am. (All times Pacific Standard Time.) The young, crescent Moon will be 13 hours old at sunset tonight (5:09 pm)-not quite visible without binoculars. Tomorrow night, the unquestioned naked-eye sighting of the crescent Moon will mark the start of Zul-Hijjah, the 12th month of the lunar-based Islamic calendar.

January 25: Full Moon at 2:32 am. Also called the "Wolf Moon" or the "Old Moon" by the Algonquin, the "Cooking Moon" by the Choctaw, and the "Hunger Moon" by the Osage.

February 8: New Moon at 2:28 pm. The New Moon closest to the Spring Equinox usually marks the start of the Chinese New Year (also called the Lunar New Year or the Spring Festival). So why do calendars say Chinese New Year is tomorrow, rather than today? Because the new year is reckoned by China's time zone, which is 15 hours ahead of Pacific Time. Tomorrow's sighting of the first crescent marks the start of the month of Muharram and the start of the Muslim year. The lunar calendar is eleven days shorter than the 365-day solar calendar, so Muslim holidays occur eleven days earlier from one year to the next and are not linked to particular seasons.

February 23: Full Moon at 8:54 pm, rising at sunset. The Dakotah Sioux called this the "Moon of the Raccoon," the Lakota Sioux called it the "Moon of the Dark Red Calves," and the Kutenai and Tlingit called it the "Black Bear Moon."

March 10: New Moon at 1:10 am. At sunset tonight (6:13 pm pst), the Moon will be 17 hours old for West Coast observers and should be just visible as an extremely thin crescent very low in the west. Muslims use this sighting to mark the beginning of the month of Safar.

March 20: Equinox (beginning of Spring in the Northern Hemisphere and of Fall south of the equator) at 8:33 am. The Sun rises due east and sets due west. Day and night are theoretically of equal length.

March 25: Full Moon at 12:58 pm, but not visible until it rises at sunset. Since this is the first Full Moon of Spring, Western tradition calls for Easter to fall on the following Sunday, March 27. To the Ponca, this was the "Sore-Eyes Moon" (from snow-blindness), to the Algonquin, it was the "Sap Moon," and to the Natchez, it was the "Deer Moon."

The Planets

Mercury: In January (the earlier in the month the better), look for Mercury and brighter Venus close together low in the east before dawn. They gradually rise later and later until they disappear in the glow of the rising Sun. On the morning of January 8, the crescent Moon is about 8 degrees to the right (less than the width of your fist at arm's length), while Mercury and Venus are spectacularly close together. Mercury is hidden by the Sun's glow until it emerges in the evening sky in late February. Then it will be visible low in the west after sunset. In early January, be sure to try to see five naked-eye planets stretched across the predawn sky-the last opportunity to see them all simultaneously until 2016!

Venus: Visible only in January, Venus is a brilliant predawn object, rising before the Sun but appearing lower and lower each morning. Late in the month, it disappears in the Sun's glow. It makes a close approach to Mercury on the morning of January 9, rising about 80 minutes before the Sun. The crescent Moon swings nearby on the mornings of January 8 and 9.

Mars: Visible in the southeast in the predawn sky, the "Red Planet" moves quickly from the stars of Scorpius, through the foot of Ophiuchus, and into Sagittarius and Capricornus. In early January, it's near Antares, the Scorpion's heart and the star named after it (Antares-rival of Mars). The waning crescent Moon passes nearby on the mornings of January 7, February 5, and March 6.

Jupiter: The largest planet loiters against the stars of Virgo all season, hovering near the star Spica. It rises just after midnight and is high in the south at dawn. Through March, it can be seen gradually lower in the west each dawn, with the Moon passing by on January 3 and 31, February 27, and March 26.

Saturn: The "Ringed Planet" is the only other world visible in the early evening sky this season, and it rises against Gemini about an hour after sunset. By midnight, it's very high in the south. The Moon is close by on January 23, when both rise together at sunset; February 19 and 20, when both are about halfway up the sky at sunset; and March 18 and 19, when both are very high in the south just after sunset. Watch media reports for news from the Cassini spacecraft orbiting Saturn and (hopefully) from the Huygens lander as it descends to the surface of the moon Titan in mid-January.

  Sunrise Local Noon Sunset
January 1 7:25 AM PST 12:13 PM PST 5:01 PM PST
February 1 7:14 AM PST 12:23 PM PST 5:33 PM PST
March 1 6:40 AM PST 12:22 PM PST 6:04 PM PST
April 1 5:54 AM PST 12:14 PM PST 6:33 PM PST

Times are for San Francisco, CA, and are accurate to within two minutes.

A Hybrid Solar Eclipse

On April 8, an unusual solar eclipse will occur. The Moon will pass between the Earth and the Sun, casting its shadow on the Earth. During this event, the curvature of the Earth will make enough of a difference in the Moon's appearance that the type of eclipse will change depending on where observers are located. The eclipse will be total over the Pacific, with the Moon completely blocking the Sun's disk from view. This reduces the Sun's glare enough that our star's ghostly corona--or outer atmosphere--can be seen. As seen from the ends of the shadow-path--including where it finally touches land in Costa Rica, Panama, Colombia, and Venezuela--the Moon won't quite conceal the Sun's disk, so the eclipse will be annular. A visible ring of the Sun's disk (or annulus) will be bright enough to wash the corona from view. Away from the shadow-path, observers in the southern United States, Central America, the Caribbean, and most of South America will see a partial eclipse.



Bing F. Quock is a member of the Morrison Planetarium staff at the California Academy of Sciences. bquock@calacademy.org