| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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SKYGUIDE October to December 2004
October 8: Peak of the modest but variable Draconid meteor shower, observed to radiate from the constellation Draco. Formed by a rain of dust from Comet Giacobini-Zinner, this shower is also referred to as the Giacobinid meteors. October 13: New Moon at 7:47 pm. But if the crescent can't be seen until the evening of the 15th, Muslims will use that to mark the start of Ramadan. In Alaska, the New Moon passes directly in front of the Sun, causing a partial solar eclipse: 93 percent of the Sun's diameter is blocked out. October 21: Peak of the Orionid meteor shower, caused by dust from Halley's Comet. It produces around 25, usually faint, meteors per hour. October 27: Tonight's Full Moon, the "Hunter's Moon," rises about sunset. The Full Moon generally emits eleven times more light than the quarter moon. On the West Coast, the Moon rises just minutes after a total lunar eclipse starts. Watch as Earth's shadow slowly creeps across the Moon's face, completely covering it at 7:23 pm. October 31: Change from Daylight Saving Time to Standard Time. Clocks are set back one hour officially at 2:00 am. The country gains an extra hour of sleep-except for American Samoa, Hawaii, most of Arizona, part of Indiana, Puerto Rico, and the Virgin Islands. November 12: New Moon at 6:25 am. At sunset tonight (5:00 pm), the Moon is ten hours old-too young to be seen. The youngest crescent seen with the unaided eye is 15 hours old, and with a telescope you can see it at just over twelve hours old. When it's seen tomorrow night (the 13th), Muslims mark Eid-al-Fitr, the start of the month Shawwal. November 17: Peak of the Leonid meteor shower. Though quite spectacular in recent years, it is expected to subside to about 15 meteors per hour. Slamming into Earth's atmosphere head-on, these bright meteors typically travel 45 miles per second; at least half of them leave glowing trails November 26: Full Moon, also known to the Algonquin as the "Beaver Moon," to the Natchez as the "Bison Moon," and to the Osage as the "Raccoon Breeding Moon." December 11: New Moon at 5:28 pm. Look tomorrow night (the 12th) after sunse t for the first visible crescent. This marks the start of Zul-Qa'dah, the eleventh month of Islam. December 13: Peak of the Geminid meteor shower, usually the year's best, with about 50 meteors per hour-although few people tend to be out stargazing on long, cold winter nights. This year the shower coincides with a very thin, two-day old crescent. Though the meteors can appear anywhere in the sky, their trails appear to radiate from the direction of the constellation Gemini. December 21: Winter solstice at 4:40 am. The Sun rises and sets at its most southerly points on the horizon and makes its lowest and shortest arc across the sky. South of the Equator, this is the Summer solstice, and days start growing shorter. December 22: Peak of the Ursid meteor shower, a weak display of usually about ten meteors per hour radiating from near the star Kochab in the Little Dipper. December 26: Full Moon, also sometimes known as the "Moon of the Popping Trees" to the Lakota Sioux, evoking images of less-than-balmy weather. Notice how high this Full Moon crosses the sky compared to the Winter Sun. The Planets Mercury: The speediest of the planets makes a quick appearance in the evening sky in November, rising out of the Sun's glow at a shallow angle that makes observation difficult. Quickly darting back into the twilight, it vanishes for awhile but reappears in the morning sky by mid-December. The Moon passes by on November 13. Venus: This dazzling planet dominates the predawn sky all season. As it gradually rises later and later, apparently descending into the glow of the rising Sun, watch two other planets ascend toward it and pass by: Jupiter on November 4, and Mars on December 4. The waning crescent Moon sweeps nearby on the mornings of October 10, November 9 and 10, and December 9. Mars: Just emerging from the twilight, the Red Planet slowly ascends into the morning sky, rising in the east before dawn. It becomes easier to see by late October as it climbs ponderously toward brighter Venus and Jupiter. It never catches up to Jupiter, but Mars and Venus meet up and form a pretty pair on the morning of December 4. Watch for the Moon to pass nearby on the mornings of November 10 and 11, and December 9. Jupiter: Like Mars, Jupiter is low in the east at dawn at the beginning of the season, but gradually rises earlier each morning. The largest planet is also one of the brightest in the sky. A small telescope or tripod-mounted binoculars will allow observers to see its four largest moons. Watch Jupiter approach to within a degree of Venus on the mornings of November 4 and 5. The Moon can be seen nearby on the mornings of October 12, November 9, and December 7. Saturn: Approaching a January opposition, the Ringed Planet is becoming easier to see: located in Gemini, Saturn rises around 1:00 am at the beginning of October, by about 10:00 pm at the beginning of November, and-conveniently-by 8:00 pm at the beginning of December. Even small telescopes reveal the planet's magnificent rings and its largest moon, Titan (see below).
Times are for San Francisco, CA, and are accurate to within two minutes.
Bing F. Quock is a member of the Morrison Planetarium staff at the California Academy of Sciences. bquock@calacademy.org |