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CALIFORNIA WILD

 

SKYGUIDE

Marvelous Meteors

October 2 This Full Moon is also known as the “Harvest Moon.” Rising at sunset, it gave farmers enough light to continue harvesting crops after dark. The Cheyenne called it the “Moon When Water Begins to Freeze on the Edge of the Stream.”

October 16: New Moon. Tomorrow night (the 17th), look for a thin crescent low in the west after sunset.

October 21: Peak of the Orionid meteor shower, caused by Earth’s passage through the dust trail of Halley’s Comet. A keen observer might see up to 20 meteors per hour after midnight.

October 28: On the last Sunday in October, most states (except Hawaii, most of Arizona, and Indiana) return to Standard Time. Set clocks back one hour at bedtime on the night of the 27th.

October 31: Full Moon. The last time a Full Moon fell on Halloween was in 1974. This is also the second Full Moon in the same calendar month, sometimes called the “Blue Moon.”

November 14: New Moon at 10:40 p.m. pst. The lunar sighting on the 15th marks the start of Ramadan, the Muslim month of fasting.

November 17: Peak of the annual Leonid meteor shower, which has been exceptionally spectacular in recent years. (See box.)

November 30: Full Moon. Known to the Algonquin as the “Beaver Moon” and to the Cheyenne as the “Freezing Moon.”December 13 Peak of the Geminid meteor shower, usually the year’s most reliable—about 50 meteors per hour.

December 14: New Moon. An annular solar eclipse, with the Sun appearing as a bright ring around the dark Moon, is mostly visible from the Pacific Ocean. Observers in San Francisco will see only a partial eclipse of 15 percent of the Sun’s diameter at 8:54 a.m. pst. From land, the annulus ring will be visible only in Costa Rica and the southern tip of Nicaragua.

December 21 Winter Solstice at 11:20 a.m. pst. The North Pole is tilted its farthest away from the Sun.

December 30: Full Moon. A penumbral lunar eclipse peaks at 2:29 a.m. pst. The Moon skims the outer edge of Earth’s shadow, so the Moon’s southern half might appear darkened.

The Planets

Mercury starts October as an evening object but quickly darts into the Sun’s glow, reappearing in the predawn sky for a spectacular encounter with Venus October 29 through November 4. By mid-November, Mercury disappears into the glow of sunrise, reappearing in the evening sky at the end of December. The Moon, Venus, and Mercury form a predawn riplet low in the east on November 13 and 14.

Venus sparkles brilliantly in the predawn sky in October, dropping slowly into the glow of the rising Sun. In December, it’s too close to the Sun to be observed. The Moon sweeps close on the mornings of October 14 and 15 and November 13 and 14. Between those lunar encounters, elusive Mercury makes a spectacular leap from the eastern horizon to join Venus; they form a beautiful morning duo from the last full week in October until mid-November.

Mars is due south at sunset, moving slowly from Sagittarius through Capricornus into Aquarius. The Moon swings by on the evenings of October 23, November 21, and December 20. On November 26, Mars is less than a degree from Uranus, serving as an easy guide about a week before and after November 26. Look nearby for a faint, greenish “star.”

Jupiter In October, Jupiter rises about midnight against Gemini, and is high in the south at dawn. By mid-November, it rises near 9 p.m., and by mid-December, it rises shortly after sunset to be visible for most of the night. The Moon swings by on October 9th and 10th, November 5th, and December 2nd.

Saturn Against Taurus, Saturn makes a slow east-to-west pass near the star Aldebaran. It rises near 10 p.m. in October, around 7 p.m. in November, and around sunset in December, with opposition on December 3. The Moon passes by on October 6 and 7, November 3 and 4, and December 1 and 27. The December 27 pass will be an occultation, with the Moon blocking Saturn from view in much of the United States.

  Sunrise Local Noon Sunset
October 1 7:05 a.m. pdt 12:59 p.m. pdt 6:52 p.m. pdt 
November 1 6:35 a.m. pst 11:53 a.m. pst 5:11 p.m. pst
December 1 7:07 a.m. pst 11:59 a.m. pst 4:51 p.m. pst
January 1 7:25 a.m. pst 12:14 p.m. pst 5:02 p.m. pst

(Times are for San Francisco, CA, and will vary slightly for other locations.)

"Shooting Stars"

November’s Leonid meteor shower offers the possibility of a spectacular display called a “meteor storm,” defined as more than 1,000 meteors per hour. That averages out to about one meteor every four seconds. Also known as “shooting stars,” meteors are particles of dust burning from the friction of high-speed entry into Earth’s atmosphere. Meteor showers occur when Earth passes through the dust left behind by a comet. The Leonids are caused by Comet Tempel–Tuttle dust laid out in a complex filament pattern. Earth will pass through three Leonid filaments this year. The most intense display is expected over eastern Asia, Australia, and the western Pacific Ocean, but the other two are expected to occur close together over North America between 1 a.m. and 4 a.m. on the morning of November 18. Weather permitting, observers in the United States who stay up late and get away from city lights have a chance to see an unforgettable display of nature’s fireworks.



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