| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Skyguide January - March 2002 January 3: The Quadrantid meteor shower is active January 1-5, with a brief peak averaging about 40 meteors per hour on the morning of the 3rd. The brightness of the waning gibbous Moon may interfere with viewing. However, you can tune an FM radio to a distant transmitter and listen to short bursts of noise fading in and out as the meteors cause changes in the atmosphere that reflect radio signals. January 13: New Moon. Not visible tonight. In two days, use binoculars to look low in the southwest soon after sunset for greenish Uranus, about 5 degrees north of the crescent Moon. January 28: Full Moon, known as the “Wolf Moon” to the Algonquin, “Cold Weather Moon” to the Nez Perce, and “Younger Moon” to the Haida. February 11: New Moon just before midnight. Chinese year 4700, Year of the Horse, begins tomorrow. February 27: Full Moon, known as the “Black Bear Moon” to the Kutenai. Tonight the Moon appears because we’re observing it from the same direction that sunlight is coming from and there are no shadows on its surface. The most dramatic time to observe the Moon’s surface relief is around first quarter, when long shadows make craters and mountains stand out. March 13: New Moon. Sighting the very thin crescent Moon at sunset was an important moment for cultures that relied on a lunar calendar. Tomorrow night, the crescent marks the start of the Muslim New Year 1423. Look for the bright planet Venus above and slightly to the right of the Moon. March 20: Spring Equinox in the Northern Hemisphere. Spring officially begins at 11:17a.m. pst—the Sun rises due east and sets due west on this day. As the Sun’s arc continues moving slowly northward, daylight hours increase. Mercury: Elusive Mercury starts the year off reaching greatest eastern elongation (its greatest angular separation from the Sun) around January 11. It is visible low in the west after sunset. The planet darts back into the Sun’s glare by month’s end and disappears until early February, when it rises in the east just before the morning Sun. Its greatest western elongation occurs on February 21, and it continues to hang in the morning sky through the end of March. However, it’s a challenge to find. Look for the crescent Moon, which will be near the planet on the evening of January 14. The Moon and Mercury rise together on the morning of February 9 about an hour before dawn and March 11 about a half hour before dawn. Venus: On January 14, Venus is on the other side of the Sun from Earth and washed from view by the Sun’s glare. It starts climbing out of the twilight near the end of March and is visible in the west after sunset. The crescent Moon appears very near the Sun on the evening of February 12 (setting only 30 minutes after sunset), slightly below Venus on March 14, and slightly above Venus on the 15th. Mars: In January, the Red Planet is high in the south-southwest at sunset, setting about five hours later. As the season pro- pro-gresses, Mars slowly moves westward, gradually setting earlier each night. At the same time, its distance from Earth will increase as our planet pulls ahead of slower- moving Mars in their orbital race around the Sun. This will cause Mars to gradually grow fainter in the sky. The Moon sweeps nearby on the evenings of January 18, February 16, and March 17. Jupiter: In January, the largest planet in our solar system rises at sunset against the stars of Gemini and is visible all night long as it slowly moves from east to west. This is a good time to observe the giant planet through small telescopes, which will easily reveal its disk and four largest moons. Jupiter rises about four minutes earlier from day to day, appearing higher at sunset from one night to the next. By the end of March, it’s high in the south at sunset. The Moon swings by very close on February 22—two hours before sunset, try to spot the Moon and Jupiter about half a degree apart in the sky. Saturn: The Ringed Planet is the slowest moving of the naked-eye planets, lingering against the stars of Taurus all season and never moving far from the bright, red star Aldebaran. January finds it high in the east at sunset, even better- positioned for observing than Jupiter, since it’s above the haze and atmospheric distortion that hinder the view of objects close to the horizon. Small telescopes can resolve its bright rings and at least one of its moons. Earth’s Moon is juxtaposed with Saturn on the evenings of January 23 and 24, February 20, and March 19.
(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 |