A reader emailed to inquire about cross-quarter days as mentioned in the February Maine Skies. The year is divided up into two solstices and two equinoxes. The winter solstice, Dec. 21 in 2012, is when the sun is at its farthest point south of the equator, while the summer solstice, June 20, is when it is at its northernmost point. The spring, or vernal equinox, the point at which the sun crosses the equator into the northern hemisphere, is March 20, while the reverse crossing, the fall or autumnal equinox, will take place on Sept. 22. The halfway point between a solstice and equinox is called a cross-quarter day. These are Candlemas or Groundhog Day on Feb. 2, Beltane or May Day on May 1, Lammas on August 1, and All Souls’ Day or Halloween on Oct. 31. The cross-quarter days held great significance to pagan religions and the very early Christian church.
Focus on the planets
Fred Schaaf in Sky & Telescope magazine reports that six of the brightest objects in the sky are visible in the night sky about 45 minutes after sunset. These are the moon, Mercury, Venus, Jupiter, Mars and Sirius.
Mercury lies low in the west at sunset and offers the best opportunity to view the innermost planet this year. Start early, for Mercury will fade quickly and disappear from view by mid-March.
Venus is high in the west at sunset and is the brightest object in the sky other than the moon. On March 26 it is reported that Venus will reach its highest point in the sky for its entire 8-year cycle.
Mars shines brightly in the east about an hour after sunset. On March 7, the Red Planet lies just to the upper left of the moon.
Jupiter makes up the other half of the duo, along with Venus, in the west after sunset. Watch as the two move together for a spectacular conjunction on March 15. Features such as the Jovian belts and the four moons will be on display.
Saturn rises in the southeast about midnight and is up for the remainder of the night. The rings are still open although narrowing from last month and its major moon, Titan, is on display as it makes two orbits about the planet in March.
Uranus is to the upper left of Mercury as March opens but will very difficult to spot as it is setting almost as the sun comes up. Neptune is totally lost in the sun’s glare this month.
1: Sunrise, 6:14 a.m.; sunset, 5:22 p.m. Moon in first quarter, 8:22 p.m.
7: Look for Mars to the upper left of the nearly full moon tonight.
8: Full moon, 4:41 a.m. The full moon of March is called variously the Worm Moon, Crow Moon, Sap Moon or Lenten Moon.
10: The moon is at perigee, or nearest approach to Earth, today. The combination of perigee and a nearly full moon can lead to abnormally high tides.
11: This is the second Sunday in March and time to change your clocks ahead by one hour as the nation shifts to Daylight Saving Time. The sun enters Pisces on the ecliptic.
12: Look for Jupiter and Venus side by side in the western sky an hour after sunset. Watch the two planets come together for a close conjunction on March 15.
15: The Ides of March. A bad day for Julius Caesar. Moon in last quarter, 9:26 p.m.
17: St. Patrick’s Day. Tradition has it that this is the time to plant your peas.
20: Spring or vernal equinox, 1:13 a.m. This is the point where the sun crosses the equator into the northern hemisphere. The sun enters the astrological sign of Aries at the equinox, although astronomically it is still in Pisces.
22: New moon, 10:38 a.m.
25: A thin crescent moon is just to the upper right of Jupiter on the western horizon after dark. Venus blazes just above.
26: The moon is at apogee, or farthest distance from Earth, today.
30: Moon in first quarter, 3:41 p.m.
31: Sunrise, 6:19 a.m.; sunset, 7:01 p.m.
Send astronomical queries to Clair Wood at firstname.lastname@example.org or care of the Bangor Daily News, Style Desk, P.O. Box 1329, Bangor 04402.