SKY REPORTER: March 2012
by Steve Beyer on
Thursday March first, sunrise is at 6:29 a.m. Eastern Standard Time. That evening the sun, located in the constellation Aquarius, sets at 5:48 p.m.
Civil twilight occurs when the sun is less than six degrees of arc below the horizon. It precedes sunrise and follows sunset by about a half hour. During darker segments of this period the moon, bright planets, and several of the brightest stars might be seen.
Thursday March 15th sunrise is at 7:07 a.m. (Eastern Daylight Time) and sunset occurs that day at 7:03 p.m.
On the last day of the month, Saturday March 31st, the sun is in Pisces, rising at 6:40 a.m. and setting at 7:20 that evening. During March the length of time the sun is above the horizon each day increases by one hour 21 minutes. The altitude of the sun at noon, its maximum daily elevation, ascends during March from 42 degrees of arc on the first to 54 degrees on the 31st.
During this month average overnight temperatures recorded in Central Park rise from 29 degrees Fahrenheit on the first to 37 degrees on the last day of March.
Principal Phases of the Moon are:
|Full Moon||March 8|
|Last Quarter||March 14|
|New Moon||March 22|
|First Quarter||March 30|
During March, in addition to start of Daylight Saving Time and the beginning of the northern hemisphere’s spring season, there is a full slate of planetary activity. Venus, Jupiter, Mars, Saturn, plus elusive Mercury and faint Uranus are on the evening sky stage.
All month, brilliant Venus and Jupiter form a striking pair in the western sky for several hours after sunset. At the start of March they are easily seen in the same field of view after twilight fades.
During March, Mars is at its brightest for 2012. Early this month the red planet is at opposition, rising at sunset and remaining in the sky all night.
On March first, Mercury sets an hour and 28 minutes after the sun. The first weeks of this month provide opportunities for locating Mercury in the evening sky. Saturn rises at 9:33 p.m. on March first, other bright planets are all above the horizon at sunset.
Venus and Jupiter are spectacular visual treats throughout March. On the first of the month they are just 12 degrees of arc apart. They appear to approach each other until Tuesday the 13th, when the two are in conjunction. The brilliant planets then slowly separate, and by month’s end are 15 degrees apart in the western sky.
Mars is at opposition Saturday March third. It is then directly across the sky from the sun, and rises at about sunset. The red planet remains above the horizon all that night, shining at magnitude -1.2. Its distance from Earth then is about 62,658,700 miles, and the planet presents an apparent disk diameter of 14 seconds of arc. This small size makes viewing Martian surface details a challenging task, even with moderately sized telescopes. By comparison, during the great August 26, 2003 opposition, the disk of Mars appeared 21arcseconds in diameter.
Wednesday and Thursday, March 7 and 8 the moon appears near Mars in the constellation Leo.
On March 8 the Full “Worm” Moon is located in Virgo, 14 degrees southeast of Mars. Worms apparently become active this month. Other traditional names for March’s full moon include Full Crow Moon and Full Crust Moon, associations with late winter appearances of these loud birds and ice crusts on partially melted, then refrozen snow.
Saturday March 10th, the waning gibbous moon forms a nearly equilateral triangle with Saturn and first magnitude star Spica in Virgo. These objects are then seven degrees of arc from each other. The span is approximately equal to the apparent width of three fingers seen at arm’s length.
Daylight Saving Time begins during the early morning of Sunday March 11th when at 2 a.m. we set our clocks forward one hour.
Venus and Jupiter are in conjunction Tuesday March 13, with a separation of three degrees of arc, about six times the apparent diameter of the full moon’s disk.
On the night of March 14, the last quarter moon may be seen near the first magnitude red supergiant star Antares in the constellation Scorpius.
The northern hemisphere’s spring season begins at 1:14 a.m. EDT Tuesday March 20th when the sun is directly over a point on the equator at longitude103° 05' east, in Sumatra Indonesia, about 104 miles south-southwest of Singapore.
During early evenings of Sunday, Monday, and Tuesday March 25th through 27th, the waxing crescent moon is near Venus and Jupiter in the western sky. Such configurations are among the most spectacular and beautiful celestial sights to unaided eyes. Treat yourself to the breathtaking experience of seeing these configurations. Add to the pleasure by asking friends to sky watch with you.
On the night of the 26th, the moon is just three degrees of arc from Venus, and seven degrees from the Pleiades open star cluster. Sharp eyed observers may be able to discern six or seven stars in this famous cluster, including its brightest member, third magnitude Alcyone. The cluster’s brightest stars form a pattern that resembles a tiny dipper, considerably smaller than the Little Dipper in Ursa Major.
The First Quarter moon is in the constellation Gemini during the night of March 30th. It is among stars marking feet of mythical celestial twins Castor and Pollux.
During the early morning of March 31st Mars sets at 5:39 a.m. and Mercury rises at 5:58. That evening Saturn rises at 8:26 p.m., Jupiter sets at 9:57, and Venus disappears beneath the west-northwest horizon at 11:24.
March is the time of year when we prepare to bid temporary farewell to stars in and around Orion. By month’s end the sun’s progression through the zodiac begins to overwhelm light of stars typical of winter evenings. As springtime advances we say good-by to objects such as the Pleiades and Belt stars of Orion, and must wait until early mornings of August to revisit them.
Before that happens, we might turn a telescope to features such as the Great Nebula in Orion, located just south of the Hunter’s Belt, and resembling a “fuzzy star” to unaided eyes. And perhaps we might turn our telescope to the second magnitude star Castor, marking the head of the more northerly of Gemini’s twin stars. Nearby Pollux is the other star-brother-hero of ancient Hellenic mythology. Although seen as a single object to our unaided eyes, Castor is actually a multiple system containing three mutually orbiting sets of double stars, a total of six, whose blended light forms naked eye Castor. A small telescope reveals the three major components, designated Castor A, B, and C. The double nature of each is only revealed with the help of spectroscopic analysis.
Castor was said to have been mortal, while his brother Pollux was the immortal child of Leda and Zeus. Both were Argonauts who sailed in quest of the Golden Fleece and were considered patrons of navigators and warriors.