The Skywatcher's Diary for November 2005 has been prepared by Robert C. Victor, Staff Astronomer (retired). Credit to the author and to Abrams Planetarium, Department of Physics and Astronomy at Michigan State University, and mention of our Sky Calendar, would be appreciated.
A sample issue of the Sky Calendar is available over the Internet. It can be viewed via the World-Wide Web at http://www.pa.msu.edu/abrams/SkyCalendar/Index.html
If you would like a printed sample of the November issue, please send a long, self-addressed stamped envelope to:
November Sky Calendar
Abrams Planetarium
Michigan State University
East Lansing, MI 48824
Each month, the Department of Physics and Astronomy at Michigan State University makes the Skywatcher's Diary available over the Internet. It can be accessed at http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html
Current and back-issues of the Skywatcher's Diary are available in our archives at
http://www.pa.msu.edu/abrams/SkyWatchersDiary/Archives.html
This month, the unusual brilliance of Earth's two nearest planetary neighbors will attract the attention of even casual skywatchers. Mars reaches peak brilliance in early November, a few days after closest approach to Earth, and Venus will peak in early December. If you want to catch both planets at once, look near the times they're at equal altitudes above the horizon: Around an hour after sunset on November 5-6, or 45 minutes after sundown on November 15-16, and 20 minutes after sunset on November 26-27, over Thanksgiving weekend. Opportunities for children to view the planets can be arranged if school administrators or teachers arrange for a parent or a member of a local astronomy club to set up for viewing in a school yard. Even in the daytime, at the conclusion of the school day, Venus through a telescope reveals its changing phases, discovered by Galileo nearly 400 years ago! The planet will appear half full at the start of November, and one-third full at month's end. December will be even better for Venus, as it draws closer to Earth and shows an ever larger but thinner crescent, discernable even in binoculars. Venus will be visible in late afternoon and early evening until early January, from places where mountains don't block the view. Mars remains an evening object until August 2006, but it will fade sharply in coming months as Earth pulls away.
Following is a day-by-day guide to celestial happenings during November. For drawings of many of these events, and an evening sky map, request a free sample copy of the Abrams Planetarium Sky Calendar by sending a self-addressed, stamped envelope to Sample Sky Calendar, Abrams Planetarium, Michigan State University, East Lansing, MI 48823. Or you can subscribe for $11 per year.
Thirty minutes after sunset, although the sky is still quite bright, Venus should be plainly visible 15 degrees up in SSW to SW. If you have a unobstructed vantage point with no high mountains in that direction, look for a thin crescent Moon very low in SW, 23 degrees lower right of Venus. Binoculars show Mercury in same field 2 degrees to upper right of the Moon's northern cusp (upper point of the crescent). Don't worry if you miss Mercury! Much better chances to see it will come during evenings in February and June 2006. This evening, both Mercury and Venus reach "greatest elongation," respectively 24 and 47 degrees from the Sun. Here these inner planets appear farthest from the Sun, and are "coming around the bend" of their orbits and heading straight toward Earth. In coming weeks both planets will pass between Earth and Sun -- Mercury on November 24 and Venus on Jan. 13. After those dates, each planet will emerge into the morning sky.
Forty minutes after sunset, the 3-day-old crescent Moon can be found 7 degrees up in SW, with bright Venus 10 degrees to its upper left.
At sunset, find the Moon in the SSW, 22 degrees up, and Venus 3 or 4 degrees to its upper right. Forty minutes later, the Moon and Venus to its right, still within 4 degrees, make a beautiful sight together in binoculars, 18 degrees above horizon. At same time, Mars is 7 degrees up in ENE to E. To catch Venus and Mars at equal altitudes, wait another 30 minutes, when both will be 14 degrees up.
An hour after sunset, find Moon in SSW with Venus 16 degrees to its lower right. Venus won't be this far south again until November 2013. Thereafter Venus will appear slightly farther S on the same date at 8-year intervals until November 6, 2125. Also tonight, Mars is at opposition. Seen from above the solar system, Sun-Earth-Mars lie in a straight line. As we on Earth look at Mars tonight, we are facing directly opposite the Sunday Mars is in the sky all night: Look low in ENE at dusk, high in south in middle of night, and low in WNW at dawn.
This alignment of Mars takes place about every 25 to 27 months. The next time it will happen will be on Christmas Eve 2007. At 15- to 17-year intervals, Mars comes especially close, as it did in late August 2003, when it was within 35 million miles of Earth. The next time Mars comes closer than this year's 43 million miles will be when we pass it in July 2018 and in October 2020.
After nightfall, look for the Pleiades star cluster 16 degrees lower left of Mars. Tomorrow morning, just before twilight begins, Mars is low in the west with the Pleiades 16 degrees above.
This evening, the Moon is at First Quarter phase, so named because the Moon has traveled 90 degrees or one-quarter of the way around the sky since its passage by the Sun (New Moon) on November 1. Note the Moon's shape tonight is half full. Can you tell where the Sun is by looking at the Moon? As the sky darkens, note the 3rd-mag. star Deneb Algiedi, the Goat's tail, 7 degrees to Moon's upper left, and the first-magnitude star Fomalhaut, "Mouth of the Southern Fish," 23 degrees to Moon's lower left. At this time of year, Earth's orbital motion is carrying us away from the Goat's hindquarters. In three months, the Sun will cover up the same section of sky where the Moon appears half full tonight.
One hour after sunset, let Venus help you find the "Teapot," eight of the brightest stars of the constellation Sagittarius, the Archer. Binoculars may help you pick them out more easily. Just 1.6 degrees upper right of Venus this evening is the star Lambda Sagittarii, the top of the Teapot's lid. About 4 to 9 degrees upper left of Venus is a trapezoid of four stars forming the Teapot's handle. All four should easily fit within the field of 7-power binoculars. Its brightest member is Sigma in Sagittarius, or Nunki, a Euphratean name signifying "Star of the Proclamation of the Sea," referring to the section of the sky occupied by Capricornus, Aquarius, Pisces, and Cetus. As Venus shifts its position by nearly one degree per day toward the "Sea," it will appear 0.3 degree south (lower left) of Phi, lower right corner of the trapezoid, on Sunday November 13, then 0.5 degree W (lower right) of Nunki on Thursday November 17, and 0.4 degree E (upper left) of Nunki on Friday November 18.
The Teapot's stars appear lower each evening, owing to the Earth's orbital revolution around the Sun. The stars set 4 minutes earlier each day, and in late December and early January are hidden on the far side of the Sun. To find the Spout of the Teapot on November 11 from a place where mountains don't block the view, look for a triangle of stars 3 to 8 degrees below Venus.
If you have a clear and unobstructed view toward a distant horizon between E and ENE, you can see Mars in the daytime. Fifteen minutes before sunset today, locate the nearly full Moon 15 degrees N of E and just 7 degrees above the horizon. Look for Mars just over 2 degrees below the Moon and slightly left. It should be easy for binoculars, which may reveal Mars' tiny disk only one percent the apparent size of the Moon. (A 100-power telescope would make Mars look as big as the Moon appears to unaided eye.) You can track the Moon's motion against the background by checking every half hour through the evening. About 5 hours after sunset, the Moon and Mars will appear closest, with the Moon's southern edge passing just 1.7 degrees upper left of Mars. The Red Planet is still only 3 degrees from the Moon's edge 2 hours before sunup on Tuesday morning, when they'll be 13-16 degrees up in the west.
The Moon turns Full at 7:57 p.m. EST. About 15 minutes before sunset, persons with unobstructed views toward WSW and ENE would see both Sun and Moon one degree above opposite horizons. Notice Mars within 11 degrees to Moon's upper right, and Venus 47 degrees to Sun's upper left. After 3 hours pass, using binoculars, notice the Pleiades star cluster within 5 degrees to Moon's lower left. Shortly before sunrise on Wednesday morning, Moon will be passing very closely S of the Pleiades. As it orbits Earth, our Moon appears to pass this cluster about every 27.3 days. Several times next year, the Moon will actually cover some of its stars.
After nightfall look 9 degrees to Moon's lower right for the bright star Aldebaran, eye of Taurus. The Arabic meaning of this star name is "Follower" (of the Pleiades). An hour before sunrise on Thursday, the star is still 10 degrees to the Moon's south, now lower left. These years, this part of the Moon's orbit is tipped so the Moon passes widely north of the star, but during some other years of the 18.6-year cycle of the wobble of the Moon's orbit, the Moon can actually cover the star. But in those years the Moon will pass widely south of the Pleiades!
About 45 minutes after sunset, Venus in Sagittarius in SW and Mars in Aries in E are equidistant above their horizons. This evening the two planets appear 120 degrees apart in the sky, or one-third of the way around the zodiac. For proponents of astrology this arrangement, called a "trine," is considered a "favorable aspect." As the sky darkens, look for a 2nd-mag. star 0.5 degree upper left of Venus tonight and 0.4 degree lower right of the planet tomorrow night. The star is Nunki in Sagittarius, and one might inquire why astrologers list Venus' position tonight as 12 degrees in the sign of Capricorn!
Two hours after sunset, using binoculars, look about 2 degrees left of the Moon to see the 2nd-mag. star Beta Tauri marking the tip of the Bull's northern horn. Its Arabic name, El Nath, means "the Butting One." Moon and star will appear closest around 4 hours later, when star will appear 2/3 of a degree from Moon's northern edge. (Interestingly, astrologers give the Moon's position then not in Taurus, but as 23 degrees into Gemini.) For the next couple of years, the Moon will pass unusually close to this star until Luna's orbit tips southward again.
Tonight's northernmost Moon rises 2 hours after sunset some 35 degrees north of east. The Moon reaches its high point around 2:30 a.m. local time on Saturday, and then it sets far north of west before 11 a.m. on Saturday
At 11:00 p.m. on Friday, you can find Saturn, in Cancer, low in ENE about 20 degrees below the Gemini Twins, Pollux and Castor. At the same time, Mars is very high in SSW, 10 degrees lower left of 2nd-mag. Alpha in Aries. The Arabic name of this star is Hamal, the Full-grown Lamb. At 4 a.m. on Saturday, you'll find Mars low in W and Saturn high in SE. Between those times, the planets stay 90 degrees apart, or one-quarter of the way around the zodiac. This arrangement is called a square or quadrature by astrologers, which they consider unfavorable. Mars appears in Aries and Saturn in Cancer, although astrologers list their current positions in Taurus and Leo, which are also a quarter of the way around the zodiac, but one constellation farther to the east. The reason: The starting point of the astrologers' zodiac is the moving Vernal Equinox (Sun's place on the first day of spring), which as the Earth's axis wobbles or precesses like a top, moves completely around the zodiac in 25,800 years; thus in 2000 years this starting point has move backward from Aries back into Pisces. But astrologers still name their signs beginning with Aries, even though the Sun now spends most of the first month of spring in Pisces, the previous constellation.
For the rest of the month, the Moon will pass several bright objects in the morning sky. These will be listed on the evening before, so you can plan to set your alarm to wake up early. All times are local for mid northern latitudes.
Around 10:30 p.m. look in ENE for Moon with the Gemini Twins Castor, 6 degrees to Moon's left, and brighter Pollux the same distance to Moon's lower left. Saturn is 19 degrees below Pollux but only 6 degrees above the horizon. At 5:00 a.m. on Sunday, Moon is high in WSW to W, with Pollux just over 3 degrees above the Moon, Castor 5 degrees to Pollux's right, and Saturn 22 degrees to Moon's upper left.
At 10:30 p.m., the Gemini Twins Pollux and Castor are 7 and 11 degrees above the Moon, while Saturn is 12 degrees below, all in ENE. By 5 a.m. on Monday, Moon is very high in SW, with Saturn 10 degrees to Moon's upper left, and the Twins 9 to 13 degrees to Moon's lower right.
At 10:30 p.m., look for the waning gibbous Moon low in ENE with Saturn 4 degrees to its right. Around this date each year, as we look at the Pleiades star cluster, we are facing outward in our solar system, directly away from the Sun. The Pleiades cluster is low in ENE at nightfall, passes about 15 degrees S of overhead for latitude 40 degrees north just before 11:30 p.m., and is low in WNW at first light of dawn. At 5 a.m. on Tuesday, the Moon is high in S with Saturn 5 degrees lower right, while Regulus, heart of Leo the Lion, lies 16 degrees to Moon's lower left. Annually at this time of year, the Earth's orbital revolution around the Sun is carrying us toward Regulus in the morning sky. More tomorrow.
On Wednesday morning at 5 a.m., the Moon is very high in SSE and just over half full. The star Regulus, heart of Leo, is just 4 degrees below the Moon, while Saturn is 16 degrees to Moon's upper right. Bright Jupiter is low in ESE, with Spica 13 degrees to its upper right. As the Earth heads toward Regulus and traces out its curved orbit around the Sun, we have already overtaken Mars (which is below the WNW horizon) just over two weeks ago, and we will swing between Saturn and Sun in late January, and eventually between Jupiter and Sun in early May. On those dates each planet will move to the western sky at dawn, at opposition to the Sunday They'll also be seen in the eastern sky at dusk, and high in the south in the middle of the night, so they'll be up all night!
Around 11:30 p.m. the Moon, just past Last Quarter phase and slightly less than half full, rises approximately 15 degrees north of east. Note the star Regulus 7 degrees to Moon's upper right. At 5 a.m. on Thursday, Moon is high in SE, with Regulus 9 degrees upper right, and Saturn 19 degrees upper right of Regulus.
Today Mercury passes nearly between Earth and Sun, although it misses passing directly in front of the Sun's disk. (Such an event, called a transit, will happen next year on November 8.) Today's alignment of Sun-Mercury-Earth is called an inferior conjunction of Mercury. In about a week, Mercury will start to appear low in ESE morning twilight, dimly at first, but then it will brighten rapidly in early December for an excellent morning apparition. At 5 a.m. on Friday November 25, locate the fat crescent Moon in SE with Denebola, tail of Leo, 11 degrees to its upper left.
Now that the Moon is a thinning crescent in the morning sky, only about one-fourth full in Saturday's predawn, it is time to take out your binoculars and enjoy the starfield around Saturn. At 5 a.m. these mornings, Saturn is very high in SSW. In the same binocular field 4 degrees to Saturn's right, you will notice a sprinkling of stars called the Beehive cluster. Saturn has already passed this cluster once, and now begins to appear to move retrograde or backwards (because the Earth is starting to overtake it). Saturn will appear to back up past the southern fringes of the cluster in early February (visible nearly all night), and then go forward past the cluster in early June, in the evening sky.
The two brightest objects visible at 5:30 p.m., Venus in SW and Mars in E, are 110 degrees apart tonight. Twelve hours later, at 5:30 a.m. on Sunday, the two brightest "stars" visible are Jupiter, low in ESE, some 20 degrees lower left of the crescent Moon, and Sirius, the "Dog Star," about 20 degrees up in SW. Notice how Sirius twinkles much more than Jupiter does. Other bright objects, ranking in a near tie for 3rd place, are Arcturus approximately 30 degrees up in E, Capella around 40 degrees up in NW, Saturn near 65 degrees up in SW, Procyon 45 degrees up in SW to WSW, and, except for atmospheric effects caused by its low altitude, Rigel 9 degrees up in WSW. Look for the first-magnitude star Spica in Virgo, 9 degrees below the Moon and 13 degrees upper right of Jupiter.
On Monday at 5:30 a.m., look between ESE and SE for the thin crescent Moon with Jupiter 8 degrees lower left and Spica 5 degrees upper right. This is a good morning to look for "Earthshine," the dark side of the Moon illuminated only by the sunlight reflected off the Earth onto the Moon. Binoculars give an especially striking view.
On Tuesday morning, November 29 an hour before sunrise, look for the last very easy old crescent Moon 10 degrees up in ESE with bright Jupiter 6 degrees upper left, and the 3rd- mag. star Alpha in Libra 5 degrees lower left. Another 3rd-mag. star in Libra, Beta, is 9 degrees left of Alpha. The names of these two stars, Zubenelgenubi and Zubeneschamali, refer to their positions marking the tips of the southern and northern claws of an older version of the Scorpion.
You may have another chance to see the old Moon, on Wednesday morning: Forty minutes before sunup, find Jupiter 19 degrees up, between ESE and SE. Using binoculars, try for faint Mercury 19 degrees to its lower left. (Aim binoculars 16 degrees below Jupiter, then move 9 degrees left.) If you spot Mercury, look about 6 or 7 degrees to its lower right for a very thin crescent Moon, just 25 hours before New. You need very clear skies and an unobstructed view, because at that time the Moon is less than 2 degrees up.
One-and-a-half hours after sunset, the eight brightest objects in the sky are, in order of brightness: Venus, 12 degrees up in SW; Mars, 36 degrees up in E; Vega 43 degrees up in WNW; Capella 23 degrees up in NE; Altair 40 degrees up in WSW; Aldebaran 13 degrees up in ENE to E; Fomalhaut 20 degrees up in S; and Deneb, 67 degrees up in WNW.
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Please send any comments, suggestions, or questions to Thomas G. Ferguson: fergus52@msu.edu |