To the reader:
The Skywatcher's Diary for November 2004 has been prepared by
David Batch. 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
ftp://www.pa.msu.edu/pub/swd/
Skywatcher's Diary: November 2004
The two bright beauties Venus and Jupiter attract attention in the east before
dawn. Tomorrow morning they stand 3 degrees (2 finger widths) apart. Venus is
the brighter and higher of the duo. Sixteen degrees (1 1/2 fist widths) below
Jupiter rests another celestial pair: Mars and the star Spica. Fainter Mars is
passing the star on the left. Their separation is similar to the Venus-Jupiter span.
Today, properly set sundials and clocks are out of sync by the maximum amount
possible ‹ just over 16 minutes. The two timepieces disagree because they
employ different references. The sundial uses the sun, of course, but Sol's
motion across the sky is variable, providing days that have slightly different
lengths over the course of the year. Clocks are designed to average out the
variations and give precise, even timekeeping.
Over the next two mornings Venus and Jupiter reach their minimum separation.
Tomorrow before dawn they stand 0.8 degree (1 1/2 moon widths) apart, with
Venus above and slightly left. The following morning the split is 0.7 degree and
Venus is to the left. Continue watching the planets as they drift apart. Venus visits
Mars next, in early December. Then the separation between planets is a little
more than a degree.
The Moon reaches Last Quarter at 53 minutes after midnight tonight, Eastern
Standard Time. Technically, the date is November 5. Luna is low in the eastern
sky at that time, having risen scarcely more than an hour earlier. By an hour
before sunrise, the Moon has climbed high in the southeast, near the head of
Leo, the Lion. Leo's heart, marked by the star Regulus, lies 14 degrees (1 1/2
fists) to the Moon's lower left.
Have you noticed the sunset position recently? Sol's been making steady
progress toward the south, now setting nearly west-southwest. The sun has
another 10 degrees to go to reach it's farthest point south, but it will take more
than a month and a half to get there. When will the sun again be setting at
tonight's spot? February 4 is the answer.
The Milky Way Galaxy is nicely placed for evening observing, passing overhead
near the end of dusk. The Moon doesn't rise until after midnight, local time, so
you've got more than 5 hours of dark sky -- enough to be worthy of an observing
expedition to a rural area. The Great Rift is sitting high in the southwest, running
from Deneb, in Cygnus, down through the Summer Triangle. That rivulet of
obscuring matter seems to split the Milky Way into two streams.
Saturn rises about 5 hours after sunset. It follows the Gemini Twins, Pollux and
Castor, over the east-northeastern horizon. Tomorrow morning, the planet
reaches its farthest point eastward within the constellation of Gemini. Thereafter it
begins retrograde, or starts sliding westward relative to the starry background.
The motion is subtle. To detect the movement, you will need to carefully note
Saturn's position within Gemini over a period of weeks.
Celestial scenery alert. Tomorrow morning the ever-photogenic crescent Moon
perches 2 degrees (4 moon diameters) above giant Jupiter. Sister Venus sits 4
degrees below and left of big brother. The following morning Luna drops below
both planets. Next month when the Moon visits Jupiter, it completely occults, or
covers, the planet for about an hour.
The faintest stretch of the zodiac now lies before us in the southern sky after
evening twilight. It includes (from southwest to east) Capricornus, Aquarius,
Pisces, and Aries. The brightest star in the group is 2nd-magnitude Hamal, or
Alpha in Aries, about 30 degrees (3 fists) up in the east 1 1/2 hours after sunset.
You will need a clear, dark sky and a good star map to appreciate this region.
Tomorrow morning is your last chance to catch a glimpse of the waning crescent
Moon. Look low on the east-southeast horizon 45 minutes before sunrise. Faint
Mars perches 5 degrees (half a fist) above Luna. The star Spica lies another 7
degrees to the upper right of Mars, and Venus and Jupiter sit above Spica 8 and
14 degrees, respectively.
Capella is the brightest star low in the northeast as dusk descends. A line drawn
between Capella and Polaris, the North Star, passes through a rather empty
patch of sky that goes by the tongue-twisting designation of Camelopardalis, the
Giraffe. The constellation is a relatively new invention, created in 1614. The name
literally means "camel leopard."
Astronomical New Moon occurs at 9:27 a.m. EST. This phase is never discernible
unless it creates a solar eclipse, and then only in silhouette. Nevertheless, New
Moon is of primary importance because it marks the beginning of each lunar
cycle, or lunation. Since the New Moon is not visible, some early societies used
the term to mean the first thin crescent to appear after sunset.
For "young moon" aficionados, the crescent presents a worthy challenge tonight.
Although the Moon is relatively old, approximately 32 hours past New, it's orbit
hugs the horizon this time of year for mid-northern locales. The Moon sets about
30 minutes after sunset, so look before then. Luna lies between southwest and
west-southwest, 3 degrees to the lower right of Mercury and half a degree to the
upper right of Antares. Because the Moon's orbit tilts more upright the farther
south you go, southern observers have the advantage.
The thin crescent is easier tonight. Look for it 5 degrees (half a fist) above the
southwest horizon 45 minutes after sunset. Mercury is 11 degrees to the lower
right of Luna. By tomorrow night the Moon climbs another 7 degrees higher and
12 degrees farther south. Then look for the stars of the Sagittarius "teapot"
surrounding the Moon as twilight fades.
Uranus and Neptune are well placed for evening observing. They straddle the
meridian (due south) at the end of evening twilight. Sixth-magnitude Uranus sits
among the stars of Aquarius, within a triangle created by Sigma, Theta, and Iota.
Neptune, two magnitudes fainter than its sibling, lies farther west. It's about 1
degree to the west of 4th-magnitude Theta in the constellation Capricornus.
For those who remember the excitement surrounding the Leonid meteor shower
a few years ago, you may wonder what happened to it. The Earth is not predicted
to pass through dense regions of the comet debris that produced the dazzling
meteor storms of recent memory for a couple more decades. If you'd like to
witness the current version of the Leonid shower, look tomorrow morning before
dawn. Expect no more than one meteor every 4 minutes, on average.
Have you noticed the bright star low on the southern horizon at the end of evening
twilight? It's 1st-magnitude Fomalhaut (FOE mal awt) located in the obscure
constellation of Piscis Austrinus, the Southern Fish. The star reaches due south
close to 3 hours after sunset. It attains a maximum altitude for mid northern
latitudes of only 20 degrees (2 fists), so the star is easy to miss unless you have
a clear southern vista.
The star Fomalhaut can be located by following the right (west) side of the Great
Square of Pegasus down toward the southern horizon. Fomalhaut is a few
thousand degrees hotter than our sun and about 16 times more luminous. An
enormous disk of dust particles has been discovered around the star, perhaps
the beginning stages of a planetary system in formation.
First Quarter Moon occurred at 50 minutes past midnight this morning. Over the
last several mornings Venus has been drifting past Spica, the brightest star in
Virgo. This morning before sunup the star is 4 degrees (half a fist) to the right of
Venus. Tomorrow morning the planet slides slightly lower and the separation
increases by a degree. Jupiter perches 15 degrees to the upper right of Venus;
fainter Mars lies 9 degrees to the lower left.
Mercury reaches "greatest elongation" from the sun this evening, normally a good
time to observe the planet. This time of year, however, Mercury's orbit tilts more
horizontally, keeping the planet relatively low -- and difficult to see -- for mid-
northern latitudes. Try your luck about 45 minutes after sunset. The planet then
sits 2 degrees off the horizon and 6 degrees to the right of due southwest.
Magnificent Orion now sets close to sunrise, but it doesn't yet rise at sunset. The
paths of the sun and constellation across the sky are different. Orion rises due
east and sets due west year round, spending about 12 hours above the horizon
during each day-night cycle. The sun's path changes with the seasons. It currently
rises about 25 degrees to the south of east (mid-northern latitudes) and sets the
same amount south of west, providing only 9 1/2 hours of daylight.
Today the sun enters the astronomical constellation (not astrological sign) of
Scorpius, but it spends only a week within the boundaries of the constellation. It
next moves into Ophiuchus and stays there 18 days, until December 17. You say
Ophiuchus is unfamiliar to you? It represents a person holding a serpent,
symbolizing the universal struggle of good versus evil. The figure is also
associated with Aesculapius, the first physician.
Cetus, the Sea Monster or Whale, sprawls across the southeastern portion of the
evening sky. It lies beneath Pegasus and Andromeda and about a third of the way
up from the horizon. Cetus also shares mythology with those two constellations.
Andromeda is the damsel in distress whom Cetus is about to devour, until the
hero Perseus swoops down on Pegasus to save the day. The brightest star in
Cetus is 2nd-magnitude Diphda, located 20 degrees above southeast about 11/2
hours after sunset.
The bright star just above the east-northeastern horizon at nightfall is Aldebaran,
eye of Taurus, the Bull. Don't mistake it for Capella, even brighter and somewhat
higher and farther to the northeast. Both stars are part of the glorious
assemblage of brilliant wintertime stars associated with Orion. Soon that
constellation will be rising, "throwing a leg up over our fence of mountains," as
Robert Frost described the event in his poem The Star-Splitter.
The almost full Moon rises just shy of an hour before sunset, so a keen-eyed
observer can spot it a little before sundown in the east-northeast. After dark, look
for the Pleiades star cluster 6 degrees (half a fist or 12 moon diameters) to
Luna's left and slightly lower. To more easily detect the Pleiades, cover the Moon
with your hand. Watch Luna approach the cluster all night. Don't forget your
binoculars.
The Moon turns Full at 3:09 p.m. EST. In colonial times the full moon of November
was known as the Beaver Moon or Frosty Moon. Tonight you can glimpse the
Moon rising close to sunset. Once the sky turns dark, look for Aldebaran 8
degrees (almost a fist) below and slightly right of Luna. The Pleiades star cluster
appears 8 degrees to the Moon's upper right.
Saturn rises just under 4 hours after sunset. The Cassini spacecraft is currently
in orbit around Saturn, examining the planet, its famous rings, and the multitude
of Saturnian moons. Early next year the Huygens probe that piggybacked on
Cassini will attempt a landing on the planet's largest moon, Titan. For the latest
information, visit NASA's website http://saturn.jpl.nasa.gov/home.
Venus is closing in on Mars. Tomorrow morning before dawn they are 4 degrees
(half a fist) apart, with Mars to the lower left of Venus. The two planets are also
approaching Alpha in Libra, a 3rd-magnitude star 3 degrees to Mars' lower left.
Alpha has a fainter companion star only 1/20th degree above it. The planets and
Alpha appear closest together in early December.
For those skywatchers who take comfort in sighting the Big Dipper, this is a tough
time of year. The Dipper skims the northern horizon, so it's easily lost in city lights
or landscape obstacles. A worthy stand in for the Dipper is Cassiopeia, the "W"-
shaped pattern that now perches high in the northeast. The two constellations lie
on opposite sides of Polaris, the North Star. They can be thought of as a set --
when one's down, the other is up.
Tonight the Moon rises 3 hours after sunset, considerably north of east. Try to
catch the waning gibbous orb at least an hour after it rises, or about 9 o'clock
local time. Saturn sits 5 degrees (10 moon diameters) to the Moon's lower right.
The Gemini Twins, Pollux and Castor hang over Luna. Pollux is 3 degrees above
the Moon and Castor another 5 degrees above Pollux.
Please send any comments, suggestions, or questions to
Thomas G. Ferguson:
fergus52@msu.edu
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