Monster Media 1996 #14/Monster Media No. 14 (April 1996) (Monster Media, Inc.).ISO/math/sky_0196.zip/SKY-0196.TXT

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    Abrams Planetarium SKYWATCHER'S DIARY Jan 1996
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The Skywatcher's Diary for January 1996 has been prepared by Robert
C. Victor. Credit to Abrams Planetarium, Department of Physics and
Astronomy at Michigan State University would be appreciated. Our
illustrated Sky Calendar accompanies the printed version of
Skywatcher's Diary as it is sent monthly to Michigan newspapers, but
does not accompany this Internet version. If you would like a sample
copy, send your request with a self- addressed, stamped envelope to

Sky Calendar
Abrams Planetarium
Michigan State University
East Lansing, MI 48824

A sample Sky Calendar of a past month is available over the Internet. It
can be accessed via a World-Wide Web browser such at Netscape or
Mosiac, directly at URL:

http://www.pa.msu.edu/abrams/novskycal.html

The Department of Physics and Astronomy at Michigan State University
has now made the Skywatcher's Diary available over the Internet. It can
be accessed via a World-Wide Web browser such as Netscape or
Mosiac, directly at URL:

http://www.pa.msu.edu/abrams/diary.html

******Lunar and Planetary Highlights for January******
At dusk at the start of January, three planets are visible with unaided
eye: Brilliant Venus in the southwest, Saturn over 30 degrees to Venus'
upper left, and Mercury near the horizon to Venus' lower right. Mercury
sinks and fades in January's second week, while Venus and Saturn
approach each other all month, the gap between them closing by just
over one degree each day. Dawn watchers can see Jupiter emerge from
the Sun's glare on the ESE to SE horizon in January's 2nd week. Look
for a thin crescent Moon near Jupiter on Jan. 18, and an even thinner
crescent to Jupiter's lower left on the next morning. The first easy view
of an evening crescent occurs at dusk on Jan. 21, with the Moon
climbing near brilliant Venus on Jan. 22 and near Saturn on Jan. 23.
Venus and Saturn approach within 5 degrees apart by Jan. 28, and 2
degrees apart by Jan. 31. (They will appear closest to each other on
Feb. 1 and 2.) The Moon can be found very near the star Aldebaran at
dusk on Jan. 2 and again one true lunar orbital period (27.3 days) later
on the night of Jan. 29.

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**Astrophotography Project: The Conjunction of Venus and Saturn**
Using a 35-mm camera with a standard lens (about 50-mm focal
length), take nightly photographs of Venus and Saturn against
background stars. Use a tripod to steady the camera, and fast film such
as Ektachrome 400. On clear evenings Jan. 20-Feb. 14, one-and-a-half
hours after sunset, take a 15-second exposure with a wide-open fast
lens such as a 50-mm f/1.2 to 2.8. The field of view of a 35-mm camera
with a standard lens of 50-mm focal length is about 36 degrees by 24
degrees. For each photo, aim the camera to orient the long dimension of
the field vertically, with the horizon just within the lower edge of your
field. You'll obtain an impressive set of teaching slides showing the fast
eastward motion of Venus and slow eastward motion of Saturn against
background stars, the relative motion of Venus past Saturn, and the
seasonal drift of the starfield toward the western horizon.

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Monday, January 1
At nightfall, brilliant Venus is low in SW, while the Pleiades (Seven
Sisters) star cluster is high in the eastern sky 7 degrees to the Moon's
upper left. Follow Venus and the Pleiades for the first four months of
1996; in early April they'll pass very close to each other in the western
evening sky.

Tuesday, January 2
Mercury appears farthest from the Sun tonight. Forty-five minutes after
sunset, look for brilliant Venus in the SW, with Mercury 14 degrees to
its lower right. Using binoculars, can you see Mars within 6 degrees to
Mercury's lower right?

The first-magnitude star Aldebaran, eye of Taurus the Bull, appears
within a couple of degrees of the Moon at dusk. Look every hour as the
evening progresses, and watch them separate, owing to the orbital
motion of the Moon around the Earth.

Wednesday, January 3
Remember how close to each other Aldebaran and the Moon appeared
last night? This evening at dusk, the Moon has moved on, and appears
some 13 degrees to the east (lower left) of that star.

Thursday, January 4
Orion is magnificent, even when low in the sky in twilight and bright
moonlight. An hour after sundown, look for reddish Betelgeuse,
Orion's bright shoulder, 12 degrees right of the Moon tonight. The
Hunter's belt, a vertical line of three stars, appears 10 degrees right of
Betelgeuse. Rigel, Orion's foot, lies 9 degrees right of the belt. The
opening lines of Robert Frost's poem, "The Star-Splitter", has a good
description of Orion rising:

"You know Orion always comes up sideways.
Throwing a leg up over our fence of mountains,..."

Friday, January 5
Does the Moon seem unusually large when it rises in ENE shortly after
sunset this evening? Actually, it's only an illusion, since this Moon after
Yule happens to be the most distant Full Moon of 1996.

Saturday, January 6
The Moon rises tonight about 1-1/4 hours after sunset, the exact time
depending on your location. Another hour later, look in the east for
Procyon 11 degrees to the Moon's right. Another 26 degrees right of
Procyon [and a bit lower, from northern U.S.], look for twinkling
Sirius, the Dog Star and brightest star of the nighttime sky. You can
also locate Sirius by following Orion's belt down toward the ESE
horizon.

Sunday, January 7
At nightfall, locate Saturn in SW, 29 degrees upper left of Venus.
Before the Moon rises, while Saturn is still well up in a dark sky, view
Saturn through a good telescope. You'll see a dark band across the face
of the planet, which consists mostly of the dark face of Saturn's rings,
and partly the rings' shadow. But can you also see the darkened rings to
the sides of the planet? You have a good chance to detect them this
week. Although their shaded side is now tipped toward Earth, the rings
aren't *completely* dark, because they're not solid. Some sunlight
reflected from the rings' lighted side manages to make it through the
rings toward Earth.

Monday, January 8
Some 4-1/2 hours after sunset, face east to see Regulus, heart of Leo,
about 7 degrees lower left of the Moon. They keep company for the rest
of the night; at dawn on Tuesday, they're in the WSW, with Regulus
above the Moon.

Tuesday, January 9
Some 4-1/2 hours after sunset, the Moon has just risen in the east, with
Regulus 8 degrees above it.

Wednesday, January 10
Some 45 minutes after sunset, binoculars help locate Mercury 20
degrees lower right of Venus in SW. Mercury will sink and fade quickly
in the remainder of this week, but Saturn, 25 degrees upper left of
Venus tonight, remains in easy view. A week from today, Mercury
passes inferior conjunction, nearly between Earth and Sun. Around
such times Mercury is invisible, because it appears as a faint, thin
backlighted crescent only a few degrees from the Sun. Late this month,
Mercury will reappear in the ESE at dawn.

Thursday, January 11
Castor and Pollux, two bright stars just 4-1/2 degrees apart marking the
heads of the Gemini twins, are now visible all night: Low in ENE at
dusk, high in S in middle of night, and low in WNW at dawn. That's
because in the second week of January each year, as we face these stars,
we are looking outward, directly away from the Sun. Keep track of
these "Twin" stars an hour after sunset evenings until late June, and
watch how they appear to drift across the sky as the Earth revolves
around the Sun.

Friday, January 12
An hour before sunup on Saturday, the Moon is in SSW. Just over 90
degrees (1/4 circle) west of the Sun, the Moon is approaching Last
Quarter phase and is still slightly more than half full. Look for Spica
about 5 degrees to Moon's lower left.

Saturday, January 13
The Moon is in the south an hour before sunrise on Sunday. It has
passed Last Quarter phase and is visibly less than half full. Note Spica 8
degrees to the Moon's right.

Sunday, January 14
In mid-January each year, the Summer Triangle is visible both at dusk
and again at dawn. Altair, its lowest and southernmost star, is low in
west at dusk and low in east at dawn. Vega and Deneb are 34 and 38
degrees away from Altair and farther north. At dusk, Deneb marks the
top of the triangle. At dawn, Vega, the triangle's brightest star, marks
the top.

Monday, January 15
An hour before sunup on Tuesday, the waning crescent Moon is in SSE
with the three stars of the head of Scorpius just below. Reddish
twinkling Antares, heart of the Scorpion, is 12 degrees to Moon's lower
left. Can you see bright Jupiter just risen in ESE to SE, 24 degrees to
Antares' lower left?

Tuesday, January 16
An hour before sunup on Wednesday, the thin crescent Moon is in SE.
First-magnitude Antares, the Scorpion's heart,lies 9 degrees to the
Moon's lower right, while bright Jupiter has just risen 19 degrees to
Moon's lower left.

Wednesday, January 17
An hour before sunrise on Thursday, a very pretty crescent Moon is low
in SE with Jupiter about 5 degrees below. Jupiter rises about two hours
earlier with each passing month; around midyear Jupiter will rise at
sunset and be up all night, near the Full Moon on the night of June 30.

Thursday, January 18
Last chance to see the old Moon: About 45 minutes before sunup on
Friday morning, look low in SE for Jupiter, with a very slender Moon
12 degrees to its lower left. From mid-Michigan, it'll then be only about
24-1/2 hours before Saturday's New Moon. A Friday morning sighting
from the West Coast would be only about 22 hours before New. A
sighting from Hawaii would be about 20 hours before New. Binoculars
enhance the view of the very delicate crescent. Note the times you last
see the Moon with unaided eye and with optical aid.

Friday, January 19
The closest New Moon of the year occurs Saturday morning, at 7:50
a.m. Eastern Standard Time (4:50 a.m. Pacific Time, 2:20 a.m. Hawaii
Time). Seacoasts may have unusually high tides. If you saw the old
Moon this morning, calculate the time interval from your last sighting
until the time of New Moon. When you see the young Moon in the early
evening on Saturday or Sunday, calculate the interval from New Moon
until the time of sighting.

Saturday, January 20
Will anyone near the U.S. West Coast or in Hawaii see the extremely
young Moon tonight? The first *naked eye* sighting of the young Moon
determines the start of the Islamic holy fasting month of Ramadan, but
the first such sighting will be possible only from Hawaii or even farther
west. An optically aided sighting from the U.S. West Coast would set a
new record for the youngest Moon ever seen, a scant 13 hours after
New, or even less. It'll be very difficult, with the short faint lunar arc in
bright twilight within 8 degrees above the Sun. Using binoculars or a
telescope, look 20 to 25 minutes after sunset, very low in WSW, 31
degrees lower right of Venus and 6 degrees right of Mars. [But Mars
might not be visible.] Even from Hawaii, the Moon will still be only 9-
1/2 degrees from the Sun and less than 16 hours after New, but might
just be possible with unaided eye!

A westerner who catches both the old Moon on Friday and the young
Moon this evening might set an additional record for the minimum time
between "opposing crescents". From Mauna Kea, Hawaii, the ages of
the Moon at civil twilight (when the sun is 6 degrees below the horizon,
about 24 minutes before sunrise and after sunset) are -20.2 hours on
Friday morning and +15.7 hours on Saturday evening, an interval of
35.9 hours.

Sunday, January 21
The slender crescent young Moon is an easy and beautiful sight at dusk.
Look in the WSW, about 18 degrees lower right of Venus. From mid-
Michigan, the Moon's age is about 34 hours, from the U.S. West
Coast, 37 hours. Watch for the earthshine on the Moon's dark side each
evening this week. Will you still see it at week's end?

Monday, January 22
The two brightest nighttime objects, Venus and the Moon, make a
spectacular pair for three hours after sunset. Try to see Venus in the
daytime by using the Moon as a guide. Right at sunset, they're about 6
degrees apart, with Venus to the Moon's upper left. A much closer
pairing of these bodies awaits us on Feb. 21.

Tuesday, January 23
Tonight the Moon forms a pretty pair with Saturn; they're 4 degrees
apart, with Saturn to the Moon's left. Venus gleams 10 degrees below
them.

Tonight, both Earth and Sun are nearly one degree from Saturn's ring
plane, but on opposite sides. If your telescopic image of Saturn were
large and sharp enough tonight, the dark band across the face of Saturn
would be resolvable into two equal components: The rings' *shadow*,
and their *unlit face*. In coming weeks, the shadow widens and the
ring face narrows, until on Feb.11 the rings are presented exactly
edgewise to Earth and completely disappear. Beginning Feb. 12, we'll
see the *illuminated face* of the rings off to the sides of the planet, first
as a very narrow line of light, growing broader nightly.

Wednesday, January 24
By tonight the Moon climbs well above the two evening planets. Find
Saturn about 13 degrees below the Moon at dusk and some 9 or 10
degrees upper left of brilliant Venus.

Thursday, January 25
The Moon, still a crescent tonight and Friday, passes First Quarter
phase early on Saturday and will appear just over half full that evening.
These evenings, with the Moon close to half full, are ideal for using
binoculars and small telescopes to study lunar surface features.

Friday, January 26
As darkness falls, note the Great Square of Pegasus in the west, to the
upper right of Venus. Tonight Venus aligns with two stars to its upper
right, the west side of the Great Square. Look nightly and watch for the
alignment to change. On Feb. 12, Venus will line up with the two stars
on the east (trailing) side of the Square.

Saturday, January 27
By Sunday at dawn, Mercury attains first magnitude very low in ESE at
dawn. Forty-five minutes before sunup, look 14 degrees lower left of
Jupiter. Binoculars help. Mercury gets higher daily all next week and
doubles in apparent brightness by week's end.

Sunday, January 28
Countdown to the great Groundhog Day conjunction of Venus and
Saturn, the best evening pairing of planets this year: With 5 days to go,
the planets are 5 degrees apart! Face SW at dusk. Venus is the lower
and brighter.

Monday, January 29
At nightfall the Moon is nicely framed by the V-shaped head of Taurus,
which consists of first-magnitude Aldebaran and the Hyades. Use
binoculars to see the faint Hyades in the Moon's glare. Look hourly to
follow the Moon's motion against the stars. From Michigan, the
Moon's southern edge slides one degree N of Aldebaran around 1 a.m.
EST tonight.

Tuesday, January 30
Countdown to the Groundhog Day conjunction: With 3 days to go,
Venus-Saturn are 3 degrees apart!

Wednesday, January 31
Good things come in pairs! Tonight at dusk, Saturn is 2 degrees upper
left of brilliant Venus in WSW. For rest of week at dawn, locate
Mercury low in ESE, 13 degrees lower left of bright Jupiter. Look
daily.

********** end of Skywatcher's Diary for Jan 1996 **********