Abrams Planetarium

SKYWATCHER'S DIARY: January 1997

To the reader

The Skywatcher's Diary for January 1997 has been prepared by Robert C. Victor. Sometimes you can see next month's in advance by looking in our archives. Credit to Abrams Planetarium, Department of Physics and Astronomy at Michigan State University, together with mention of our Sky Calendar, would be appreciated.

A sample back issue of Sky Calendar is available over the Internet. It can be viewed via a World-Wide Web browser such as Netscape or Mosaic, directly at URL:

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

If you would like a printed sample, send a long, self-addressed stamped envelope to:

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

Each month, the Department of Physics and Astronomy at Michigan State University also makes Skywatcher's Diary available over the Internet. It can be accessed via a World-Wide Web browser such as Netscape or Mosaic, directly at URL:

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

The Skywatcher's Diary is also available via anonymous ftp at: www.pa.msu.edu in the directory /pub/swd

ftp://www.pa.msu.edu/pub/swd/

Comet Hale-Bopp Resources
Comet Observation Home Page (JPL/NASA): http://encke.jpl.nasa.gov/
Sky Online's Comet Page: http://www.skypub.com/comets/comets.html
Press Info on H-B: http://cfa-www.harvard.edu/cfa/ps/HaleBopp.html


Wednesday, January 1

An hour before sunup on Thursday, face south to find Spica 7 degrees to Moon's lower left. The Moon is just under half full. Mars is in SSW 17 deg to Moon's upper right.

Thursday, January 2

In the predawn hours of Friday, the Quadrantid meteors may reach a strong peak. An hour before sunup, face south for Spica 7 degrees to Moon's right. Look very low in SE for bright Venus with Antares, heart of the Scorpion, 13 deg to its upper right.

Friday, January 3

From now until late March, Comet Hale-Bopp is a morning object. About 1-1/2 hours before sunrise, locate bright Vega in ENE. Comet H-B is very low in E, 33 degrees lower right of Vega, 20 degrees lower left of the 2nd-mag star Alpha in Ophiuchus, and 9 degrees lower right of the 3rd-mag star Zeta in Aquila. Use binoculars. From one morning to the next, Comet Hale-Bopp now shifts its position against the stars by half a degree per day. Getting a little higher each morning, and possibly brightening through 3rd mag this month, Comet H-B may soon become a naked eye object for billions of viewers in Earth's northern hemisphere.

Saturday, January 4

An hour before sunrise on Sunday, look SE for a beautiful crescent Moon with Antares twinking 15 degrees lower left. Bright Venus is 15 degrees lower left of Antares.

Sunday, January 5

On Monday an hour before sunrise, the crescent Moon is in SE. Look for Antares, "rival of Mars," 8 degrees to Moon's lower right, and bright Venus 15 deg to Moon's lower left. In three months, on April 2, Venus will be almost directly behind the Sun.

Monday, January 6

Last easy chance to view the old Moon! On Tuesday an hour before sunrise, look very low in ESE to SE for the thin crescent with Venus just 4 degrees to its lower right.

Tuesday, January 7

Forty to 30 minutes before sunrise on Wednesday, try for the very old Moon rising in ESE. First locate Venus, then, using binoculars, look for faint 1.5-mag Mercury 7 degrees to its lower left. From the East Coast, the hairline-thin crescent is 5 degrees lower left of Mercury and 16 to 17 hours before New. From the West Coast, the more difficult Moon is 7 degrees lower left of Mercury and only 13 to 14 hours before New. Bagging the old Moon is easiest in Southeast U.S., most difficult in the Northwest. When you last spot the Moon, note the time and calculate the time interval remaining until New. The New Moon (its conjunction with Sun) occurs today at 11:26 p.m. EST (8:26 p.m. PST).

Will anyone see the "opposing crescents", of Wednesday morning and Thursday evening? Note the times of your last sighting of the morning crescent and first sighting of the evening crescent, instruments used, and send a report to: Moonwatch Jan. '97, c/o Abrams Planetarium, Michigan State University, East Lansing, MI 48824.

To prime yourself for these delicate Moons, see the following articles in Sky & Telescope: "Sighting the Opposing Crescents" in May 1995, page 105; and "In Quest of the Youngest Moon" in December 1996, page 104.

Wednesday, January 8

On Thursday about 45 minutes before sunup, locate Venus very low in SE sky. Mercury (mag +1.2) is visible in the same 7-power binocular field, 5.5 degrees to Venus' lower left. Mercury is getting higher and brighter each morning, and will pass 4 degrees left of Venus on Jan. 10, and within 3 degrees upper left of Venus on Jan. 12.

Improve your chances of spotting the Ramadan Moon of Jan 9

Thursday, January 9

Within half an hour after sunset, the very young Moon is very low in WSW, and likely to be seen with unaided eye. Its age (time elapsed since New) is less than 18 hours from the Northeast U.S., about 19 hours from Florida, and 21 hours from the West Coast. For the 48 states, this is an easier sighting than the very old Moon of Wednesday morning.

This month's young Moon is of special significance to a quarter of the world's population. The first glimpse of the slender crescent marks the beginning of the Islamic holy fasting month of Ramadan. Try these two websites for more info on the Ramadan moon:

http://www.erols.com/shaukat/sksmoon.html
http://www.ummah.org.uk/ildl/

Friday, January 10

Tonight's nearly 2-day-old crescent is very easy to see, low in SW to WSW at dusk. The Moon sets in a dark sky, over two hours after sunset. Very low in SE 45 minutes before sunrise Saturday through Monday, Mercury is 3 degrees upper left of Venus.

Within the next few months, a lunar eclipse, Comet Hale-Bopp, and Mars are all slated to put on a fine display in the evening sky. Jupiter, Saturn, and Venus come along later in the year. Beginning tonight, our new show, Celestial Preview 1997, gives tips on how to view these and other phenomena, using Abrams Planetarium's Digistar projector. You'll emerge with an increased enjoyment and appreciation of the ever-changing sky scene. Celestial Preview 1997 is presented two weekends only, January 10-12 and Jan. 17-19, on Fridays and Saturdays at 8 p.m., and Sundays at 4 p.m.

Saturday, January 11

On Sunday, very low in SE 45 minutes before sunup, Mercury passes 2.7 degrees upper left of Venus. This is their closest visible pairing with each other until August 1998.

Sunday, January 12

Note the large, nearly isosceles triangle formed by Arcturus, Mars, and Spica these mornings. Look for it low in eastern sky 6 hours before sunrise, and high in southern sky one to two hours before sunup. The Big Dipper's curved handle leads directly to Arcturus at the northern apex of the triangle. For the next several weeks, the triangle changles little in shape, with Arcturus about 33 degrees from both Spica and Mars. But watch Mars increase in brilliance, outshining zero-magnitude Arcturus by month's end.

Monday, January 13

Locate the waxing crescent Moon well up in SSW at dusk. The first- magnitude "star" a few degrees left of the Moon is Saturn. A telescope reveals the rings, still tipped less than 4 degrees from edgewise.

Very low in Tuesday's SE morning sky, three-quarters of an hour before sunup, Mercury stands within 3-1/2 degrees above Venus.

Tuesday, January 14

At dusk the fat crescent Moon is in SSW with Saturn 11 degrees to lower right.

Today the location of Comet Hale-Bopp in space is higher above the Earth's orbital plane than any any time between its last visit to the inner solar system some 4200 years ago and its next visit some 2400 years from now. Today the comet's distance north of the ecliptic plane is 1.20 astronomical units, or nearly 112 million miles. (The astronomical unit, defined as the mean distance from Sun to Earth, is the standard unit used to measure distances within the solar system. One a.u. is approximately 92.956 million miles.) Of its vast orbit, Comet Hale- Bopp spends only a little over over 14 months --from late February 1996 to early May 1997 -- above the plane of Earth's orbit, which will give Earth's northern hemisphere residents the best view of Hale- Bopp's current visit to the inner solar system. Stay tuned!

One-and-a-half hours before sunup on Wednesday and Thursday, Comet Hale-Bopp is due east, about 12 degrees up. Start with bright Vega well up in ENE. The comet is about 30 degrees lower right of Vega and 5 degrees lower right of a 3rd-mag star, Zeta in Aquila. Comet and Zeta fit into a single field of view of 7-power binoculars. Look for a faint tail extending to the upper left. Seen just last week at a brightness of 3rd-magnitude, Comet Hale-Bopp is on track to put on a good morning display in February and March, and an even better evening show in late March and early April.

Starting an hour before sunrise, watch the horizon between ESE and SE for Venus rising 4 degrees lower left of Mercury. At the same time relative to sunrise on each successive morning, Mercury will be seen about the same height above the horizon for another week, while Venus gets lower daily. On what date will you last see Venus before it passes the far side of the Sun in early April?

Wednesday, January 15

This afternoon and early evening, the Moon is near First Quarter phase, half full and 90 degrees or one-quarter circle east of the Sun. If you face the setting Sun this evening, the Moon will appear over your left shoulder. Notice the Moon's right half (the side toward the Sun) is illuminated. These evenings with Moon near half full are ideal for viewing the Moon with binoculars and small telescopes to study lunar surface features.

Thursday, January 16

One and a half hours before sunrise in coming weeks, these bright stars of the Summer Triangle will be helpful for locating Comet Hale-Bopp: Bright Vega, well up in ENE; Altair, low in E, 34 degrees to Vega's lower right; and Deneb in NE, 24 degrees to Vega's lower left. For the next few mornings, Comet Hale-Bopp is about 13 degrees up in E, 10 degrees upper right of Altair and 30 degrees lower right of Vega. As a check, H-B is about 4 degrees lower right of a 3rd-magnitude star, Zeta in Aquila, the Eagle. The comet is currently about 3rd magnitude and changing its position against background stars by 0.6 degrees per day.

Look for three planets about an hour before sunrise: Mars well up in SW, 34 degrees lower right of Arcturus which is even higher in the south. Can you detect that Arcturus twinkles but Mars shines with a steady light? Compare color and brightness of Arcturus and Mars in coming weeks. Mercury is very low in ESE to SE, with Venus just rising 5 degrees to its lower left.

Friday, January 17

At nightfall, about 1-1/2 hours after sunset, the waxing gibbous Moon is high in SE and nearly 3/4 full. The Pleiades star cluster is 10 degrees to Moon's upper left, and first-magnitude Aldebaran 15 degrees to lower left. With the faint stars of the Hyades nearby, Aldebaran completes a V-shaped pattern representing the head of Taurus the Bull. The entire "V" easily fits within the field of 7-power binoculars. Look again on Saturday night.

Comet Hale-Bopp is now brightening in the morning sky. Within the next few months, the comet, Mars, and a lunar eclipse are all slated to put on a fine display in the evening sky. Jupiter, Saturn, and Venus come along later in the year. Michigan State University's Abrams Planetarium presents Celestial Preview 1997, giving tips on how to view these and other phenomena. The show concludes this weekend, January 17-19, on Friday and Saturday at 8 p.m., and Sunday at 4 p.m.

Saturday, January 18

Starting at dusk, note the Moon's motion with respect to Aldebaran at least once per hour. Tonight, the mountainous S edge of Moon grazes Aldebaran as seen along a narrow track passing N of Vancouver by 10 p.m. PST, then western provinces of Canada just N of the U.S. border, then into ND, northern MN, northern MI, Ontario, northeast NY, southern VT, into MA and passing near Boston and Cape Cod just before 2 a.m. EST Sunday. For a map of this track and more information about similar events in 1997, see January issue of Sky & Telescope magazine, page 90. From N of this "grazeline," Moon occults (covers) star; seen from S of line, Moon misses star. From lower Michigan, the Moon's southern edge narrowly misses the star within a few minutes after 1:40 a.m. EST. As seen with unaided eye, the star may be lost in the Moon's glare, but binoculars will show it.

By comet viewing time Sunday morning (about 1-1/2 hours before sunrise), for the first time in over 4000 years, Comet Hale-Bopp's distance from Sun is smaller than the average solar distance of Mars, 1.52 a.u. or 142 million miles. Look for the comet low in east, 9 degrees upper right of the first-magnitude star Altair and 4 degrees lower right of the 3rd-magnitude star Zeta in Aquila. Comet H-B will continue falling in toward the Sun until perihelion on the evening of March 31, when it will close to only 0.914 a.u. or within 85 million miles of the Sun. The comet is bound to become more active as it closes in on the Sun, and to brighten! Stay tuned!

Sunday, January 19

At nightfall the Moon is high in ESE. Three reddish stars are not far from the Moon tonight: Aldebaran, eye of Taurus, 10 degrees to Moon's upper right; Betelgeuse, shoulder of Orion, 13 degrees below; and Pollux, one of the Gemini twins, 35 degrees to Moon's lower left.

Monday, January 20

At nightfall (1-1/2 hours after sunset), the Moon is well up in eastern sky. Betelgeuse and Rigel, Orion's two brightest stars, are 11 degrees and 30 degrees to Moon's lower right. Compare their contrasting colors. The Hunter's striking 3-star belt is about midway between them. Follow the belt downward to Sirius, the brightest nighttime star. Procyon, low in E, completes the nearly equilateral Winter Triangle with Sirius and Betelgeuse.

Tuesday morning is the last chance to see Comet Hale-Bopp without bright moonlight, until Feb. 1 when the Moon will wane to less than half full. On Tuesday 90 minutes before sunrise, look for the comet 15 degrees up, due east, and 8 degrees upper right of the first-magnitude star Altair and 4 degrees below a 3rd-magnitude star, Zeta in Aquila.

On Tuesday morning, Comet Hale-Bopp will be 205 million miles from Earth, 139 million miles from Sun. These distances will close to 122 million miles from Earth on March 22, and 85 million miles from Sun on March 31, respectively. For the next few months, the Abrams Planetarium Sky Calendar will feature dayboxes and evening star charts to help you enjoy following the progress of the comet. A subscription may be ordered for $7.50 per year, from Abrams Planetarium, Michigan State University, East Lansing, MI 48824. The February through April issues are now available.

Tuesday, January 21

An hour after sunset, the Moon is in the east with Procyon 15 degrees below. About the same distance to Moon's left are the Gemini twins: Pollux, with Castor 4-1/2 degrees to its upper left.

Wednesday, January 22

With the Moon not quite Full, this is the last chance in this lunar cycle to see the Moon and setting Sun simultaneously. Watch the ENE horizon about half an hour before sunset for the rising Moon. About an hour after sunset, the Moon is still north of east, with bright Procyon 11 degrees to its lower right, Pollux 12 degrees to Moon's upper left, and Castor 4-1/2 degrees to Pollux's upper left. In the ESE, 26 degrees to right of Procyon (and a few degrees lower for all except southernmost U.S.) is Sirius, the Dog Star. As a check, extend Orion's belt 22 degrees downward to locate this brightest of nighttime stars.

Thursday, January 23

The Moon, now just past Full, rises in ENE 20 to 30 minutes after sunset for most of the contiguous 48 United States. The Full Moon of January is called the Moon after Yule, according to astronomy author Guy Ottewell. For the rest of January, the waning gibbous Moon brightens the morning sky, affecting comet viewing somewhat, but by Feb. 1 the Moon will be less than half full.

An hour before sunrise on Friday, Mercury appears farthest from the Sun this time around, 25 degrees. Look very low, between ESE and SE. Wait about 15 minutes, then watch for the rising of Venus, 8 degrees to Mercury's lower left. Venus is now in the background, on the far side of its orbit, farther from us than Mercury is.

Friday, January 24

The Moon, just past Full, rises about 15 degrees N of due east shortly before the end of evening twilight and brightens the sky for the rest of the night. By three hours after sunset, the Moon is high enough in the east to allow you to see Regulus, heart of Leo, 9 degrees to its lower left. By 1-1/2 hours before sunup on Saturday, Moon is in west with Regulus 6 degrees above. Bright, steady orange Mars is in SW 40 degrees to Moon's upper left. Spica is in SSW, 19 degrees to Mars' lower left. High in south 33 degrees from both Mars and Spica, and marking the pinnacle of an isoceles triangle it forms with them, is bright orange Arcturus.

Can you see Comet Hale-Bopp in the moonlight? Look for the first- magnitude star Altair nearly due east, low above horizon. H-B is 7 degrees above Altair and slightly right, or almost directly above Altair from southern U.S.

Tonight From Stardust to Life: A Cosmic Journey returns to Abrams Planetarium. For show times and ticket prices, call (517) 355-4672.

Saturday, January 25

Now that Moon rises 2 hours (southern U.S.) to nearly 2-1/2 hours after sunset, there's a brief "window" of very dark skies right at nightfall. From a very dark place with no sizeable source of light pollution to the west of you, try for something most North Americans never see. Tonight through February 8, and again February 24-March 9, starting about 1-1/4 to 1-1/2 hours after sunset, look for a tall, softly luminous cone of light tapering upward from the WSW horizon: the Zodiacal Light! The base of the cone is just above the thickest horizon haze, and the axis near the ecliptic, or pathway of the Moon and planets. From southernmost U.S. at this time of year, the cone of light will be nearly vertical; from northern U.S. it is tilted left, or south of vertical. Can you follow the Zodiacal Light as far as Saturn, 57 degrees from the Sun tonight? The Zodiacal Light is sunlight reflected by dust in the plane of the solar system.

Light pollution from the proliferation of poorly designed outdoor lighting can render the beauty of the Milky Way, Comet Hale-Bopp, and the Zodiacal Light completely unobservable to the majority of our population. The International Dark-Sky Association is a non-profit, membership-based organization whose goal is to be effective -- through education about (a) the value and effectiveness of quality nighttime lighting and (b) solutions to the problems -- in stopping the adverse environmental impact of light pollution and space debris. They are making a difference and are worthy of your support!

The IDA can be reached by postal mail at 3545 N. Stewart Ave., Tucson, AZ 85716, USA. The IDA homepage on the World Wide Web is:

http://www.darksky.org/~ida/

Another excellent website is Fred Schaaf's Light-Pollution Notes, at:

http://www.skypub.com/lpnotes/lpnotes.html

To find out the locations of the best and worst viewing sites in your part of the country, follow IDA's links to images and satellite imagery. Through these links you can call up an image of your own state at night showing the areas of light pollution. As an example, in lower Michigan, satellite photos reveal the darkest skies to be in the northeastern Lower Peninsula, not far from Alpena. Each year, a loosely-knit group of amateur astronomy enthusiasts that calls itself SMURFS (the Southern Michigan Unorganized Regional Federation of Stargazers) has a summer stargazing weekend there.

Here are some quotes from Fact Sheet on the International Dark-Sky Association:

"The human experience of the inspiring beauty of the cosmos is at risk for all people, not just scientists, as light pollution destroys our view of the beautiful dark sky.

"Quality lighting is the key to overcoming light pollution. It means better visibility at night, freedom from glare, and also a great deal of energy savings. Everyone wins".

Continuing with the night of Saturday, January 25, once the Moon has risen (after end of evening twilight) look for Regulus, heart of Leo, about 5 degrees to Moon's upper left. By 1-1/2 hours before sunup on Sunday, Moon is in WSW with Regulus 8 degrees to right.

Comet Hale-Bopp is then low in east, passing 7 degrees directly above Altair as seen from northern U.S. early in the week. For rest of month, comet is moving 0.7 degree per day, staying within 7 degrees of Altair and ending to the star's upper left. (The field of view of 7-power binoculars is about 6 or 7 degrees wide.) Comet viewing will improve as scattered light from the Moon decreases daily. Moon will wane to less than half full by Feb. 1.

Sunday, January 26

One-and-a-half hours before sunrise on Monday, bright Mars is in SW, 17 degrees to Moon's upper left. Note Spica 19 degrees to Mars' lower left. Follow the Moon's motion past Mars and Spica through Thursday morning. At the same time ahead of sunrise on Monday, Comet Hale- Bopp is in east 7 degrees directly above Altair as seen near latitude 43 degrees north. From southern U.S. the comet now appears to the upper left of star.

An hour before sunup, Mercury has risen between ESE and SE. Another 15 minutes later, watch for the rising of Venus 8 degrees to Mercury's lower left. Venus is especially difficult to observe from northern states as its rising time moves ever closer to sunrise.

Monday, January 27

About 5 hours after sunset, Mars is rising nearly due east, about 8 degrees to Moon's lower left. About 1-1/2 hours before sunup on Tuesday, the waning gibbous Moon is in SW, with Mars 6 degrees upper left. Note Spica 23 degrees to Moon's left. Comet Hale-Bopp is then low in E, directly above Altair as seen from northernmost contiguous U.S. (latitude 49 degrees north), and to Altair's upper left as seen from farther south in U.S., and to the star's upper right as seen from Alaska and most of Canada. Tuesday, January 28

Tuesday, January 28

Six hours after sunset, the waning gibbous Moon, about three-quarters full, is low in E to ESE with Mars about 5 degrees above. About 1-1/2 hours before sunrise on Wednesday, Moon is in SSW between bright reddish Mars and the first-magnitude bluish star Spica.

Wednesday, January 29

On Thursday and mornings, about 1-1/2 hours before sunrise (before any significant dawn brightening is visible), locate the Summer Triangle in NE to E. The highest and brightest of its stars is zero-magnitude bluish Vega, high in ENE. First-magnitude Deneb is in NE, 24 degrees to Vega's lower left. First-magnitude Altair is low in E, 34 degrees to Vega's lower right. Comet Hale-Bopp these two mornings is located along one side of the Triangle, 7 degrees to upper left of Altair and one- fifth of the way toward Vega.

At the same time on Thursday morning, the waning gibbous Moon is in SSW with Spica 3 or 4 degrees to its lower right. Bright Mars is with 20 degrees to their upper right.

Thursday, January 30

One-and-a-half hours before sunup on Friday, the Moon is in the south. Look for three bright reddish objects, each just over 30 degrees from the Moon: Mars in SW, zero-magnitude Arcturus high above the Moon, and first-magnitude Antares low in SSE. Which of the three reddish objects is the brightest?

Friday, January 31

If you're at a very clear, dark site in the middle of the night before the Moon rises, try for the Gegenschein (German for Counterglow), or faint oval patch of light reflected from comet and asteroid dust in the direction 180 degrees from the Sun. At this time of year, the Gegenschein is ideally placed in the faint constellation Cancer, the Crab, which contains no bright star, planets, or Milky Way whose brilliance would make the faint glow impossible to detect. Look for an oval cloud some 10 degrees long, inside the triangle formed by Pollux, Procyon, and Regulus. Use averted vision: Look to one side of the cloud to place its image on a more light-sensitive part of your retina than if you looked directly at it.

On Saturday and all next week, in east 1-1/2 hours before sunrise, Comet Hale-Bopp passes through the lower right corner of the Summer Triangle 7 to 11 degrees upper left of Altair. The Moon on Saturday is just a fat crescent, getting thinner each morning and allowing darker skies for viewing Comet Hale-Bopp. By Feb. 5 the Moon will be just a thin crescent on ESE horizon as morning twilight begins. During Feb 6- 19, there will be no Moon in sky at all during comet's predawn viewing time. Astronomers expect Comet Hale-Bopp to brighten and its tail to lengthen dramatically in February as the comet closes in on Earth and Sun.


Full Graphics
Full Graphics version of this page

HTML automatic by swdmarker.pl Wed Nov 27 15:09:11 EST 1996 by Michael. Additional HTML 29 Dec 96 by Jenny/ pon@dirac.pa.msu.edu