StarWatch: Moravian College Astronomy

DECEMBER 2000

DECEMBER STAR MAP | INDEX | MOON PHASES

223   DECEMBER 3, 2000:     Jupiter, Saturn, Moon Tango
The bad weather of last week did not prevent the exquisite conjunction of Venus and the Moon from going unnoticed. Almost like magic the skies cleared for just a few minutes during evening twilight to reveal the Moon nearing Venus on Tuesday, standing directly above her on Wednesday, and then moving to the left of Venus on Thursday. Thursday’s blustery twilight with swaying branches, holiday lights, and the heavens bedecked with the Moon and Venus provided a pleasant pause to a hectic day. And the light show will continue. If you’ve kept an eye on the Moon, you’ve noticed it’s moving eastward and gaining in brightness. During the week it will approach two other celestial gems, Jupiter and Saturn. Tonight the moon is at first quarter, half illuminated by the sun and half in its own shadow. Thereafter, it will become gibbous, "bulging from both sides" until it is full next Monday. By the end of the week Saturn and Jupiter will tango with Luna. On Friday evening, Jupiter, Saturn, and the Moon will be lined up almost equidistant from each other in the east, southeast around 8 p.m. Because the Moon will be very bright, don’t expect the planets to glisten in the same way that Venus and the Moon did last week. But they will be distinct, and the view should be impressive, especially if it is very clear. On Saturday, the Moon is again equidistant from the planets, but this time, in-between them and slightly below. Jupiter will be to the left, and Saturn to the right of the Moon. Placing a thumb over the Moon to eclipse it will reduce the Moon’s glare and render the planets easy targets. By Sunday, the Moon is to the left of the pair, with Jupiter in-between. Download a map from this week’s online StarWatch.

224   DECEMBER 10, 2000:     Christmas Eclipse
After the presents are unwrapped on Christmas morning, you and your family could be a witness to a very special astronomical event, a partial eclipse of the sun. An event such as this occurs when the moon partially covers or hides the sun. Eclipses by themselves are interesting, but a solar eclipse occurring on a holiday when virtually everyone has off from work is an unprecedented opportunity to see nature’s workings in a less harried fashion, and also get family, friends, and relatives involved. For Allentown, the Christmas eclipse begins at 11:10 a.m. Over the next hour and one half, the Moon appears to slide across the top of the sun. By 12:45 p.m., mid-eclipse, about 54 percent of the sun’s diameter will be covered by the Moon. The last eclipse of the millennium will end at 2:21 p.m., leaving plenty of time to prepare for family gatherings during the evening hours. The easiest way to view this eclipse is to purchase a pair of Eclipse Shades. Dan’s Camera City--610-434-2313 of Allentown is marketing these dark Mylar glasses as a fund raiser for the Allentown School District Planetarium. Keep in mind that you should NEVER use sunglasses, multiple pairs of sunglasses, UV (ultraviolet) absorbing sunglasses, colored cellophane, colored filters, neutral density filters (from photo stores), polarizing filters, fully exposed color negatives or fully exposed black and white (silverless) photographic negatives, or glass smoked by the soot of a candle flame to filter your direct observations of the sun. All of the above methods can cause retinal burns and vision loss. Go to the planetarium’s web site below to discover lots of other safe ways of observing the sun. We’ll continue our discussion of the Christmas eclipse next week.

See the Christmas Eclipse.   Buy Your Eclipse Shades Now!

Eclipse Shades will produce a beautiful yellow image of the sun and are safe for direct solar viewing of the December 25, 2000 Christmas eclipse. They are available for $2.00 per glasses from Dan’s Camera City, 1439 W. Fairmont St., Allentown, PA 18102, 610-434-2313. They make a great stocking stuffer or Holiday party favor. All proceeds will benefit the Allentown School District Planetarium. Eclipse Shades are NOT a toy! This product should not be used with any other optical appliances such as cameras, telescopes or binoculars. Children should always be under the supervision of an adult when using this product.

225a DECEMBER 17-21, 2000:     Long Winter Eclipse
The clock keeps ticking as sun, Moon, and Earth position themselves for the last eclipse of the millennium. This all occurs on Christmas Day, 2000. The Moon will start nibbling at the sun about 11:10 a.m., and it won’t give up the fight until 2:21 p.m. That’s 3 hours, 11 minutes. This long partial eclipse is the result of several very interesting factors. First, the Moon is very close to apogee, its farthest distance from Earth. Lunar distances range between 221,400 miles and 252,700 miles. At mid-eclipse, the Moon’s distance will be 250,600 miles or 2,100 miles short of its farthest point. The farther the Moon is from Earth, the less Earth’s gravity attracts it, and the slower the Moon moves in its orbit. Just the opposite is true for the Earth-sun distance during this eclipse. The Earth is headed for perihelion in early January. During the eclipse, we’ll be about 91.3 millions miles from the sun. Simply put, the Earth will be moving at nearly its highest orbital velocity which will be reflected in the highest rate of eastward motion of the sun in the sky. The Moon, moving at a slower than usual pace, will be catching up to and passing the sun moving at a faster than normal pace. The Earth’s rotation also plays a very significant factor in all of this. At the latitude of Allentown, we are moving at a velocity of nearly 790 miles per hour. This motion is in the same direction as the motion of the Moon, further slowing down the Moon’s shadow. Since the eclipse is happening close to local noon, these circumstances will unfold with nearly their maximum effects for the Lehigh Valley. The result will be a longer eclipse. Information about safely viewing the Christmas eclipse is provided at the web site below.

"Be real cool" with your new Eclipse Shades. Just don’t walk around the house with them on. Could these people be from Roswell? No, they're the aliens from Dieruff High School's seventh period Astronomy class. Left to Right, O'Neill Alvarez, Matt Distler, Alexandra Dunstan, Jason Jones, Nathan Brown, Sabrina Follweiler, Lucy Lawless, Wanda Rosario, Nick DiBucci (hiding), Ken Eck, Ria Castillo, and Malinda Guadalupe. Gary A. Becker photo...

225b DECEMBER 23-25, 2000:     See the Christmas Eclipse
The public excitement generated over the Christmas Eclipse became evident after Tuesday’s "Morning Call" article. Over 1500 Eclipse Shades were sold by early Tuesday afternoon. Leftover stock from previous eclipses were quickly gobbled up by an eager public on Wednesday morning. Literally hundreds of others were left without any prospect of viewing this eclipse. In an effort to help those individuals who would like to see nature at its best, Dan’s Camera City, 1439 West Fairmont Street, Allentown, is hosting about a dozen friends of the Allentown School District Planetarium who will be bringing their telescopes to Dan’s store parking lot to let everyone see this celestial spectacular. The store will be closed on Christmas. There will be telescopes which will allow direct filtered views of the eclipsed sun, as well as instruments that will be projecting the solar image onto viewing screens. The eclipse starts at 11:10 a.m. and continues until 2:21 p.m. Maximum coverage, about 54 percent of the sun’s diameter, occurs at 12:45 p.m. If you tried to purchase Eclipse Shades and were unsuccessful, here is another opportunity to see this eclipse. Drop by for a quick look or watch the entire drama unfold over the three hour, 11 minute period that the Moon will cover the sun. We will be setting up about 11:00 a.m. Contact Dan’s Camera City--610-434-2313 on Monday after 10:00 a.m. in case the weather looks doubtful. You can also log onto the ASD Planetarium’s web site noted below to receive an update after 10:00 a.m. The support for this event was outstanding, and we want to make sure that everyone who desires to see the Christmas Eclipse get a fair chance. Happy Holidays!

226   DECEMBER 26, 2000:     The Cold Christmas Eclipse
The moon and sun wait for no one. I was late, and a traffic light stuck forever on red made it even worse. By the time I arrived at Dan’s Camera City, I had only 15 minutes before first contact, the beginning of the solar eclipse. It was cold, very cold, and the assembly of my telescope gear seemed to go in slow motion, taking forever to screw a solar filter in place as fingers became quickly numbed by the cold and wind. At 11:10 a.m. it happened, right on schedule, just like my computer program had simulated it in dozens of classroom demonstrations. Matt and Marcella Gustantino of Orefield saw the first nibble of moon against sun while I was aligning my scope, and others were arriving. The celestial clockwork ticked; the dance of the heavens unfolded in precise harmony. There were no delays, no reprieves, no second chances. It was a good lesson to experience, especially since I almost always run late. About five minutes afterwards, I was focused and tracking the dance with a distinct chunk of the sun already gone. For the next three hours over a half dozen scopes entertained about a dozen volunteers and about 150 Valley residents who dropped by to witness the dance and to chat. For those who saw the Christmas eclipse, either at Dan’s or throughout the Valley, it was a testament to the human desire to behold events in real time. Sure, watching the eclipse on the Internet was more comfortable, and still commendable, but the view was from the bleachers. Those who observed the event outside saw the real photons of eclipsed sunlight enter their eyes and became true participants of the heavenly dance. They were truly onstage with the actors as the moon courted the sun. Bravo! A special thanks is extended to Dan Poresky, owner of Dan's Camera City, for allowing this event to take place at his store parking lot, as well as the other volunteers who supported this event: Matt and Marcella Gustantino, John and Jane Sumerfield, Jesse Laufer, Jesse Leayman, Rosa Salter, Fran Kittek, Fred Bomberger, and John Weinhold.

227   DECEMBER 31, 2000:     Highlights for 2001
What is in store for us during the year 2001? The first item to be addressed is that 2001 marks the start of the new millennium. Don’t worry about all of the advertising hype of last year. The third millennium begins on January 1, 2001. The first full moon of the new millennium, January 9th, will bring with it a total lunar eclipse. It will be an early evening event for Europe, but for us, the moon will rise as it is leaving Earth’s main shadow cone. Look for a weird full moonrise in the ENE around 4:55 p.m. on the 9th. Throughout most of this year, some very bright planets will be dominating the evening sky. During January, February, and March, Venus (west) and Jupiter and Saturn (south) will bring added sparkle to the bright winter constellations. By the end of March, Venus will be gone, but Jupiter and Saturn will continue to be visible low in the west after sundown. By June, Mars will take center stage. It will be very low in the sky throughout the summer, but this will be easily compensated by Mars’ brilliance and color, the best show in the last 13 years. Mars will remain visible throughout the early evening hours during the fall and early winter. By the start of November, look for a more widely separated Saturn and Jupiter to be visible low in the east. These two giant planets will dominate the winter sky of 2002. On November 3rd, 45 minutes before sunrise, Venus and Mercury will be separated by only 2/3 degree. Then on the morning of November 18th, watch out for another strong Leonid meteor display, near dawn. The East Coast is a favored target zone, just like last year. Keep vigilant for above normal auroral displays during 2001, since sunspot activity will be remaining high.