StarWatch for the greater Lehigh Valley

AUGUST  2000


206   AUGUST 6, 2000:     Summer's Last Rite
The dog days of summer are upon us and despite the increasing brightness of the moon this week, it is still time to consider observing one of the best known meteor showers of the year. Watching Perseid meteors is almost like a last rite of summer. Once they are gone, it’s onto Labor Day, and well you know the rest. The best night for watching will be on Saturday evening--Sunday morning, August 12-13. Unfortunately, that night will be closest to the full moon which happens on the 15th. Observations should occur after the moon sets because sky conditions will be at their darkest. Moonsets this week occur at 12:17 a.m. Monday, 12:49 a.m. Tuesday, 1:24 a.m. Wednesday, 2:03 a.m. Thursday, 2:47 a.m. Friday, 3:36 a.m. Saturday, and 4:28 a.m. Sunday. Perseid meteors will appear to diverge from the top of the constellation of Perseus, the Hero. Above Perseus is the better known constellation of Cassiopeia, Queen of Ethiopia. Cassiopeia appears like a sideways "W," with the open ends pointed to the left. Perseus will look like a large up-side-down "V." By midnight the radiant, the location from which the meteors will appear to be diverging, will be located over one third of the way up in the NE sky. By 2:00 a.m., look NE about mid-sky, and by 4:00 a.m., the radiant will be in the ENE, two thirds of the way up in the sky. The higher the radiant, the more meteors you will be able to see. When the radiant is low, most of the meteors that flash below this point are missed, and rates are considerable lower. Also after midnight the Earth rotates into the oncoming meteors and more are seen. A sleeping bag, lawn chair, warm drink, and a plastic tarp for dew protection will improve your meteor observing comfort.

Perseid Meteor Map

207   AUGUST 13, 2000:
Chaco Culture National Historical Park, located about 150 miles to the NW of Albuquerque, NM, possesses an astronomical observatory with research capable equipment coupled with an ongoing volunteer outreach program to help visitors become acquainted with the night sky. Chaco’s Night Sky Initiative began in 1991 when the Park added the dark sky to its list of natural resources to be protected. At that time it also began to offer a strong astronomy component in its public interpretive programs, in addition to its strong archaeology program which has emphasized the Native American Chacoan culture which dominated NW New Mexico between 850 and 1140 AD. Public programs emphasize the astronomical practices of the Chacoan people a thousand years ago, as well as modern approaches to viewing the same night sky they viewed--in a remote environment free from urban light pollution. Chaco’s Night Sky Initiative got a real boost in 1998 when Albuquerque amateur, John Sefick, donated $40,000 of astronomical gear to the Park. Chaco responded by constructing buildings to house this equipment which included a domed observatory, computer room, and an amphitheater for large group programs. Needless to say, the observatory and its telescopes comprise "the best show in town" after darkness falls. Visitors get to participate in a true dark sky experience. You can find out much more about Chaco’s Night Sky Initiative by logging onto the web site noted below and clicking on the Chaco button. Chaco’s astronomy home page, will go independent by mid-September, but Lehigh Valley residents can view this educational resource now. logo

208   AUGUST 20, 2000:     How dark is dark?
I remember being “trapped” in Sennufer’s tomb, mayor of Thebes in Amenophis II’s reign (18th Dynasty; 1427-1397 BCE), located in the Valley of the Nobles on the West Bank of the Nile at Luxor. The tomb guard, equipped with his kerosene lantern, had disappeared upstairs for “just a moment,” and my wife and I were left in complete darkness and silence for what seemed to be an eternity, but it probably was no more than 10 minutes. We were in the heart of Egypt’s greatest necropolis and that was the scariest dark I have yet experienced. The night sky is never that black, for stars, planets, and even the sky itself gives off a sufficient quantity of light for the fully dark adapted eye to distinguish a myriad of details on the ground. So how dark can it get? In New Mexico and Utah, where I have done most of my summer observing, I have regularly noticed shadows being cast by Venus. I had read about Jupiter being able to accomplish this same feat, but it was not until August 2000 that I made that observation from Chaco Canyon, NM. High in the eastern sky about 4:30 a.m. was Jupiter, Saturn, the Pleiades, Taurus the Bull, and Orion the Hunter beginning his leap over North Mesa. What a glorious sight! My shadow was plainly visible on the ground pointing away from Jupiter. Astronomers say the darkest skies in the world occur in the Australian Outback where the Milky Way is so brilliant that it can cast diffuse shadows on the ground. I witnessed this for myself in the Australian Bush at Siding Spring National Observatory in February 2001. Not only did the brilliant southern Milky Way provide enough illumination to discern ground detail easily, but I was also able to read the lettering on my Mt. Washington sweatshirt. These were surely nights to be treasured and remembered forever. Revised February 13, 2008

209   AUGUST 27, 2000:     Sea Goat
The nights are getting longer. Over the next 60 days, the time that the sun spends below the horizon will increase by roughly 160 minutes. We are at the precipice of that great slide that leads to the dark of winter. However, summer isn’t over quite yet, but the sky is beginning to put on its autumn venue. If you venture out about 9:00 p.m., you’ll still see the summer stars shining strong. Sagittarius, the Archer lies due south low to the horizon. But his enemy Scorpius, the Scorpion, is beginning to straddle the SW horizon and is completely gone by 11:30 p.m. By then Sagittarius will look more like a teapot, pouring its hot drink. The glow of the Milky Way will act as warming steam rising above the spout. East of the Teapot the heavens may appear to be blank. From the country with the unaided eye, or in more light polluted areas with binoculars, you’ll notice a large sweep of faint stars that looks triangular in shape, something like the Star Trek insignia worn by the original Enterprise crew. You’ll be looking at Capricornus, the Sea Goat. So why not just a regular goat? Capricornus lies in the water part of the sky, keeping company with Aquarius, the Water Bearer; Delphinus, the Dolphin; Pisces, the Fish: Cetus, the Whale; Pegasus, the Flying Horse, Eridanus, the River; and last and yes least, Piscis Austrinus, the Southern Fish. The idea of a goat, however, is rather ingenious. Several thousand years ago when the sun reached its lowest position in the sky, at the time of the winter solstice, this event occurred in the area of Capricornus. Afterwards the sun began to climb higher in the sky each day. Goats are great climbers, and well, why not a sea goat to stay with the water theme.

August Star Map

August Moon Phase Calendar