StarWatch for the greater Lehigh Valley



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[Moon Phases]


336    FEBRUARY 2, 2003:   A Very Bad Day
I now have three horrible video clips that keep looping in my mind. The first was the Challenger disaster of 1986, when 70 seconds into the launch sequence, the shuttle and its boosters disintegrated, leaving the astronaut's pressurized cabin tumbling out of control until impact into the Atlantic several minutes later. The second was a series of news clips showing the attack and collapse of the World Trade Center nearly 17 months ago. This morning, the third horrible video clip was imprinted into my brain as I watched and listened to CNN's coverage of the disintegration of Columbia over north central Texas. Everyday tens of thousands of people die horrible deaths from disease, starvation, and accidents. Forty percent of all Africans will be dead within the decade from AIDS, but the individual stories of common people rarely command a great deal of media attention. However, when astronauts die, the world pauses and cries. Everyone creates his or her own horrific portrait of what those last lonely seconds were like. Challenger and Columbia have once again reaffirmed the obvious to anyone who is even remotely connected to spaceflight. The exploration of the cosmos is an extremely dangerous enterprise, in fact, the most hazardous venture that humanity has ever attempted. Keep in mind that the Space Shuttle is the most complicated flying machine that humans have ever created and understand that other brave astronauts will sacrifice their lives in our conquest of space. But for now, I too am numbed and need to pause and reflect upon what has happened on this gray morning. One thing is for sure; we will need to fly again soon. The International Space Station continues to operate with a crew of three astronauts who also will need our support.

337    FEBRUARY 9, 2003:   Less Than a Heartbeat
I have hiked Mt. Washington in northern New Hampshire and found myself in sustained winds of 80 mph gusting to 100 mph. My ground speed was probably less than one mile per hour. I can tell you that navigating under these circumstances is a precarious balancing act of adjustments against the buffeting wind that quickly saps your energy and makes you wish that you were at home and in the warm arms of your loved one. The human body dressed in Gortex with a 40-pound pack and ice axe is not exactly aerodynamic. Flash... We're now in Columbia just over 39 miles above the earth's surface traveling at 2.4 miles per second. The shuttle is punching through the atmosphere at over 8500 mph, although the atmospheric pressure is only 1/5000 that of sea level. Our ship is aerodynamically constructed and works flawlessly as long as it is pitched at just the precise angle to allow an even airflow to firmly and continuously break its forward motion. As the shuttle descends through thicker atmosphere, the pitch of the vehicle is decreased, keeping the deceleration constant until the shuttle glides to a landing at Cape Canaveral. Somewhere over California, it appears that drag on the left wing of Columbia began to increase, meaning that the left side of the vehicle was slowing at a faster rate than the right side. For a while onboard computers would have been able to automatically compensate by increasing the drag on the right wing and lessening it on the left. But somewhere over north central Texas, traveling at 2.4 miles per second, the onboard computers were no longer able to stabilize the shuttle and Columbia probably spun out, tumbled, and disintegrated all within the time span of a few seconds. The astronauts probably died in less than a heartbeat.

338    FEBRUARY 16, 2003:   The Stars of High Winter
Have you noticed the days lengthening and that extra bit of afternoon warmth trapped in your car by the time you leave work? The next 60 days are going to see some major changes-nearly 2-1/2 hours more daylight, and the sun climbing over 20 degrees higher in the sky at noon. It is also that transition period when we can get some of our biggest snowfalls; so don't think that this is any prognostication for an early spring. I call this the time of high winter because, if you venture out of doors right after dark, the winter group of constellations will be spread out before you like a splash of bright glitter high in the south. Orion, the Hunter, is the centerpiece with its three tipped belt stars, Mintaka (top), Alnilam (middle), and Alnitak (bottom) pointing downward towards Sirius, the brightest luminary of the night and upward to Aldebaran, the reddish eye of the Bull. Continue past the eye to the Pleiades nestled on Taurus' shoulder like a tiny patch of frozen breath in the cold night air. Orion's red shoulder star, Betelgeuse, and diamond blue, Rigel, sling you upward to mortal Caster and immortal Pollux, the two faithful Gemini Twin brothers. To their left is brilliant Jupiter. Above Orion lies Saturn, and nearly scraping the zenith is Capella of Auriga, the Charioteer. They won't be around for too much longer, so catch them while you can. Not only does the daily plodding of earth's position around the sun cause these star patterns to set four minutes earlier each night, but the later sunsets also brings these same stars into visibility later each evening. The rapid changes that will herald the onset of spring will also be manifested in just as rapid a exiting of the old guard. See a photo of winter's finest in this week's web edition of StarWatch at the URL listed below.
[Winter's Finest]

339    FEBRUARY 23, 2003:   Sundogs
Over the past several years I have had the opportunity of discussing optical effects of the sun and moon associated with ice crystals, namely the 22-degree lunar and solar halos that are a fairly common winter phenomena, as well as solar pillars which are only seen around sunrise and sunset. See my StarWatch articles for November 24, 2002 and February 27, 2000 at the URL listed below. Another low-sun optical effect connected to ice crystals is the sundog, a marked spectral brightening in the sky at an angle of 22 degrees from the sun but appearing more intense than the solar halo. The halo results from the refraction (bending) of sunlight through pencil-shaped ice crystals. The minimum angle of refraction is 22-degrees. This insures a defined inner edge, but a diffuse outer boundary since the ice crystals are rotating, and the angle of the light entering the crystals is continuously changing. For the complete halo to be visible, the orientation of the pencil-shaped ice crystals must be random. Crystals that are precisely at the correct angle to refract light back to the eye create each part of the complete circle. But when the sundog is fashioned, the pencil or hexagonal plate crystals are falling through the air with their long axes on end. The crystals line up like marching soldiers (lllllll) to create just a small but brilliant portion of the 22-degree halo. Only when the sun is low in the sky will the pencil crystals appear vertical enough to the observer's line of sight to create the phenomenon, so don't expect to see sundogs in the middle of the day. Also keep in mind that every halo, sundog, pillar, and rainbow is unique. The people standing next to you see their individual halo or bow created by a different set of crystals or raindrops. A sundog photo is posted at Web StarWatch.
[Sundog near Flagstaff, AZ]
Sundog near Flagstaff, AZ:  Gary A. Becker, located north of Flagstaff, Arizona digitally photographed this summer sundog near sundown on June 24, 2002. The "dog" on the right is brighter than the one on the left near the top of the pine tree. The left dog, however, shows the reddish inner boundary which is characteristic of sunlight refracted through ice crystals and water droplets. The large tree in the center of the photograph was used to block out the sun.

February Star Map

February Moon Phase Calendar