Partial Solar Eclipse.

Stand in Moon's shadow to see cosmic ballet.

by Tom Seddon

Special to the Daily News

    On Thursday, July 11, the cosmic ballet of sun, earth, and moon reaches a spectacular climax.  The moon, as it pirouettes around the earth, will align perfectly with the sun causing a total solar eclipse.

    The moon's shadow, a quarter million miles long, will first touch down slightly west of Hawaii, and then sweep eastward at speeds reaching 5,000 miles per hour.  The dense umbra, less than 200 miles wide, will pass over the tip of Baja California and then across Mexico City.  Finally, the shadow cone will dart back into space from the rain forests of Brazil.

    Alamogordo will only be grazed by the hazy edge of the shadow, the penumbra.  We will see a partial eclipse.  First contact of the moon with the sun will be shortly after 11:30 a.m. MDT.  Mid-eclipse should occur at 34 seconds past 1:01 p.m. MDT.  The sun will be almost directly overhead, 79 degrees above the southern horizon.

    But don't expect anything dramatic.  In fact, although the moon will block almost 68 percent of the sun, the remaining 32 percent is still dazzingly bright.  Many people will go about their business Thursday without noticing a thing.

    Sorry, they'll be no darkness at noon in Alamogordo, and the chickens won't come in to roost.  If you are alert, however, the day will get noticeably darker, slightly cooler, and the sunlight will take on an eerie cast.  Ordinary shadows will appear unnatural, shadows of fingers may have birdlike claws.

    There is only one safe method for looking directly at the sun.  Look through a No. 14 arc-welder's filter.  Be sure to use a No. 14.  Do not risk permanent retina burns with anything else!

    The best way to view this partial eclipse is by projecting the sun's image with a pin-hole telescope.  Take a cardboard box about 12 by 18 inches and cut off the top flaps.  In the center of one end of the box, cut out a two-inch square hole.  Tape a piece of aluminum foil securely over this hole and pierce the foil with a pin or needle.

    Cover the inside of the opposite end of the box with white paper.

    To use this device, stand with your BACK to the sun.  Hold the box slightly over your head with the aluminum side pointed up toward the sun.  Tilt the box until the sunlight falls through the pinhole and onto the white paper.  Do NOT look directly through the pinhole!  Start observing about noon and check developments every 15 minutes or so.

    For the best view in town, drop by the observatory on the Buena Vista school campus.  The Alamogordo Amateur Astronomers will be hosting a public viewing using the 12 1/2 inch reflecting telescope properly fitted with a solar filter.  The dome will open at 11:30 a.m.

    It's too late for plane tickets to Hawaii, and the next total eclipse in the United States isn't until 2017.  But watch this space!  A fascinating annular solar eclipse will pass near Alamogordo in the spring of 1994.

    You won't want to miss it!




Words! Mere Words! Was there anything so real as words? - Dorian Gray