More than Meets the Eye

Sometimes the light we see is only half the story

The waxing moon rises Thursday at 5:25, two hours before sunset. By Saturday, the full moon rises in the southeast as the sun sets in the northwest around 7:30.

April’s full moon bears many names. As the great plains turned green, the Sioux called this the Grass Moon. Algonquian tribes of the Northeast called this the Pink Moon, as the blooming wild phlox transformed the color of the landscape. Tribes along the Atlantic Coast called this the Fish Moon for the annual migration of shad swimming upstream to spawn.

Shining a few degrees above the full moon is Spica, the blue-white beacon of Virgo. In truth, Spica is two stars less than one-third the distance from Mercury to the sun and orbiting one another in a frenzied figure eight every four days. But from 260 light years away, Spica is a first-magnitude star shining more than two thousand times brighter than the sun.

The waning gibbous moon washes out all but the brightest “shooting stars” of this year’s Lyrid Meteor Shower, which peaks midnight Tuesday/Wednesday. Still, keep an eye toward the celestial harp, marked by its bright summer star Vega.

The Moon joins another summer star Tuesday and Wednesday, the red super-giant Antares of Scorpius. Appearing at first-magnitude and ranked the 15th brightest star, Antares is much more. Much of Antares’ light, coming from 600 light years away, is in the infra-red spectrum. With 21st-century optics like Chandra Orbiting Observatory, astronomers have revealed that Antares shines 60,000 times brighter than the sun and is three-fourths the size of Jupiter’s orbit around the sun.

Tidelog®

Illustration: © Copyright 1925 M.C. Escher/Cordon Art-Baarn-Holland; Graphics: © Copyright 2007 Pacific Publishers. Reprinted by permission from the Tidelog graphic almanac. Bound copies of the annual Tidelog for Chesapeake Bay are $14.95 ppd. from Pacific Publishers, Box 480, Bolinas, CA 94924. Phone 415-868-2909. Weather affects tides. This information is believed to be reliable but no guarantee of accuracy is made by Bay Weekly or Pacific Publishers. The actual layout of Tidelog differs from that used in Bay Weekly. Tidelog graphics are repositioned to reflect Bay Weekly’s distribution cycle.Tides are based on National Oceanic and Atmospheric Administration and are positioned to coincide with high and low tides of Tidelog.