Darkening Days

While sunlight wanes, the moon waxes with winter’s stars

The sun sets its earliest of the year on Sunday, December 7, at 4:43:38, two weeks before winter solstice, the shortest day of the year. While we gain a few seconds of sunlight at day’s end, we lose roughly 45 seconds of light in the morning each day, a result of Earth’s egg-shaped orbit around the sun.

Evening twilight reveals Venus and Jupiter low in the southwest. At week’s end they are still within five degrees of one another, Venus brighter and higher in the sky. But the two planets are fast separating, adding almost a degree between them each night.

The waxing moon reaches first quarter Friday, December 5, appearing high in the south at sunset and arching westward before setting after midnight. As the moon grows, it appears more than 10 degrees farther to the east and sets more than an hour later each night.

Wednesday evening the moon shines just a few degrees west of the stars of the Pleiades cluster, inching closer hour by hour. From 3am to 4am Thursday morning, the moon eclipses one star after another, finally emerging to the east of the cluster at 5am and then setting an hour later.

In Greek mythology, the Pleiades were the seven sisters Maia, Electra, Taygete, Alcyone, Celaeno, Sterope and Merope. Born to the giant Atlas and Pleione, they served the goddess Artemis. By one legend, they achieved their place among the stars after Orion, overcome by their beauty, pursued them for seven years. Finally, Zeus answered their pleas and changed them into doves, setting them among the heavens. Later, angered that the great hunter had not only caused the loss of her attendants but also had slighted her own advances, Artemis set the great scorpion upon Orion.