• As darkness falls this evening in North America, the rather wide waxing crescent moon appears to the south of the constellation Libra, and to the east of the planets Saturn and Mars. In the Eastern Hemisphere - Europe, Africa, Asia, Australia and new Zealand - tonight's moon will be closer to Mars and Saturn than it is in the Western Hemisphere. Despite the lunar glare, the moon can help you find Libra's brightest stars: Zubenelgenubi and Zubeneschamali. As evening deepens, the planets, moon and these Libra stars descend westward, to sink beneath the southwest horizon during the evening

hours.
• Zubenelgenubi has the star designation "alpha" in the constellation Libra, even though Zubeneschamali is the slightly brighter star. Zubenelgenubi sits almost exactly on the ecliptic - the sun's annual path in front of the background stars. If you could see the stars during the daytime, you'd see the sun and Zubenelgenubi in conjunction on or near November 7 every year.
• The sun goes by Zubenelgenubi once a year, but the moon sweeps by Zubenelgenubi every month. Unlike the sun, the moon can swing anywhere from five degrees (10 moon diameters) north to five degrees south of this star. For the next few years, the moon will pass to the south of (below) Zubenelgenubi.
• Starting on January 7, 2013, the moon will occult - swing in front of - Zubenelgenubi every month until May 14, 2014. After that, the moon will swing north of (above) Zubenelgenubi each month, not to occult this star again until October 8, 2021.