WEDNESDAY, AUGUST 3 As the Moon makes its monthly journey eastward along the ecliptic, it passes by a handful of bright stars, and one of the brightest is lst-magnitude Spica, in Virgo. Indeed, only Aldebaran, in Taurus, outshines it - and only by 0.1 magnitude. However, Spica is offset just 2° below that solar system superhighway known as the ecliptic, compared with 51/2° for the Taurus luminary. This evening the waxing lunar crescent is positioned 3° above Spica. This pairing is notable because it's the best one remaining in this year's dusk series. The twosome combines once again on the 30th, but on that occasion they'll be farther apart (41/2°) and closer to the horizon. By the time the Moon revisits Spica in late September, the star will be just 20° from the Sun and lost in twilight's glare. You'll have to wait until November to see the Moon and Spica together again when the star re-emerges at dawn.
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