(Continued from page 17)

ter both rise into the sky well before dawn's first light. At mid-northern latitudes, Jupiter rises about four hours before dawn, and Venus about two hours before. They're both high in the sky at dawn.
• Before dawn, look for Aldebaran near Jupiter, and for Castor and Pollux in the vicinity of Venus
• Tomorrow's thin waning crescent moon will rise in the dark hour before dawn, signaling the coming of Mercury and the break of day. If you're up before the glow of dawn starts to obscure the sky, look for the brightest stars in the constellation Gemini the Twins - Castor and Pollux - in the neighborhood of Venus. And look for the ruddy star Aldebaran near Jupiter. We draw in the ecliptic - Earth's orbital plane projected onto the sphere of sky - because the moon and planets are always found near the ecliptic. So you're not looking far to the north or south here. Instead, you're looking along the sun's path across the sky. The constellation Orion is also visible in the predawn sky, to the right of Venus and close to the eastern horizon.
• The constellation Orion and Sirius the Dog Star
• All three morning planets - Venus, Jupiter, Mercury - shine in front of different constellations. Jupiter beams in front of the constellation Taurus. Venus blazes away in front of the constellation Gemini whereas modestly-bright Mercury lights up the constellation Cancer.
• Bottom line: As darkness gives way to dawn on August 15, 2012, dazzling Venus and Jupiter will be easy to see above the moon in the eastern predawn sky. These bright objects can lead you to a fainter one that's much closer to the horizon - the innermost planet Mercury. You will need a clear sky and an unobstructed view toward the east before dawn to see Mercury.
•