The planet Venus is the first “star” to come out after sunset throughout September 2013, and indeed through the end of this year. Look in the western twilight dusk to behold this most dazzling of worlds. Just be sure to catch Venus soon after sundown, for this planet will follow the sun beneath the horizon by nightfall or early evening. Watching Venus over the coming days – from now through at least September 8 – is well worth it. This planet is near a bright star now, and another planet (Saturn). Plus the moon will soon return to the west after sunset to stage a dramatic pairing with Venus on September 8. Click here for more about the moon-Venus pairing on September 8. From the right spots in South America on that day, you can actually watch the moon occult – cover over – Venus.
Venus ranks as the third-brightest celestial body, after the sun and moon. On September 4, 2013, if your sky is clear, and your timing is just right, you should be able to spot Spica, the constellation Virgo’s brightest star, quite close to Venus. Spica and Venus are closest together on September 4 and September 5. If you can’t see Spica with your unaided eye, yet have binoculars, aim them at Venus to find Virgo’s brightest star.
Spica is a perfect example of a what astronomers called a first-magnitude star. In other words, it’s one of the brightest stars in our sky. But Venus is so much brighter! Venus beams about 100 times more brightly than any star of first-magnitude brightness.
Day by day, Spica is sinking into the glow of sunset while Venus is climbing away from it. Thus Spica will soon disappear in the sun’s glare, while Venus will remain in the evening sky for some months to come.
What about Saturn? The planets of the rings has been near Spica on our sky’s dome for a couple of years now, so, if Spica is visible, you can see Saturn, too. Look for Saturn along the ecliptic, or path the sun travels across our sky. Venus and Saturn will occupy the same binocular field of view from about September 15 to September 21. The actual conjunction of Venus and Saturn (when they have the same right ascension on the sky’s dome) comes on the evening of September 19.
Bottom line: As seen from around the world, Venus and the star Spica will appear near each other in the west after sunset in early September, 2013. They are closest together on September 4 and 5. Be sure to look shortly after the sun goes down. Use binoculars, if you have them, to scan for Spica in the twilight sky – near Venus! Then, as the dark darkens, you should be able to pick out Spica with your eye. Be sure to look in the west on September 8, 2013, when the moon will be dramatically close to Venus. Then keep watching. You’ll see the planet Venus swings by the star Spica as it travels onward toward the planet Saturn.