The moon and the planet Venus rank as the second-brightest and third-brightest celestial bodies to bedeck the heavens after the sun. As soon as dusk gives way to darkness, use dazzling Venus to find the planet Mercury, and then use the bright waxing gibbous moon to find the golden planet Saturn (plus the sparkling blue-white star Spica).
Look first for Venus and Mercury rather low over the west-northwest horizon some 45 to 60 minutes after sunset. That’s because these two worlds will follow the sun beneath the horizon before it gets good and dark. The moon and Saturn, on the other hand, will be out all evening long.
Venus and Mercury will only be about 2o apart – about the width of your little finger at an arm length away. Venus shines about 100 times more brightly than Mercury does, so you may need binoculars to spot Mercury in Venus’s glare. If you live in the Northern Hemisphere, you may also see the nearby Gemini stars, Castor and Pollux.
Both of these planets – Mercury and Venus – circle the sun inside of Earth’s orbit. Mercury is the innermost planet of the solar system whereas Venus is the second planet outward from the sun. Earth, the third planet outward, cirlces the sun sun inside of Mars’ orbit, the fourth planet outward. At present, Mars is extremely hard to see because it sits in the glare of morning dawn.
Bird’s-eye view of inner solar system on June 19, 2013
From either the Northern or Southern Hemisphere, the moon and Saturn stay out till the wee hours of the morning. Saturn, the sixth planet outward from the sun, is the most distant world that you can easily see with the unaided eye. However, you can easily see this planet’s glorious rings through a modest, backyard telescope.
This early evening, you can see three planets at the drop of the hat. Venus points out Mercury at evening dusk, and the moon points out the ringed planet Saturn at nightfall.