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best chance to see shadows cast by Venus once the moon leaves the evening sky, starting the second week of May.
• So Venus is about at its brightest in the evening sky. Yet - in what seems like a paradox - a telescope would reveal Venus now as a waning crescent. It looks like a tiny, featureless crescent moon. Because the orbit of Venus lies inside of Earth's orbit, Venus goes through phases, much like our moon. Surprisingly, Venus' disk appears only 28% illuminated right now, as seen from Earth. Venus appears at its brightest when it's about one-quarter illuminated. How can it be shining at or near peak brightness when we're seeing only a

portion of its lighted hemisphere?
• The answer is that - when Venus appears full as seen from Earth - it's always much farther away, on the far side of the sun from us. That's the only place it can be in order for its fully lighted disk to be facing our way. Full Venus = more distant Venus = fainter Venus overall.
• Now Venus is on the same side of the sun as Earth. It will go between us and the sun on June 5-6, 2012. So a portion of the day side of Venus is turned away from us, and we see a crescent Venus. Yet Venus on the same side of the sun as us, and therefore closer. A telescope would reveal the crescent, but it would also show the crescent as very large. Thus Venus is brightest now.
• Last transit of Venus in 21st century will happen in June 2012
• By the way, in the weeks ahead, Venus will be coming closer still to Earth, but it will be showing us less and less of its lighted hemisphere (day side) as it prepares to pass between us and the sun.
• Late April and early May present Venus' maximum brilliance! Watch for Venus as a dazzling light in the west after sunset.