Venus reaches its greatest illuminated extent or greatest brilliancy in the evening sky on December 6, 2013. That means the planet’s daytime side is covering more square area of sky than at any other time during Venus’ present apparition as the “evening star.” And it means that Venus is brighter now than at any other time during this evening apparition.
You might think Venus appears brightest when we see its disk as most fully illuminated from Earth. Not so. If you were to observe Venus with the telescope today, you’d see that Venus’s disk is only a touch more than one-quarter illuminated by sunshine. A full Venus is always on the far side of the sun from us, so its disk size at full phase is always small. It’s only when we see Venus as a crescent that this world comes close enough to us to exhibit its greatest illuminated extent, at which time its daytime side covers the greatest area of sky.
Venus entered the evening sky on March 28, 2013 and will leave it on January 11, 2014. Where will it go? It’ll pass more or less between us and the sun on January 11. Astronomers call that an inferior conjunction of Venus.
For the full article: Tonight Sky