Bill & Ted's Excellent Astro-Picture Pages
Mercury and Venus
The planets Mercury and Venus orbit closer to the Sun as compared to Earth. Thus you will only see Venus and Mercury after sunset or before sunrise. That is why Venus is often called the Morning Star or Evening Star. It is very bright and easy to see just after sunset or it is the last star to fade away in the sunrise.
Mercury is very small. The best way to illustrate is to show Mercury when it is closest. That is when Mercury is between Earth and the Sun. The event is known as a Transit and clearly shows just how tiny Mercury is in the sky.
Transit of Mercury 1999
Mercury is the tiny little dot the edge of the solar disk.
Venus is much larger by comparison. Yet Venus is shrouded in clouds appears a very bright white color in the eyepiece. Because the orbit of Venus is inside that of the Earth, Venus goes through phases ranging from a crescent to a near full disk. Transits of Venus are rarer than transits of Mercury however they are easier to see. The small dot of Venus against the Sun can be seen with just a filter. A telescope is required to see the disk of Mercury.
Canon Digital - Coronado Ha 40mm telescope - 2004
Venus in crescent phase
Venus in Gibbous phase
Celestron 5" - Canon Digital EOS - 2x barlow