(Be sure to click on the image for the enlarged version)
And Mercury is an unusual sight, even if the moon weren't so close by*. Most folks will never glimpse it -- not knowingly anyway. Being closer to the sun than Earth, it can only appear at sunrise or sunset, like Venus does, but it's so much closer to the sun that it's usually much harder to spot. It needs to be well out to the side, as seen from Earth, or it's overwhelmed in the sun's glare. Also, if its path around the sun - the ecliptic - is parallel to Earth's horizon, then it will rise at the same time as the sun and again the sky is too light. The best viewing is in the early spring or early autumn, when the ecliptic is more vertical to our horizon. This allows Mercury to rise higher before sunrise, or set later after sunset, when the sky is slightly dimmer, like so:
t also happens that Mercury is most visible when it's on the opposite side of the sun from Earth, even though it's farther away then. Otherwise, even though it's closer, it presents mostly its dark side to the world -- much like the moon in the photo, or a Goth chick.
* "Close by," of course, as viewed from Earth. The planet was actually 500 times farther away than the moon was.