article about the moon... what's up with the North Pole?

[vger]

So this Yahoo article about the Moon's north pole came into my feed today.

http://news.yahoo.com/nasa-hd-moon-map-reveals-lunar-north-pole-100710053.html

These images have me curious. Is this just a trick of light? Am I actually seeing deeper craters at the North pole than the surrounding latitudes?

If so, how did this happen? The impacts at the poles should be far less intense than lower lats, but this mosaic suggests the opposite.

[Kryten]

The mosaic is made up of pictures where the sun is as close to directly overhead as possible. Close to the poles, the sun will barely pass over the horizon at any tine, leading to areas of permanent or semi-permanent shadow, which end up on the mosaic. The shadows are what make them look deeper.