Explore is a way to discover the most interesting photos on Flickr. It shows the top 500 most interesting photos of every day. Each photo competes in the day it is uploaded, and the top list changes over time according to the views, comments, etc. of the photo. These 500 photos are selected by computers based on measurable factors.
While checking Scout today, I've realized that two new photos hit the Explore recently, and with these, I now have 10: