At the northern end, we see the crater rim and ridges inside and below that rim. A channel set is entering from the west and passing through a notch in a ridge.
At the bottom of the crater we see a strange (impact?) spot and an object what looks like a flying saucer.
Is it just an optical illusion or HIRISE has captured a UFO that crashed into the crater wall?
Link Image: http://hirise.lpl.arizona.edu/ESP_044388_2160