March 17, 2003
Antoniadi Ridge, over 450 kilometers long, runs along the right side of this image. The ridge transects a large crater (80-km in diameter) and in turn appears to be interrupted by an irregular rimless depression on the floor of the crater. This ridge also crosses smooth plains to the north and intercrater plains to the south of the large crater. This image (FDS 27325) was acquired during the spacecraft's first encounter with Mercury.