NEW YORK — The first batch of hundreds of photos taken in orbit of Mercury show numerous battle scars on the tiny planet. They are from space rocks regularly pelting Mercury at high speeds, scientists said.

NASA's Messenger spacecraft, the first to orbit Mercury, reveals a pock-marked planet full of craters from pieces of asteroids and comets. Mission chief scientist Sean Solomon said that what is surprising to scientists so far is that there are more secondary craters than expected. Those are craters created by the falling soil kicked up from space rock collisions.

Solomon said the craters look different from those on the moon because the space rocks are moving faster and hit Mercury harder.