NASA's Messenger Spacecraft Releases First Close-Ups of Mercury

NASA's Messenger spacecraft has released its first shots of Mercury -- the first ever taken by a craft in orbit around the innermost planet in our solar system.

The high-res glimpse of the myriad dusty craters on the distant planet is the first tantalizing offering from Messenger, which has sailed into orbit high above the planet’s south pole and reveals Mercury's previously unseen surfaces.

“The entire Messenger team is thrilled that spacecraft and instrument checkout has been proceeding according to plan,” said Sean Solomon, Messenger's principal investigator from the Carnegie Institution of Washington.

“The first images from orbit and the first measurements from Messenger’s other payload instruments are only the opening trickle of the flood of new information that we can expect over the coming year. The orbital exploration of the Solar System’s innermost planet has begun,” he said.

The very first image taken by Messenger from orbit revealed a large rayed crater called Debussy, as well as a smaller crater called Matabei. The bottom portion of the image show Mercury's south pole and includes a region of Mercury's surface not previously seen by spacecraft.

Other pictures released by the space agency show a pock-marked planet remarkably similar to the moon, scarred by the impact of countless asteroids and other space rocks regularly pelting Mercury at high speeds, scientists said.

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.

On March 17, Messenger became the first spacecraft to orbit the planet Mercury. In the course of the $446 million probe's one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet.

The spacecraft is in an tight orbit that brings it within 124 miles of Mercury at the closest point -- and takes it out more than 9,300 miles away at the farthest point.

NASA and the Messenger team will release additional photos over the next few days -- the spacecraft is set to photograph 1,185 images over a three day period, the agency said.

While Messenger is the first mission ever to orbit around Mercury, it is not the first spacecraft to visit the planet. NASA's Mariner 10 spacecraft flew by the planet three times in the mid-1970s.