Although we're often told not to shoot the messenger, the Messenger is certainly shooting up outer space. The spacecraft blazed past Mercury in mid-January, and took some rather remarkable snapshots of the tiny grey planet closest to the sun.

The most impressive of those pictures has been dubbed "The Spider," and features a massive geological formation that has dazzled scientists. Many believe the subject of Messenger's photographs -- a giant, central depression surrounded by over a hundred thin trenches zig-zagging each way outwards -- is something very new and very exciting in recent exploration of the solar system. (Source: nytimes.com)

Messenger's principal investigator, Sean C. Solomon, is particularly excited about the finding. "Messenger has sent back data near perfectly, and some of it confirms earlier understandings, and some of it tells us something brand-new," he stated. "The Spider is definitely in the category of something we never imagined we'd find." (Source: latimes.com)

In addition to the massive, arachnid-like depression, scientists are also raving about a series of ancient volcanoes scattered across Mercury's landscape. Experts often compare Mercury with the moon, given their comparable sizes. It's safe to say nothing like this has ever been seen on that rock where Neil Armstrong once treaded.

Also unlike the moon, Mercury's surface includes massive, teeth-rattling cliffs and lines that indicate fault activity within its crust. Solomon, who works with the Carnegie Institution of Washington, is still shaking his head at the findings. "It was not the planet we expected...It's a very dynamic planet with an awful lot going on."

Messenger will be spending quite a bit more time getting acquainted with its new friend Mercury. The spacecraft will wrap around the tiny planet two more times before remaining in orbit sometime in 2011.