Yesterday at 4:40AM east time, Nasa's Messenger (MErcury Surface, Space ENvironment, GEochemistry and Ranging spacecraft) flew by just 125 miles over the surface of Mercury, the closest planet to the Sun and the smallest in the Solar System. This is the first time in history that the whole planet is going to be photographed in its entirety by an Earthling probe, with amazing resolution and ultra-crisp detail.
The first time Mercury was photographed up close and personal was in the Mariner 10 mission. Mariner was only able to take pictures of one hemisphere during its flybys, and its camera had a very low resolution: It could only capture details 0.99 miles across. Messenger's wide angle and narrow angle cameras, on the other side, have a resolution of 59 feet across, and is going to be able to take pictures of the fully-lit planet. All while trying not get fried up by the sun thanks to its rotatable solar panels—which balance temperature and power generation—as well as its multilayered insulation. [NASA]