It is the closest planet to the Sun , and second smallest planet in the solar system . It is even smaller than Jupiter's moon Ganymede and Saturn's moon Titan . If an explorer were to step onto the surface of Mercury, he would discover a world resembling lunar terrain. Mercury's rolling, dust-covered hills have been eroded from the constant bombardment of meteorites . Fault-cliffs rise for several kilometers in height and extend for hundreds of kilometers.
Craters dot the surface.
As the explorer gazes out into space, he might see two bright stars. One appearing as cream colored Venus and the other as blue colored Earth . At maximum elongation it is only 28 degrees from the Sun as seen from Earth. Because of this, it can only be viewed during twilight or daylight hours, and the view is through a long path of Earth's atmosphere. During the 1880's, Giovanni Schiaparelli drew a sketch showing faint features on Mercury.