Mercury is the smallest planet in the Solar System. Its radius is a mere 2,439.7 km. It is so small that the moons of other planets such as Ganymede and Titan are larger than Mercury. Despite being the smallest planet in the Solar System, Mercury is denser than any of the larger gas giants such as Neptune, Uranus, Jupiter or Saturn. This is because Mercury has a solid surface while the other planets are usually made up of different gasses. [...]

Texts and descriptions are fine and dandy, but to see planet Mercury for what it is is another thing altogether. Enjoy these pictures of Mercury.    

Mass (kg): 3.3 x 1023 Diameter (km): 4879.4 Mean density (kg/m3): 5420 Escape velocity (m/s): 4300 Average distance from Sun: 0.387 AU (57,909,175 km) Rotation period (length of day in Earth days): 58.65 Revolution period (length of year in Earth days): 87.97 Obliquity (tilt of axis degrees): 0 Orbit inclination (degrees): 7 Orbit eccentricity (deviation from circular): 0.206 Mean surface temperature (K): 452 Maximum surface temperature (K): 700 Minimum surface temperature (K): 100 Visual geometric albedo (reflectivity): 0.12 Largest known [...]

1. Mercury is the eighth largest planet (or second smallest) in the Solar System. 2. The orbital speed of Mercury is 47.8 km/sec 3. Mercury has no atmosphere and no known satellites, perhaps because of its proximity to the Sun. 4. The diameter of Planet Mercury is 4,878 km 5. The only visit to Mercury was a flyby made by the Mariner 10 spacecraft in 1974. 6. Mercury, often identified with the Greek god, Hermes, is the messenger of the [...]