Do you know about Mercury

Mercury is the innermost and smallest planet in the solar system, orbiting the Sun once every 88 days. Mercury is bright when viewed from Earth, ranging from -2.0 to 5.5 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun is only 28.3°. It can only be seen in morning or evening twilight. Comparatively little is known about it; the first of two spacecraft to visit Mercury was Mariner 10, which mapped only about 45% of the planet’s surface from 1974 to 1975. The second is the MESSENGER spacecraft, which mapped another 30% during its flyby of January 14, 2008. MESSENGER will make two more passes by Mercury, followed by orbital insertion in 2011, and will then survey and map the entire planet.Detail