|June 8, 2009||Permalink|
The planet Mercury is the smallest of the inner planets (4,880 km/3,032 mi in diameter), and the closest to the Sun (58 million km/36 million mi - or 3.2 light minutes). It was visited by the Mariner 10 spacecraft twice in the 1970s, and about 45% of the surface was mapped. On August 3rd, 2004, NASA launched a new mission to Mercury, the MErcury Surface, Space ENvironment, GEochemistry and Ranging probe (or MESSENGER). MESSENGER is now in the last stages of multiple gravity-assist flybys of Earth, Venus and Mercury, en route to an insertion into orbit around Mercury in March of 2011. In just two flyby encounters, MESSENGER has already greatly increased our knowledge about Mercury's surface features. As you look at Mercury in the new images below, keep in mind that it has minimal atmosphere, gravity about 1/3 of Earth's, and surface temperatures ranging from -183 C (-297 F) in some polar craters to 427 C (801 F) at high noon (Mercury's solar day lasting 176 Earth days). (20 photos total)
As NASA's MESSENGER spacecraft receded from Mercury after making its closest approach on January 14, 2008, it recorded several mosaics covering part of the planet not previously seen by spacecraft. The color image shown here was generated by combining the mosaics taken through three filters (infrared, far red and violet). These three images were placed in the red, green, and blue channels, respectively, to create the visualization presented here, creating a false-color image that accentuates the subtle color differences on Mercury's surface. (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)
To see the entire entry, with all photographs, click here.
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