Exploring the Solar System

Exploring Mercury and Venus

What has the MESSENGER achieved?

MESSENGER has made significant discoveries. Starting with its first flyby of Mercury in January 2008, it took pictures of a side of the planet that has never been seen by human eyes. Scientists had thought, based on Mariner 10 data gathered in the 1970s, that Mercury was very similar to the Moon, but MESSENGER has shown that Mercury has a unique and active geological history. The surface has long fault lines, a remarkable spider-like formation in the center of its Caloris basin, and also has significant pressure within its magnetosphere. Perhaps most surprisingly, MESSENGER has detected billions of tons of water ice underground at Mercury’s polar regions.


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