The exploration of Mercury has a minor role in the space interests of the world. It is the least explored inner planet.[1] As of 2015, the Mariner 10 and MESSENGER missions have been the only missions that have made close observations of Mercury. MESSENGER made three flybys before entering orbit around Mercury.[2] A third mission to Mercury, BepiColombo, a joint mission between the Japan Aerospace Exploration Agency (JAXA) and the European Space Agency, is to include two probes. MESSENGER and BepiColombo are intended to gather complementary data to help scientists understand many of the mysteries discovered by Mariner 10's flybys.
Compared to other planets, Mercury is difficult to explore. The speed required to reach it is relatively high, and its proximity to the Sun makes it difficult to maneuver a spacecraft into a stable orbit around it.[3] MESSENGER was the first probe to orbit Mercury.
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