Mercury Probes

Mercury Probes gathers the small number of space probes that have made close observations of Mercury, the least explored of the inner planets because of the high velocity and difficult maneuvering its proximity to the Sun demands of any visiting spacecraft. As of the mid-2020s only three missions had reached Mercury: Mariner 10, which returned the first close-up images and data during a series of flybys; MESSENGER, which made three flybys before becoming the first spacecraft to enter orbit around the planet; and the joint ESA-JAXA BepiColombo mission, which made six flybys of Mercury ahead of its planned delivery of two orbiting probes. MESSENGER and BepiColombo were designed to gather complementary data addressing questions Mariner 10's earlier flybys first raised.