Mercury-crossing asteroid

A Mercury crosser is an asteroid whose orbit crosses that of Mercury. The Mercury crossers proper have aphelia outside Mercury's (0.4667 AU) and perihelia inside Mercury's (0.3075 AU), whereas those listed here as outer grazers have perihelia within Mercury's aphelion but not within its perihelion. All have semi-major axes larger than Mercury's, and hence there are no known inner grazers.

Mercury crossers proper have aphelia outside Mercury's (0.4667 AU) and perihelia inside Mercury's (0.3075 AU). As of 26 January 2018^[update], there are exactly 300 Mercury crossers known. (Most values have been rounded to three decimals.)

All Mercury grazers have semi-major axes larger than Mercury's (0.3871 AU), and hence are outer grazers, i.e. have perihelia within Mercury's aphelion (0.4667 AU) but not within its perihelion (0.3075 AU). As of February 2016^[update], there are 561 Mercury grazers known. (Values have been rounded to three decimals.)

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