Mercury after MESSENGER’s first flyby: a cratered, sunlit disk dissolving into night.
MESSENGER flyby mosaic · NASA / JHUAPL / CIWHigh-resolution mosaic of Mercury as seen by NASA’s MESSENGER spacecraft departing after Flyby 1. NASA / Johns Hopkins University Applied Physics Laboratory / Carnegie Institution of Washington. SVS 30340.

MESSENGER

Nearest the Sun.

Fast in the sky. Slow on itself.

A world of iron, glare, and permanent shadow.

Rate

−0°42′ / day

minimum elongation

Mercury’s recorded daily motion.

Interval

69 days later

evening rise

naked-eye wanderer · iron world · polar shadow · resonance · return

The walk