01 · terrestrial

Mercury

A cratered iron world with almost no sky. The terminator is a hard line — there is nothing to scatter the light.

Distance from Sol

57.9 m km

Surface gravity

3.70 m/s²

Day length

58.6 earth d

Mean temperature

167 °C

Orbital period

88 days

Atmosphere

Essentially vacuum. A tenuous exosphere of sodium, potassium, and calcium is blasted off the surface by the solar wind. No weather. No scatter. Shadows fall like knives.

Notes

Caloris Basin spans 1,550 km — an impact so violent it wrinkled the crust on the far side. A Mercurian day lasts two years of its own clock. Surface temperature swings 600°C from noon to night.

Illustrative scale · orbital distances compressed. Not an ephemeris.