Mercury
| Mercury | |
|---|---|
 Mars as seen by MESSENGER, 2008 | |
| Star, Position | Sol, I |
| Diameter | 4,879 km |
| Length of day | 58.646 earth days |
| Length of year | 87.97 earth days |
| Surface gravity | 0.38 g |
| Mean temperature | 100−700 K |
| Adjective | Mercurian |
| Population | 431,000 |
| Government | United Mercurian Confederation |
Mercury is the smallest planet in the Sol system and the closest to Sol. It was first settled in 2085 by the Hermes colonial venture. Its goal was to establish a permanent human presence on Mercury, with humans living in dome cities in craters located in the permanent twilight zone of Mercury, which is an area where the Sun never fully rises or sets, allowing for more manageable temperatures as well as permanent solar power.