was once the economic center of the Sol System
, but today most of its people are refugees. The Scorching of Mercury has left the planet an arid husk of its former glory. A small amount of factories and mines are still operational, buried deep enough into the crust of Mercury to avoid the extreme outside temperatures. The workers of these factories spend their entire life underground now that the surface has become so hostile.
The defense of Mercury is orchestrated by the Interplanetary Solar Defence Council
, which is headed from the satelite station Caduceus
with a surface-side presence in the migratory military base Penumbra
. A small group of civilians tail Penumbra, either to support or to seek shelter with them.
The sun has always had a profound impact on Mercury, in no small part due to the resonances of its orbit. The planet spins around itself one and a half times faster than it orbits the sun. Not only does this make the sun appear to move backwards through to the sky, it makes a Mercurian day last twice as long as a Mercurian year.
It takes 176 days
for Mercury to complete one solar cycle, so each phase of the day is roughly analogous to a season. The transitional dawn and dusk phases last around 12 days, while the diurnal and nocturnal phases last for an average of 76 days.
Even before the Scorching of Mercury
, Mercury's seasons would lead to extreme peaks of heat and cold. With the loss of atmosphere the differences have risen to extremes. The diurnal phase gets hot enough to boil off any liquids on the surface, an almost intolerable heat. Meanwhile the night, without any atmosphere to retain the heat and keep it from simply radiating back out into space, the nocturnal phase gets far below freezing.
Phases of the Solar Cycle
| Dawn Phase
| Diurnal Phase
| Dusk Phase
| Nocturnal Phase
For a more indepth visualization see: A Day in the Caloris Basin
Visit Mercury by Annie Stein
Planet of the Still Sun
The traditional Mercurian calendar begins when the Sun stops over Hun Kal
at the perihelion of Mercury's orbit. This event, known as the Still Sun
, occurs when the sun stops in the sky, then reverses and moves forward for a few days, before ultimately stopping again and resuming it's backwards motion.
Mercury's tourism boomed as the planet neared perihelion. Many came to partake in the festivities and observe the phenomena, sometimes even returning to get another perspective. At Hun Kal, the sun reverses during high noon of the Still Sun. Cities along the western edge of the terminator experienced a double dawn, while the eastern edge observed a double dusk.
This oddity of Mercury's solar cycle occurs because the speed of Mercury's orbit is not consistent. When the orbit is at perihelion, the closest to the Sun itself, the orbital speed picks up enough that the sun is finally moving faster through the sky than Mercury is spinning on it's own axis.
Those who live on the surface of Mercury after the Scorching survive by migrating along the terminator
. The slow solar cycle and the small size of the planet makes it viable to travel to always remain in the twilight. The terminator slowly circles the planet at at around 3.6 km/h or 2.2 mph.
Most nomads, and the migratory military base Penumbra
, travel to the edge of dusk, and stay there until dawn. This usually allows them to stay still for about a week before they resume moving.
Others chose to constantly travel, only pausing to sleep and then get moving again.
The Mercurians were not the earliest spacefarers, but they took to it like no others. They rapidly expanded across the Sol System, led by explorers and followed by merchants. At the largest, their merchant empire stretched all the way from Mercury, out to Pluto in the Kuiper Belt. What started as trading outposts eventually became colonies as the Mercurian Imperial project began in the Late Spacefaring era. Mercurian nations sprung up on moons and planets across the Solar system.
Resources, and thus wealth, flowed out from the planets and colonies they were extracted from back to the imperial core. Although some of the surplus of this rich trade was captured by enterpreneurial Mercurians who established plantations and companies abroad, the majority of the wealth was concentrated among a small elite. The colonizers were loathe to give up any of the creature comforts of their home, though, and Mercury became associated with opulence as luxury goods found their way first to the colonies, then to the colonized populace.
Towards the end of the Imperial period, the complexity of the colonial networks reached a zenith. Each colony functioned as a node in a larger web of goods, and some products passed through multiple colonies before reaching Mercury. The revolts that ended the period were thus accompanied by an extended period of economic upheaval as colony after colony crashed out of this web, and some products were never produced again, while others eventually returned as a result of more equitable trade.
The colonial revolts are not forgotten. Efforts towards reparations were started not long after the end of the empire, but the hardships the Mercurian people have suffered since the start of the Scorching caused many of these programs to be halted or cancelled entirely. Some criticize the fact that Mercurian elite, the chief benefactors of the Sol-wide system of exploitation, still maintain a substantial amount of their wealth in the form of off-Mercury assets and investments. These voices are increasingly quiet, however, as public sympathy towards Mercury mounts.