Nocturne is a large black hole located on the border between Aylathiya and Florathel. Its four companion stars and one dozen frigid planets have long been disunited. Nations from across Cosmoria have laid claim to Nocturne's untamed system. When Sagittarium briefly united the endless realms around Nocturne, it was a terrifying empire unmatched by any other. As Sagittarium fell, its client worlds have slowly been taken from it. Currently, there are five major nations that reside under Nocturne's gaze. The immense megastructure of Aubade tirelessly harvests energy from the system's center.
Below is a list of worlds that orbit Nocturne.
Stars
Dorok (Elegy)
Finale
Oratorio
Requiem
Planets
Adagio
Type - Ice World
Native Species - None
Adagio is a small icy world whose surface has adopted a characteristic deep red color due to ferrous impurities. The frozen remains of billions of creatures jut out of the ice. Intelligent species from every era can be found on the world. No artificial structures or materials have been found in the ice, including the equipment needed to reach this remote world. Numerous expeditions to Adagio have revealed that the corpses stretch deep into the planet's mantle. The deeper the fossils, the more marred they are, suggesting that Ma'eau is the cause of Adagio's strange properties. Due to the high levels of phosphorous concentrated on Adagio, in addition to readily-available nitrogen compounds, a number of mining operations call the rogue planet home. Adagio has one moon, Divertimento. The moon is a typical airless world of a little more than a fourth of Adagio's mass. The moon hosts thousands of red-tinted geoglyphs all pointing towards Adagio. To date, over six thousand spacesuit-clad Carlean bodies have been discovered near the glyphs. It is unclear how the Carleans ventured to the planet, however, unusual igneous formations suggest the use of Thaumaturgy. The glyphs, while crude, are usually depictions of Carlean faces with pained expressions, some of which have been scribbled out. Drawings of what seem to be clouds interlaced with gears make up a substantial minority. It is unclear why there is no text anywhere on the planet. There are no settlements currently on Divertimento, but a handful of relatively recent abandoned military bases dot its surface.
Moons - Divertimento
Berceuse
Type - Terrestrial Planet
Native Species - None
Berceuse is a barren world whose only atmosphere is a cloak of radon gas produced in large quantities by the planet's remarkably radioactive mantle. There are bacteria that thrive in the core that create large tree-like structures which take advantage of the mantle's heat. Since the planet is home to a great deal of radioactive material, it was highly sought after for much of history before cheap fusion reactors became common. Since only the largest of craft can bare the load of a fusion reactor, however, the planet's strange supply of elements is a major source of income for the planet's mostly Un'oit inhabitants.
Moons - None
Courante
Type - Terrestrial Planet
Native Species - None
Courante is, on average, the most distant of Nocturne's satellites. Its sister worlds are hardly visible in the perpetual night sky. Courante's north pole points toward Nocturne's four stellar companions. These four stars dance in the northern hemisphere while the southern hemisphere points towards Aylathiya's orange clouds. Due to its cool temperatures, Courante is home to heat-sensitive industry, in particular computing. The planet's millennia-spanning freeze-thaw cycles has encased ancient settlements in neon ice. Courante has the highest concentration of noble gases in Cosmoria, including a light but dense atmosphere of nearly-liquified helium. It is difficult to move about on Courante because of this.
Moons - Allemende
Etude
Type - Ice Giant
Native Species - None
Etude is an ice giant that possesses a faint ring system and seven moons of varying composition. It has the highest Un'oit population outside of their home system of Oratorio. Despite its somewhat isolated position, three of its moons have populations in the tens of billions thanks to large subsurface oceans created by tidal heating. This heating is a relatively recent phenomenon meaning the system has no native life to speak of.
Moons - Canon, Waltz, Rondo, Sonatina, Intermezzo, Fantasia, Serenade
Fugue
Type - Ice Shell
Native Species - None
Fugue is an ice shell world currently under the control of Sagittarium.
Moons - Concerto
Introit
Type - Nitrogen Ocean
Native Species - None
Introit has a very high population despite its small size and frigid temperatures. Transparent oceans of liquid nitrogen dominate the surface. Facilities containing over four hundred billion Thalians dominate the planet's economy. Confined to a virtual existence, the computational demand of keeping them on Introit is immense. The nitrogen seas serve well to keep computation cheap and the facilities cool.
Moons - Minuet, Operetta
Jezreel
Type - Chthonian World
Native Species - None
Jezreel (Un'oit: Rhapsody) is a marine world that was once the core of a somewhat large gas giant. After many close passes to Finale, its atmosphere was slowly ripped away. What remained was a metal-rich and dense world. For most of history, technology was not advanced enough to leave its surface, meaning that venturing to this world was incredibly dangerous. The Vaplein Republic invested into terraforming the world as they exported teratons of its material.
Moons - None
Overture
Type - Terrestrial World
Native Species - None
Overture is a terrestrial world in Sagittarium's domain. With a long history of changing hands, Overture has only recently become firmly Sagittarian.
Moons - Ballade
Sonata
Type - Ammonia Marine World
Native Species - None
Sonata is a contentiously held world, one of the few planets on which interstellar powers share a border. Sagittarium claims the Human cities while the United Nations of Florathel has a peace-keeping force occupy its seas and marine cities.
Moons - Sarabande, Lied
Thalia
Type - Aquatic Marine World
Native Species - None
Thalia (Un'oit: Aria) is a marine world whose surface is over three-fourths water. The capital and most populous world of Sagittarium, Thalia hosts about as many people as the rest of Nocturne. For the past 10,000 years, clear images of its surface have been impossible. A cloak of space habitats, a dense network of orbital rings, and the heat from immense radiators make proper imaging difficult. Thalia is known for its hazy appearance despite having clear conditions on the surface. Thalia is a center of Human colonization of Nocturne. While many of its asteroid moons have long since been destroyed, its ring system has remained in place. Thalia's one major moon of Descort is home to over fifty billion.
Despite being cloaked in eternal darkness, Thalia's Mnemosyne maintains habitable temperatures. Mnemosyne, taking the place of Thalia's core, is a Generatrix that converts Nocturne's gravity waves into heat. This heat, transferred to the surface via mantle convection, is one of the great feats of Sagittarian engineering. Before this impressive project, Thalia's orbital rings doubled as artificial suns. The rings still shine light onto Thalia's surface, but they supply a fraction of the heat they did in the past.
Moons - Tagelied, Reverie, Descort
Megastructures - Mnemosyne