Pantheus System

Template:Star SystemThe Pantheus System, also known as EGC-13, AELNIS-1 or RS-8496-928-6-91668-45 is a .990 star system located in the fringes of the Orion Arm in the Milky Way. Pantheus is a binary system, consisting of a 1.26 solar mass F9 spectral class star, known as Pantheus A (Cthnos), and a .67 solar mass K5 spectral class star, known as Pantheus B (Klintriarch). From Sol, Pantheus appears as a magnitude 11.78 star in the constellation of Crater.

Both stars in the system have complicated planetary systems. Cthnos has 11 planets and 20 rounded moons, while Klintriarch has a system of 12 planets and 22 rounded moons. The majority of the system's mass resides in the Cthnoite system as it is orbited by five J-class planets, all of which have masses exceeding that of Jupiter. The Klintriarchian system by comparison is predominantly N-class and I-class planets.

The Pantheus System was first cataloged in early sky surveys of the 21st and 22nd centuries. Interest in the system began when famous human explorer Valentino Arsiza visited in 2345 and documented the system, adding it to his Expansion General Catalogue as EGC-13. When Arsiza later created Arsiza's List of Notable Interstellar Systems, Pantheus was classified as AELNIS-1.

Although Sylvester Arsiza would later discover more unique systems, the Pantheus System remains significant as one of his favorites, and one of the first he put considerable effort into investigating. The system is well known today among local residents of the Confederacy of Humanity. It is now administered as a historic location, offering tours of the system to visitors and drawing in a moderate attendance rate.

Names

The Pantheus (/pɑːnθiːʌs/, pahn-thee-US) System was named by Valentino Arsiza very early on during his exploration of the system. Pantheus is derived from the world Pantheon, as Arsiza believed the plentiful amount of large bodies in the system were analogous to a pantheon of deities. The demonym of Pantheus is Panthian.

The Pantheus System, before it was explored, was assigned designation RS-8496-928-6-91668-45 by SCART in accordance with the Initial Naming System.

The Exploration General Catalogue denotes the Pantheus System as EGC-13, as it was the 13th celestial object that Arsiza considered interesting enough to warrant revisiting in the future. It is generally considered one of the EGCs most famous and popular objects, and is one of the few early EGC objects to be colonized. The Pantheus System is closer to the Solar System than most other early EGC objects, in contrast with objects like Catacylsma which are out of the Milky Way entirely.

The ALENIS (Arsiza's List of Notable Interstellar Systems) Catalouge was created following Arsiza's initial exploration of the Pantheus System. Arsiza felt that a new list had to be created that distinguished thoroughly explored and notable star systems from the the EGC's more inclusive list of deep sky objects and other bodies. As the first system explored thoroughly enough to meet the criteria, the Pantheus System was denoted AELNIS-1.

Discovery and Exploration

Early Exploration

The Pantheus System was first by cataloged by humanity in the Pan-STARRS sky survey during the 21st century. By the mid 2200s century the Pantheus system is known to have been registered by at least one SCART system, but no evidence that it was explored before the 2300s remains.

Valentio Arsiza discovered the Pantheus System on a routine journey to find local stellar systems for his EGC catalogue. He departed the solar system in early 2345 and arrived at Pantheus after several weeks of searching the Orion Arm. Arsiza's interest in the system came as a result of its SCART reading of 21 planets (early SCART registered Liana as a moon rather than a binary partner.), which was among the highest of any system he had yet encountered. The detection of microbial life in Uoros was also attractive to the young Arsiza, who only recently discovered his first unicellular life on Avastion and Thoures.

Location

The closest stellar systems and R-class planets to the Pantheus System.

The Pantheus System is located in the Orion Arm of the Milky Way  galaxy, 1,360.39 ly from Confederacy capital and human homeworld Earth. Pantheus is below the majority of galactic plane, giving bodies in the system a distinctly flat view of the galactic plane.

The closest stars system to Pantheus is the Abbaca Proxima system, at 4.14 ly away. The next nearest star systems are the Biother system (5.21 ly away) and the Biasint System (5.63 ly away), both of which have bodies with multicellular life. The closest R-Class planet to Pantheus is Akkurath, at 3.06 ly away. It is close enough to the system where Cthnos and Klintriarch appear as distinct stars if viewed from its surface.

The Milky Way as it appears from the Pantheus System, surrounded by globular clusters.

The nearest DSO to the system is the planetary nebula Ghost of Jupiter at 514.89 ly away, which appears at magnitude 6.42. Other DSOs prominent in the skies of Pantheus include the Carina Nebula and Fleming 1. Given Pantheus' position relative to the galactic plane, the Milky Way's globular clusters appear densely concentrated around the galactic core. The brightest globular cluster from the Pantheus System is M 62.

The constellation Orion as it appears from the Pantheus System.

Given the Pantheus System's proximity to the Solar System, many prominent stars in the Panthian sky are familiar to Earth natives. Examples include stars in the Carina and Orion constellations.

System Architecture

Orbits of the suns of the Pantheus System. Barycenter shown in teal.

Pantheus is a binary system, with both Cthnos and Klintriarch orbiting a central Barycenter. Both orbits intersect, and Cthnos is the inner of the two orbits, having a pericenter of 139.26 AU and an apocenter of 419.39 AU. Klintriarch's orbit by comparison has a pericenter of 263.67 AU and an apocenter of 794.07 AU. The stars orbit with a 1:1 resonance, with both stars completing an orbit every 20,283 years. Cthnos travels at 952 mph while Klintriarch travels at 1,737 mph.

Both planetary systems have significantly deviant orbital planes. The Cthnoite planetary system is angled 50° relative to the plane of the system, while the Klintriarchian planetary system is angled 230° relative to the plane of the system.

The Pantheus system has no circumbinary planets.

System Bodies

The Pantheus system has a total of 23 planets, 11 of which are around Cthnos and 12 of which are around Klintriarch. The majority of the Panthian planets are gas giants, most of which have moons massive enough to undergo hydrostatic equilibrium, and some large enough to sustain liquid cycles and atmospheres. There are a total of 65 planetary mass objects in the Pantheus System.

Cthnos

Cthnos (/kɪθnoʊs/, KITH-nos), otherwise known as Pantheus A, is a 1.26 solar mass F9 spectral class star and the main body of the Pantheus System. A white class F star, Cthnos is significantly brighter than the sun and the majority of main sequence stars in the universe. Cthnos and the Cthonite system formed 1,002,200,000 ago, and is two million years younger than Klintriarch. Cthnos occupies approximately 65% of the mass of the Pantheus System. The habitable zone of the star extends around 1-2 AU and includes the planet Mauru.

Heaphance

Heaphance's superheated gas envelope glows fiery colors.

The first planet from Cthnos, Heaphance (/hɛfæns/, HEH-fanss) is a hot J-class world over four times the mass of Jupiter. Heaphance is primarily made of water vapor and hydrogen, with a substantial mantel and traces of helium. Despite being only the second most massive of the Cthnoite gas giants, its proximity to Cthnos renders Heaphance the largest planet in the Pantheus System (1.2x the diameter of Jupiter). Heaphance, if cool, would be a dark lavender color, but through thermal radiation it appears red and yellow. The planet is large enough to be seen as a prominent disk at the orbit of Oaven, where it can appear as large as 13 arcminutes across and as bright as the full moon. Heaphance has 23 dwarf moons, many of which are bright enough to be faintly seen as distant as the orbit of Xua.

Due to its large size and brightness, Heaphance is one of the most distinct planets of the Panthian system, and is sometimes poetically referred to as Pantheus' Third Sun. Heaphance was the first planet found and cataloged by Sylvester Arsiza, and one of his briefest researched.

Oaven

Torrid clouds sweep across Oaven's water vapor atmosphere.

The second planet from Cthnos, Oaven (/oʊeɪvɪn/, oh-AY-vin) is a torrid A-class Venus analogue almost two times the mass of Earth, and is by far the hottest Panthian planet. Oaven has a diameter of around 1.1 Earths, and is composed of a substantial mantle around an iron core. The conditions on the planet are incredibly hostile, as its with surface conditions generally exceeding 2000 °F. The surface of Oaven is mostly dark igneous rock, and is scarred by the planet's active geology. Oaven's many volcanoes contribute to its runaway greenhouse atmosphere of water vapor and carbon dioxide, which weighs on the planet with a crushing 373 atm. From space, Oaven appears bright, tan in color and is covered in cream colored clouds of carbon dioxide. Oaven has no moons, but both Heaphance and Geltrest can be seen large in the sky from the planet's orbit.

Oaven's hot, super-Venusian conditions have led to its reputation as a "hell planet" and a place of pain and banishment. Various missing person cases in the area have been attributed to tourist ships crashing into the planet and disintegrating in its stratosphere, though only one such incident has been officially confirmed.

Geltrest

Massive storms rage among the cloud bands of Geltrest.

The third planet from Cthnos, Geltrest (/ɡɛltrɛst/, ghelt-trest) is a warm J-class planet of twelve Jupiter masses. Geltrest is primarily composed of hydrogen, water vapor and helium, with a small core of silicate and iron. Geltrest is the fourth largest (1.1x the diamter of Jupiter) but second most massive Cthnoite gas giant. It has the fastest rotation of any Panthian planet, with a day length of 7 hours and 27 minutes. The planet's appearance is defined by bands of brown and orange gas, which are generated by the planet's internal heat left over from accretion. Geltrest is notable as its axial tilt is 64° off the Cthnoite ecliptic, which causes the planet's gas bands to appear diagonal and exposes its polar vortexes to observation from other bodies in the plane. Gelrest has one large moon, Sauri, as well as a system of 49 small irregular moons, many of which orbit retrograde. Gelrest is large and close enough to appear as a disk around the orbits of Oaven and Xua. Given the planet's axial tilt, its lunar system is also visible as a strenuous cloud of stellar brightness bodies orbiting the planet, distinctly vertically.

Geltrest is frequently cited as a Jupiter analogue, given its similarly colored bands and storm comparable to the Great Red Spot As the most massive inner Cthnoite planet, minor bodies which orbit inward of the orbit of Mauru are referred to as "Gelrester bodies." Geltrest's immense gravity is likely responsible for pulling Xua inward and stunting its growth, as gravitational perturbations would've prevented Xua from absorbing additional planetessimals.

Sauri

Sauri's bright white sand dunes contrast with the planet's dark mare regions.

Sauri (/saʊriː/, SOWR-ee) is the third moon of Geltrest, and the only rounded moon of the Geltrester system. Sauri is a warm, D-class, tidally locked desert moon of .06 Earth masses. Sauri has a diameter of .4 Earths, comparable to Mercury, and is composed of a silicate mantle around an metallic core. The moon has a thin, brown atmosphere of sulfur dioxide with trace amounts of octane and chlorine, thought to have emerged through volcanic outgassing. The surface of Sauri is split between igneous mares and rocky features on its nearside and the vast Eddenter Desert on its far side, where temperatures can rise as high as 175°F. Some volcanoes dot the Saurian surface, and then presence of canyons may indicate that the moon had liquid surface water in the distant past. Sauri's orbit on the Geltrester plane makes it a particularly easy observation for telescopes, as even minimal magnification can resolve the body distinctly from Geltrest.

Sauri, as an incredibly hot desert world with a poisonous and thin atmosphere, is neither inhabited nor a coveted tourist destination. Strictly in-spaceship tours are offered through the planet's north pole auroras, where visitors can observe the massive form of Geltrest looming above the twilight.

Xua

Xua's exotic atmosphere gives the planet its distinct color scheme.

The fourth planet from Cthnos, Xua (/zuːʌ/, zoo-UH) is a temperate D-class planet of .2 Earth masses. Xua has a diameter of .59 Earths, comparable to Mars, and is composed of a silicate mantle around a metallic core. Xua is the second smallest and least massive Panthain planets, after Liana. The planet has a substantial atmosphere of .8 atm, composed of nitrogen, sulphur dioxide, carbon dioxide, hydrogen sulphide and trace amounts of acetylene, ethane and carbon monoxide. The prominence of nitrogen and sulfur dioxide in its atmosphere give the planet its distinct teal appearance. The surface of Xua is a global desert with an average temperature of 104°F, made of sedimentary rock and sand dunes. The surface of the planet is covered in many canyons, indicating it likely used to have a water cycle. Xua was named for for the X shaped Xumite crater on the planet's surface.