KOTALI'ZAPA (Great Wall Star)
In hoku astronomy, Kotali'zapa is the brightest system in the Great Wall constellation, during the autumn in the northern hemisphere this constelation stands above the horizon in a line with five other distant bright stars, Kotali'zapa being the brightest and closest of them. In Sidessian, the common spoken language of the system, the star has the name of Volkali, which means Belt Buckle in sidessian, as the peoples of the region saw the line of stars as belt constellation.
Kotali'zapa is a young triple-star system, and with its brightest component receiving the same name. The other two companions are a orange and red dwarfs in a binary configuration. This system configuration isn't particularly uncommon, though, the friendliest of worlds here is considered quite a spectacle to behold.
STARS
spectral type ID'd through temperature, luminosity might differ from real world stars with same type
KOTALI'ZAPA / VOLKALI, Alpha of the Great Wall / The Buckle
F5V yellow-white star
Temperature 6540 K
(in solar units)
Mass 1.27
Luminosity 2.40
Radius 1.21
Metallicity Z* ~0.789 [Fe/H]
Abs. Magnitude +3.87
Rotational period 13 days
KOTALIMOKU, the Wall's Capitain
K8V orange dwarf star
Temperature 4010 K
(in solar units)
Mass 0.39
Luminosity 0.052 ± 0.004 (x-ray variable) (64% visual luminosity of the Sun)
Radius 0.47
Metallicity Z* ~ 0.662 [Fe/H]
Abs. Magnitude +8.05.
Flaring BY Draconis variable star, emitting x-rays bursts every 36 hours.
Orbital separation from parent star 2.5 AU or 375 million km on average.
Orbital eccentricity 0.125
Orbital period ~ 3.0 Earth-years
NIGUTAL'ZA, the Wall's Spotter
M1V red dwarf star
Temperature 3655 K
(in solar units)
Mass 0.29
Luminosity 0.0025 ± 0.01 (x-ray variable)
Radius 0.35
Metallicity Z* ~1.35 [Fe/H]
Abs. Magnitude +9.07
Flaring BY Draconis variable star, emitting x-rays bursts every 40 hours.
Orbital separation 0.32 AU or 48 million km on average.
Orbital eccentricity 0.112
Orbital period ~ 80 Earth-days
PLANETARY SYSTEM
Kotali'zapa systems posess five planets, four of which are located around the binary dwarfs.
b) KOGEZA, the Giant
A pale blue hot-jupiter around of Kotali'zapa at 0.67 AU, 1.74 Jupiter-masses and 11.8 Earth-radii, its upper atmosphere is full of sulfides and chlorides at 140°C.
c) VOLILOSHOKU, the Fixed-Shadows World
A superterran with a shallow global ocean, in which native harmless microbes thrive, the world was once home to chelok and hoku settlers long before the Fall of Hokushoku. For being locked in the L4 lagrange point of the star Nigutal'za, the two dwarfs are set fixed in the sky from the planet's perspective, hence, it was aptly named Locked- (vo) -sunbean- (lilo) -world (shoku). Though, this planet along with its star take about 80 days to orbit their parent star Kotalimoku, so the whole system slowly turns along its orbit, pointing the planet towards and then away from the brighter star at the center of the system, giving it seasons in cycles of 80 days.
It gets 0.75x solar constants (and 0.5x luminosities) from its two parent dwarfs, plus 0.38x solar constants (and 0.4x luminosities) from the brighter star, on average. This makes the planet's temperature stay around 4°C, but over the course of those 80 days the temperature fluctuates 26 K above and below that average, and over the course of 3 years it ocillates more 22 K above and below whatever the current average is because of its eccentricity around the brighter star. For an observer in the tropics, the water would at times simmer at 60°C during the hottest summer, or freeze at -34°C in the coldest winter, getting even colder towards the poles of the planet, and at night, where it has reached historical lows of -150°C.
Those extreme and fast temperature variations create all sorts of climate intempers, rainstorms, hailstorms, and hurricanes are the default weather here, while seeing a beam of sunlight through the clouds in a day without wind is considered a gift from the gods.
However, despite the attractiveness of setting up a settlement in the equator, the x-ray bursts of the two parent stars would make maintaning a health standard, as well as exploring the surface, quite problematic - so both ancient chelok, and hoku settlers arrived to the conclusion that one has to inhabit the chilling poles of the planet to live on the surface, or build underground facilities in the twilight zone. The largest hoku settlement was the capital Kipishahit (Turning-Table, I suppose this has something to do with the clay-rich soils), though various smaller settlements existed throughout the planet, and the only reliable mode of transport over long distances is to fly, or wait until nightfall to run trucks over the ices.
d) NIGUTALINE
A rocky terran around Nigutal'za, its temperature varies between 140°C day side to -140°C on the nightside. Its barren surface is peppered by craters, while sporting solified lava flows, the geologic record tells that this was once a wet venusian kind of world, having its atmosphere blown away to a thin ghostly veil, its polar ices form gigantic pillars and glaciers. The ices were once mined here and taken to space habitats around the binary.
e and f) Unnamed Waterworlds
Planet e and planet f are two massive seasonal waterworlds, they get little light from their parent dwarf stars, instead, their main light source being the bright star. The thick atmospheres are able to hold onto decent heat and water in the surface, which freeze at -60°C during winter, and melt at 20°C during summer over the course of 3 and a half years. The atmospheres of these worlds however are made predominantly of nitrogen, oxygen, and ammonia, in proportions not suitable for life, the ammonia clouds and vapors are not enough to deter the harmful sun's rays, so they were not chosen by the colonists upon arrival back in 1150 SE.
TRIVIA & LOCATIONS
The extreme X and UV rays Voliloshoku gets every few days are the primary source of oxygen in the atmosphere, at it breaks down water and carbon dioxide into oxygen, sooth, and organics in the upper atmosphere, which rains down to the surface. The bacteria in liquid water metabolizes whatever it can while it is warm, leading to huge blooms which last a few weeks, producing a foam and a thick sirupy substrate or slime made of sugars, mucins, proteins and vitamins which they do not need during the day, starting to feed upon it as the temperatures drop and night comes. The substrate forms a hard leathery cover when exposed to the cold which insulates ponds from x-rays and the freezing temperatures outside, with some strains of bacteria here being commonly farmed for food by colonists.
A historical population of 1.2 billion colonists once inhabited the planet, making up for 4% of the Expanse's native population, being the 4th most populated outworld.
Theories suggest that Voliloshoku had a much thinner atmosphere in the past, but due to volcanism and intense photolysis of its water, it has been thickenning by a measurable amount every millenia. This would explain why, despite the current inhospitable conditions, this planet has this kind of primitive life, however doomed to extinction in a future Wet Venusian.
MORE COMING SOMEDAY!
- M. O. Valent, 08/02/2023
- M. O. Valent, last updated 15/02/2023
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