Cyran is a Super-Jool gas giant added in the Kopernicus pack Planet Cyran. It is a hot, orange planet
generating its own heat and has a fiery ring system. Cyran orbits between Duna and Jool, and has 6 moons. One of these moons is a relocated and re-textured Dres. Two of Cyran's moons have oceans, while one is potentially habitable.
"A huge and somewhat angry looking gas giant, Cyran is as much loved as it is feared. The decay of radioactive elements in the planet's core have heated up the planet, and thus it seems to glow. It is also quite warm close to this planet due to the heat generated by the radioactive decay, so be careful with aerobraking, you might just melt from the sheer temperature of the atmosphere."
Cyran is a "Super-Jool". These are large gas giants with a greater radius and mass than Jool in the stock KSP system. It has a radius of 8,000 kilometers, or 1.3 Jool Radii. Cyran also has more than twice the gravity of Jool and 2-4 times its mass. This results in the planet having a radioactive core and huge amounts of released heat, getting it close to the level of a Y-Class Brown Dwarf.
Cyran's atmosphere starts at 500 kilometers, with 20 times the pressure of Kerbin's atmosphere. The radioactive decay of the planet's large core heats the atmosphere to about 700 Kelvin. This is equivalent to 800.33 Fahrenheit, or 426.85 Celcius. While nearly twice the temperature of Eve, Cyran's atmosphere is still slightly cooler than that of real-life Venus.
The atmosphere of Cyran has several distinct cloud features. It has a few prominent jet streams running alongside glowing cloud belts that contain air from near the planet's core. There is one huge superstorm in Cyran's atmosphere, along with multiple smaller ones. There are an equal concentration of these mini-storms in both the Northern and Southern hemispheres of Cyran.
Cyran is unique for being one of the very few gas giants in a Kopernicus planet pack to have biomes. There are 5 in total and mark prominent features in Cyran's turbulent atmosphere.
- Lower Storms (Black)
- Upper Storms (Blue)
- Jet Streams (Green)
- Glowing Bands (Red)
- Superstorm (White)
Cyran has a narrow band of brightly glowing rings. These are made from material shred off from the half-molten moon Infernas. The rings of Cyran are heated to well over 800 Kelvin.
Cyran has 6 moons.
- Zerto: A small purple and grey planetoid captured in a retrograde orbit around Cyran.
- Sennim: A blue-green moon similar to Titan with a thick atmosphere and lakes of liquid Mercury.
- Infernas: A rocky moon with a decaying orbit that is being torn apart by Cyran. One side is pure lava, while the other is mostly made of basalt.
- Kivlan: A beautiful cyan ice moon with a decently thick atmosphere and vast mountain ranges.
- Iltan: A Kerbin-like moon with golden land masses, a breathable atmosphere, and oceans of water.
- Dres: This is a remade version of Dres. It is a crimson-grey moon with steep ridges and lots of craters.
- Despite not being based off of any known exoplanet, Cyran bears similarities to the planet J1407b.
- Cyran is the only gas giant, besides Jool from Jool Biomes, to have multiple biomes.
- Planet Cyran is the only planet pack that moves and remakes Dres while keeping the rest of the Kerbol system the way it normally is.
- Planet Cyran is one of the few planet packs to feature a gas giant with a custom normal map.