Calida, Latin for warmth, is an exoplanet orbiting the star Solis, a G7 main sequence. At an average distance of about 200 million kilometers, it would seem too cold for life to form in liquid water. But due to a fortunately high amount of heavy metals, lanthanides, and actinides that helped form it, it has a core bursting with magnetic and thermal energy, raising its temperature.
When Calida was first discovered, it's variety of life astounded scientists and society alike. But no one was prepared for the nightmares Calidean cladistics had to offer. Animal-like organisms evolved at least 3 seperate times, if not more.
Density: 6.23 g/cm^3
Radius: 5797 km
Aphelion: 141 935 741.578 km
Perihelion: 148 195 258.372 km
Orbital Period: 595.06 days
Rotational Period: 30.1 hours
Precession cycle: 20,500 years
Surface pressure: 28.934 psi(sea level)
Minimum temperature: -106 C°
Median temperature: 11 C°
Maximum temperature: 39 C°
Calida is the third planet from its sun, with Calx, Millus, and Gahenna as you move in. Gahenna's best description is to combine Mercury with Mars and crank up the heat beyond Venus. Tidally locked to Solis in an orbit 11 days long, it's not surprising to find out that Gahenna's thin band of twilight is hot enough to melt lead and lithium. A sea of magma has even formed on the extreme sun side and is meta-stable. Millus orbits every 103 days with the fastest rotation of any planet known at 49 minutes. Other than its rotation, Millus is the most boring planet in the system; it's essentially a ball of metal with lots of rock impurities and an atmosphere thinner than Mercury's. Calx only orbits a few days faster than Earth, but is rather eccentric, the differences between its aphelion and perihelion about 30 million km. It might have been a habitable planet had it not gotten knocked close enough to the sun to boil water during its orbital summer. Not exactly friendly to organisms made of water.
Beyond Calida is Aiolos, jovians Nubes, Geminus, Chronis, and plutoid Khione, with 6 more yet-unamed planets moving far into the Oort cloud. Aiolos marks the boundary between terran and jovian with a mass of 15 earths and an atmosphere worth half an earth. Nubes is a typical jupiter, but more massive with a larger volume and greater density from its cold orbit. Khoine is an ice planet made almost entirely out of water, methane, and CO2 ices with some other hyper-chilled aqueous solutions. At first glance it just looks like the biggest ice cube ever, but it's massive enough to pull itself into a spheroid and clear its orbit, so it's a planet. Pluto has been avenged! As for Geminus, it is quite... let's just say-special.
Geminus was once two planets, named Gemina and Gemino. Gemina orginally formed at about 1 Jupiter mass, while Gemino was closer to that of Saturn. Each formed in their own seperate orbits about 20 million km apart with Gemino further out. Just barely stable enough to maintain their orbits, but The Great Disturbance simultaneously sent a flurry of asteroids into the system and messed with the inside of the system itself, effectively altering their orbits until they overlapped-twice. No amount of resonance could stop the inevitable after that. Gas and dust flew everywhere when the two planets connected. It might have been the end of Gemino, but gravity and inertia had other plans. Gemino's core got caught in Gemina's gravitational pull, but was moving with enough inertia to just simply swing back around and repeat. The two cores began orbiting each other like binary planets, their conflicting magnetic fields creating a near-void of ionized plasma within the planet. The gas swelled around the gap to form a semi-lobed sphere. With two cores orbiting each other every 9.6 hours, possibly the strangest planet in the galaxy was born.
Chronis is a large, light-green gas giant, so named for its peculiar rotation, revolution, and satellites. It rotates every 10 hours, its year is 100 earth years, and it's 3 moons orbit in a 1:2:4 resonance. Even its orbit is almost a perfect circle. How Chronis got this way lies in the many factors created by The Great Disturbance.
But enough about Calida's neighbors. Let's focus in on Calida itself.
Calida consists of a much more even blend of elements than Earth. It's estimated that Calida is as much as 27% lanthanides and actinides. Noble gases make up a whopping 16% percent of it's atmosphere, which is strange, especially for such a small planet. It has probably kept it's atmosphere less because of gravity and more because of it's magnetosphere, massive compared to Earth. Many explanations have been cooked up as to why the planet has such a strong magnetic field, the best being that the extra density of high amounts of heavy metals compress the planet enough to produce a small inner core, no more than 670 kilometers in diameter. The lanthanides present in this inner core form a matrix with the magnetic elements present, producing a much stronger magnetic field.
Calida first formed 5.6 Gya like nearly any rocky body, but with some interesting materials. The system itself formed from a cloud of more evenly dispersed elements with a larger amount of heavy metals. These elements were just barely spaced out enough to prevent condensing, but then a nearby star just had to blow up and condense it with a supernova and add to its heavy metal count. When fusion started and Solis was born, a large amount of proto-planets had already formed due to the high density in the gas disk. Solis feasted on the dust cloud and grew, spinning faster and faster. The heaviest elements gathered at its equator and were ejected, encouraging planetary formation even further. The planets were mostly established only a few million years later. Calida was smaller, only 80% its current size. But that was soon to be remedied.
The Great Disturbance-5.49 Gya to 5.46 Gya Edit
The Great Disturbance occured when a hyperbole star passed by the system. It caused a great deal of havoc on the young Solis System. A F0 star, it was so big and close it looked like a moon from Calida. It pulled on the entire system in passing and changed the fate of every planet in doing so. It altered the orbits of every planet directly and/or indirectly and flung in bodies from the edges of Solis' reach. Millus was hit and its rotation sped up to its current state, Calx was pushed and pulled into a weird orbit, Geminus was born-I could go on. But perhaps the most affected out of all of them was Calida.
The Morris and Circum Collisions-5.47 Gya to 5.46 Gya Edit
A small planetesimal almost the size of the moon struck a glancing blow at Calida, completely destroyed in the process. The ejecta collected into a moon, Morris, about 13,000 km away from Calida. Morris would later be responsible for most of Calida's tides so life was encouraged to go on land, but there was a more pressing problem on hand. The collision caused the planet's rotation to come to almost a complete standstill, like Venus in our solar system. Calida would have been stuck tidally locked to Morris had it not been hit again-this time by a body the size of Ceres. It picked up rotational speed from this impact, giving it a 29 hour long day-something photosynthetic life could handle easily. Since then, the day has lengthened to 30.1 hours long. And what became of this small body? Half of it was ground into Calida, while the other half spun wildly away into an orbit about 50,000 km away. I quite literally mean spun away-this thing was rotating every hour or so on an axis less stable than Nix's. Nearly liquefied, the denser portions of it gathered on the Calida side, but don't think it's about to tidally lock in the conventional way. Like I said, this thing was a bucking bronco! So what was the path of least resistance? Make the axis align with the denser parts and Calida's center-which is exactly what happened. With one side facing its planet at all times and still rotating every 20.4 hours, Circum became the oddest moon on record.
The Calming-5.45 Gya to 4.45 GyaEdit
The hyperbole star passed and let loose its grip on the system, letting things settle. Chronis established its odd behaviors and Khione was born. Everything settled into a stable condition. On Calida, the oceans and atmosphere were forming, establishing some currents. Volcanic islands popped up everywhere. Soon, the first lifeforms would be born.
Pre-Kimibrian-4.45 Gya to 2.8 GyaEdit
This is the period from where life evolves to the point where Calidean life as we know it starts to branch off into the major clades.
Primitrius-4.45 Gya to 3.3 GyaEdit
This period defines the span of time from the birth of the world ocean, across several lucky or unlucky replicating molecules, to the birth of the first Celi.
The Preceli are the first domain of life to appear on Calida. They bear a strong resemblance to bacteria on Earth, but have large para-ribosomes called formosomes and a nucleus similar to a virus packet. Flagellum are also different, resembling cylinders with fibers through the sides. These 'flagellum' are called "Fistulam", Latin for pipe. Fistulam differ from flagellum in the fact that they suck in and squeeze out to provide propulsion instead of whipping. The Preceli have started out as lithotrophs, anaerobic microbes, organotrophs, and even magnetotrophs, but will soon diversify into all life on Calida.
Viridium-3.3 Gya to 3.1 Gya Edit
The Viridium is the beginning of photosynthesis on Calida. However, this has a twist from normal earth life. The photosynthesizers don't get transferred to a more advanced cell like it probably happened with cyanobacteria and plants here on Earth. These Preceli become more advanced celi, called Semiceli. The Semiceli differ from the Preceli in that they have thylakoidions, which almost no Preceli have, they have a greater and lesser formosine, which are essentially formosomes fused together to make a larger container holding amino acids or fatty acids, and in later forms, they have a Creovesiculam, similar to eukaryotes' "Golgi apparatus". They were also capable of forming structured colonies similar to slime molds, but more concentrated. They're also described as microbial mats with proto-legs similar to fistulam. The first multi-celi were born out of these congregations. These slime mold forms are categorized in the phylum Kalaikii, after greek for 'mat'.
As the Semiceli spread, a new clade of the Preceli evolved. They resemble mitochondria before the convergence with eukaryotes. In a way, that's what they are. But they have a fate larger than becoming cellular powerhouses.
Eolian-3.1 Gya to 3.0 Gya Edit
The Eoceli were the second multi-celi to come around. These evolved from the Preceli, not the Semiceli. Resembling a cross between a eukaryote and a mitochondrion at the cellular level, they diversified into a race of active creatures. All mostly cylindrical in shape, the Eoceli have a mix of bilateral and radial symmetry in their anatomy. Their front bears four to seven holes, three to six in a circle around the center and one centered split hole for inhalation. Exhalation is accomplished through a hole on the dorsal side of their bodies. Their bodies can have anywhere from two to sixteen limbs, ending with a tapering tail.
All heterotrophs, they range from filter-feeders to apex predators. The largest of them could grow up to 20 meters in length and 2 meters wide. Their skeletons were most likely made of a specialized collagen that was mineralized to provide support. However, fossil evidence indicates that the Eoceli had very strange muscular systems due to the strange shapes the skeleton went under in order to get best mechanical advantage. The best science can come up with at the moment is that the Eoceli are the first domain to exhibit 'twisting' muscles instead of tensile or compressive muscles. The best analogy available is the wringing of a towel.
Near the end of this period, Kalaikii had begun making marshes and swamps on land filled with pads of moss-like foliage. These forms had evolved a completely sessile life stage, using their proto-legs as roots. Because of their limited morphology, however, the transition onto land stunted their evolutionary growth and kept them from becoming more than far reaching pads of moss before other Semiceli gained dominance.
The Eoceli had a wonderful part on the stage of evolution. Species showed a wide range of characteristics, from whale-sized filter-feeders and predators to signs of high intelligence, from ramming behavior to spear-like projectiles. In their prime, they began plans to colonize the land with muscular limbs and the beginnings of toes and fingers. But their dominance could not last forever.
Silicaceous-3.0 Gya to 2.8 GyaEdit
The way life evolved on Calida meant that silicon and silicates are poisonous to Calida's lifeforms in a powdered form. Fortunately, such compounds are acutally rare in Calida's region of space. At least, they were before an asteroid high in silicates coming from the outer regions of the Solis system rammed into the surface, littering the oceans with deadly substrate. The Eoceli barely stood a chance and nearly died out. Except as vesichondrion organelles in the Semiceli, only one or two species survived: a complete domain virtually extinct. The Preceli evolved too quickly to be completely exterminated. That leaves the Semiceli.
The Semiceli's creovesiculam saved them by creating a vesicle designed to absorb the silicon as it entered the cells. Later on, this gives the Semiceli another surprisingly useful advantage, but for that moment, the Semiceli were the dominant multiceli on the planet. They quickly radiated into many new forms, some evolving to become more animal-like, and some evoving to become more plant-like. Eventually, there were four main clades: the Kalaikii, the Polyboli, the Diakladosii, and the Anacatemae. The Polyboli superficially resemble pagodas. The Diakladosii resemble soft corals and kelp. The Anacatemae somewhat resemble nudibranchs, annelids, and lobopodians, with their biggest differences being silicon eye lenses. All are descended directly from the Kalaikii.
Beyond this point cladistics are still being determined. Between poor fossilization of most Calideans, high levels of specialization early on, and numerous examples of convergent evolution, not even combined efforts of morphogenetic and molecular studies reveal much about their evolutionary history.
Primozoic-2.8 Gya to 2.14 Gya Edit
Kimibrian-2.8 Gya to 2.72 Gya Edit
Life began to really explode and diversify: Calida's Cambrian. The biggest difference is that there was life on land, a simple ecosystem, in fact. Here resided remnants of the Eolian: sheets of kalak moss and clumps of land sponges hug the rivers, while further in where rock and wasteland resides are microbial mats and sheets of magnet fungi with derived thylakoidions and magnetoplasts are scraped up by the few surviving Eoceli. They have managed to keep this niche of feeding on magnet fungi up to the present day.