Persephone

Discovered in 2037, Persephone is the 9th planet of our Solar System, orbiting just beyond the Kuiper Belt within the darker reaches.

Physical Characteristics

Much like Uranus and Neptune, Persephone is an ice giant, only being slightly smaller than Neptune. It is however, more denser than Neptune, and thus marginally more saturated in appearance. As with most ice giants it is composed mainly of Hydrogen and Helium, along with trace amounts of Methane and other gases.

Climate

Persephone's weather can be characterised by high speed winds and storm systems. Although not as fast as Neptune's, the winds on Persephone race around the planet at immsense speeds up to 900-970mph. Temperatures drop down to around -244 °C.

Immense lightning storms have also been observed, which briefly light up small areas of the planet, some large enough to be seen from its moons. Cyclonic storms also form here, although not as great as Neptune's dark spot, with the largest of them being just larger than Luna.

Orbit and rotation

Persephone takes approximately 1,797 years complete its journey around the Sun, and has an elongated, oval-shaped orbit. A solar day lasts roughly 11 hours, making it have the third shortest day in the Solar System.

Due to the tremendous distance, the Sun only appears as a very bright star from Persephone.

Formation and history

Persephone is believed to have formed much closer to the Sun in its prehistory until a close encounter with Jupiter sent it flying towards the outer edge of the system. It is speculated that its moons may have been Kuipter Belt Objects that were captured by Persephone during its journey to the outer reaches.

Others even speculate that Persephone may not have orginated in the Solar System, and was instead a rogue planet captured by Sol's gravity at an unknown point in the past. Though a popular hypothesis, evidence and research suggests that Persephone is indeed, solarian in origin.

Moons

Persephone is orbited by 13 moons, with 3, Melinoe, Zagreus and Dionysus, having achieved hydrostaticequilibrium. The rest are merely captured asteroids.

Moon Table
Image	Name	Description	Size	Orbital period
	Arachne
	Melinoe	The closest major moon to Persephone and the second largest of the three. It is an airless world, very similar to Mercury or Luna, being slightly smaller than Jupiter's moon, Callisto. It takes around 20 hours to orbit Persephone and like most moons, is tidally locked to its parent, meaning days last the same length as the orbit. Melinoe's surface is surprisingly smooth for a world of its type, with craters being infrequent. Because of this, it was the first Persephonian moon to be landed on and research sites have been built around it. The temperature remains at a frigid -247°C. Research suggests that Melinoe formed more further out into the Sol System, in a more calmer region where it wasn't impacted as much prior to capture.
	Zagreus	The second major moon, a heavily cratered world, contrary to its sister, Melinoe. Zagreus takes 36 hours to orbit the planet, with a surface day lasting the same. It is between the sizes of Melinoe and Jupiter's moon, Io Surface features The surface of Zagreus is very rough, with craters taking up most of the landscape, creating extreme cliffs and jagged mountains. Outside of an unmanned lander, there have been no attempts to land on Zagreus for this very reason. Its theorised that Zagreus formed in a very packed region of the early Solar system, where it was subject to constant bombardment and collisions thanks to the complete lack of an atmosphere. Temperature is around -248 °C.
	Dionysus	The third major moon of Persephone and arguably the most interesting, with its seemingly active core and thin atmosphere, bearing a slight resemblance to Saturn's moon, Iapetus. Active geysers, akin to those on Triton, have been observed on the surface, reaching nearly 1km in the air.
	Gorgo
	Cyane	Named after a water nymph who Persephone befriended in Greek mythology. Cyane is an interesting moon, partly due its icy cover, despite being an asferoid. It is around 220km wide, making it the fourth largest moon of the planet.
	Iacchus
	Minthe	The furthest and the smallest moon of Persephone, only being 20km wide, having an unusual elongated shape.

Discovery and Exploration

The existence of a ninth planet had long been speculated by astronomers, due to gravitational disturbances within the Kuiper Belt. It wasn't until 2037 when this far off world was finally confirmed to exist.

The unmanned Trailblazer Probe was sent to this far-flung world 2070s, and sent back images, detailing the ominous, dark blue sphere that had lurking at the Solar System's edge for so very long.

As of today there are some research stations scattered around Melinoe, as its close orbit to the planet make research there easier. There are no major colonies or permanent residences here though, as its isolated location and low-light make it unsuitable for such a thing.