Big Comet
HD209458b.jpg
(star's supposed to be white… it's the best I could find on short notice)

Description

Also known as Coma, or BC. This world, despite it's harsh environment and closeness to it's star, is the most heavily inhabited solid world in the Sirius Star System with over 200 million inhabitants. It's name is derived from the massive tail of water vapor which results from the solar wind blasting away it's atmosphere when the planet makes a close approach in it's eccentric orbit.

The eccentricity of the orbit is thought to be caused by the frequent close approaches of the Pup, Sirius's smaller stellar companion who's orbit shifts between 20 and 10 AUs every 50 years or so. It is thought that Coma originally formed much further away from Sirius, as evidence from it's high concentrations of water, and was flung into it's current semi-stable orbit some 10 million years ago. This is a relatively short time, on cosmological scales, which explain why not all of the water has been blown away. Simulations suggest that in “only” a few more millions of years, the planet will become quite dry.

Though this timescale is ludicrously long for human refference, this countdown has sparked a healthy competition among water hunters, with the frequent joke that they had better mine the water “before it's all gone”.

Planetary characteristics

Orbital Position: 2
Distance from primary: 3.2 AU
Orbital Period: 1648 days (~4.5 T-years)
Rotation Period: 25.5 hours
Sattelites: 3 naturals, 4 diverted asteroids
Population: 204 million
Major Exports: Water