Fhrisso

Overview
Fhrisso, or CelWP T31, is a relatively small post-Asymptotic Giant Branch star. It is home to 3 planets, and through mass loss has generated the Infinity Nebula. Fhrisso is also a W Virginis cepheid and an RV Tauri variable (RVb), variating by around 1.8568 magnitudes over ~27.3 days. It was added in Release 9.

Properties
Fhrisso is quite small for a post-AGB star, being at just around 30 solar radii, and quickly decreasing in size. It is relatively heavy for one as well, being about 0.782 solar masses. It evolved from an A type star, and is around 1.3 billion years old, but incredibly close to dying, having just around 1,700 years left of its life, comparable to some of the hottest WOs like Gisugda, in GASCA. Fhrisso is slightly oblate, mostly because of the relatively quick rotation for a star expelling so much mass at once. In fact, Fhrisso is losing mass so quickly it's lost 0.05 solar masses in the last 300 years, making the protoplanetary nebula which surrounds it. There is very little carbon in Fhrisso's atmosphere, for unknown reasons.

Around 800 years ago, Fhrisso crossed the AGB stage, quickly losing mass and shrinking and becoming hotter and hotter. At this time though, the protoplanetary nebula which surrounds Fhrisso should not be ionised, yet it is. Fhrisso will quickly start brightening to the point where it may just entirely evaporate the nebula soon.

Planetary system
Fhrisso has 3 planets.


 * Arrenave, a charred, small rocky planet with oceans of lava and strange patches of dark red stuff across the surface.
 * Scilstria, a ringed icy planet with lakes of water. Its atmosphere is being blown away by Fhrisso's ejected matter. Scilstria has 3 captured asteroid moons.
 * Vigaret, a bluish ice giant, not very noteworthy. Vigaret has one major moon, Korener, which has strange unexplained patches of different colours.

WIP