TFX
Introduction
TFX is a large, Population I star in a distant galaxy, home to a planetary system, the TFX System. The star emits most of its energy in the form of infrared and visible light, with a peak at 440nm, and with approximately 16% in the ultraviolet; its luminosity places it into the F6V spectral class. It is the most important source of heat and light for Vosanus and its inhabitants and ecosystems. TFX produces a magnetic field via convection in its interior. The star and its system formed approximately 5.01Ga ago, wherein they underwent the proccess of proto-system formation and accretion due to gravitational collapse. The star has an approximate maximum lifetime of 5.8-5.9Ga. TFX is of importance to many cultures and religions living on Vosanus, and is integrated into most calendars for the purposes of tracking seasonal changes.
TFX is composed of mainly hydrogen and helium - its metallicity is 0.0124, and so it is composed of approximately 1.24% oxygen, carbon and iron. The remaining 98.76% is hydrogen and helium. The star undergoes nuclear fusion in its core in order to prooduce heat and light. Through this proccess, TFX fuses 5-6 billion kilograms of matter every second, which also results in the creation of intense streams of charged particles called stellar winds.
In approximately 600 million years, the hydrogen fusion within the core of TFX will cease to keep the star in hydrostatic equilibrium, and it will begin to increase in temperature and density. This begins the process of stellar death, wherein the stars spectral class will change into that of a supergiant, as its outer layers begin to expand due to increased outward pressure. This will result in the definite extinction of all life on Vosanus, and will also destabalise the TFX System. The outer layers of the star will then shed, in a supernova event, and the remaining mass will become either a white dwarf or a black hole, as the denser material collapses in on itself.
Formation
TFX formed approximately 5 billion years before the present day, due to the collapse of a molecular cloud of hydrogen and helium gas under gravitational attraction. The star's rotation was started in this early period due to the conservation of angular momentum within the cloud. Gas and dust on the exterior of the newly formed star with sufficient momentum to escape collapse instead began to orbit and flatten out around the star and eventually became a protoplanetary disk, which would result in the formation of planets and objects around TFX, including Vosanus itself.
After leaving the early stages of star formation, TFX would enter the main sequence of the HR model of stellar evolution. It is an F type main sequence star and is about 80% of the way through its main sequence evolution. Currently, TFX is getting hotter, brighter and larger in radius over time; it increases in brightness by approximately 1% every 90-100 million years, and has increased from its previous zero-age brightness by 60% - from a previous brightness of 1.2 solar luminosities to the current brightness of 2.07 solar luminosities (approximately 8x1026 Watts). Within the core of TFX, on average, around 6 billion kilograms of matter are converted into energy every second. This produces solar radiation and sustains hydrostatic equillibirum within TFX, preventing it from collapsing inwards.
After its main sequence lifetime, TFX will leave the main sequence and undergo a new phase of stellar evolution. As it only has a mass of 1.2 solar masses, it is insufficiently large to undergo a Type II supernova event when - instead, in approximately 1-1.5 billion years, it will lose the ability to fuse hydrogen and it will gradually increase in luminosity and size by almost 1000 times its current brightness, becoming a red giant star. After this, in approximately and the outer layers will gradually shed