I've been taking an astronomy class recently (just 101, pretty basic stuff) and we're learning about stars currently. I was wondering how did your creators classify stars and the stages of their life, and what kind of star does your planet orbit (I'd assume a yellow star but I wouldn't be surprised if it was another type of low-mass star).
TSAC: Stellar classification has followed many different definitions since antiquity, however the most contemporary definition follows a lettered system based on a star’s spectra. This can be simplified to describing them based on their “color”, which also corresponds to their temperature, due to their nature as blackbodies.
Stars can also be classified by their luminosity, or brightness. By plotting stars on a graph based on their brightness versus their temperature, a fascinating structure emerges: Most stars can be found in the middle of the graph, on a rough line known as the Main Sequence. Stars spend the majority of their lives on the Main Sequence, but begin to diverge as they reach the end of their fuel supplies.
Older stars which have exhausted their main hydrogen reserves will expand, increasing their brightness, but also lower in temperature, becoming cooler, more luminous stars known as Red Giants, found in the upper right of the diagram. After exhausting their secondary helium and oxygen reserves as fuel sources, lower mass stars will eject their outer layers and leave behind a stellar remnant known as a white dwarf, which can be found clustered in the lower left of the diagram.
Higher mass stars are able to synthesize higher and higher mass atoms into fuel until they start fusing elements into iron. Fusion of iron is an endothermic reaction rather than exothermic, meaning that it takes more energy than it releases. Thus, when a star begins to create iron in its core, its outward pressure can no longer hold up under its intense gravity, and it begins to collapse.
The collapsing of a star is one of the most violent processes in the cosmos, and it can compress the remaining core of the star into a mass of degenerate matter known as a neutron star. In some cases, however, the star is massive enough that even the core cannot hold up under the star’s gravity, and the star collapses into a singularity, a black hole.
Our own star is a K-class dwarf, located firmly on the main sequence. Though its light appears white, K-class stars are often colloquially known as “orange” or “red” dwarfs, with our own star leaning more towards orange. Dwarf stars, such as our own, are quite stable, but are still prone to fluctuations in their luminosity over time.
Such fluctuations have occurred within living memory, and one particular period of dimming was noted by astronomers for many cycles prior to Mass Public Ascension… however, my own continued surveys suggest to me that this fluctuation may be part of a long Solar Cycle that ebbs and flows over a period of approximately 3200 Greater Cycles, or revolutions around the Sun. I imagine that the departed astronomers would be pleased to have an answer to this great Solar Conundrum, but I suppose their concerns now lay solely within the confines of the Void. Alas.
