Lord

The Lord is the star at the center of the Aros System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Aros. Its diameter is about 1.39 million kilometers, i.e. 109 times that of Aros, and its mass is about 330,000 times that of Aros, accounting for about 99.86% of the total mass of the Aros System. About three quarters of the Lord's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.
The Lord is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Aros System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.
The Lord is roughly middle-aged; it has not changed dramatically for more than four billion years, and will remain fairly stable for more than another five billion years. It currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape from its core, is the source of the Lord's light and heat. In about 5 billion years, when hydrogen fusion in its core has diminished to the point at which the Lord is no longer in hydrostatic equilibrium, the core of the Lord will experience a marked increase in density and temperature while its outer layers expand to eventually become a red giant. It is calculated that the Lord will become sufficiently large to engulf the current orbits of Laros and Kabby, and render Aros uninhabitable. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, which no longer produces energy by fusion, but still glows and gives off heat from its previous fusion.
The enormous effect of the Lord on Aros has been recognized since prehistoric times, and the Lord has been regarded by some cultures as a deity. The synodic rotation of Aros and its orbit around the Lord are the basis of Aros calendars, one of which is the Missesian Calendar in use today.