Hello, I'm new to this forum and, to go right to the point, I created a fictional solar system for a tabletop RPG, appointing some characteristics that I want it to have, but I can't handle the physics to bring up the numbers - so I came here. To simplify it, this system only have 1 planet, and 1 star. 1. Here is what the star must look like to a person on the surface of the planet: 1a. Slightly smaller in appearance than the sun; 1b. Redder than the sun; 1c. Slightly less bright than the sun; 2. About the orbit: 2a. To complete an orbital period, the planet should take either 2.150 years or 25.800 years, the last one being preferable; 2b. Either way, each season should not surpass 10 years, ideally with 7 years. 3. About the planet: 3a. Identical to Earth (including 24h day/night). 3b. Posses a solo and dense ring around it (I have no idea if this is possible with smaller planets, but in regards to the story a ring is mandatory, so I'm abdicating on plausibility to keep this one, if necessary). In addition, the ring is always aligned right into the star's direction. 3c. Posses three natural satellites: one bigger than the moon (2x to 4x), one roughly the same size of the moon, and one smaller than the moon (4/5x to 2/5x). 4. About the star: 4a. Preferably, it should be larger than the sun – anywhere above 100 (one hundred) times larger in diameter will do, so I will set the ideal to 150 times larger in diameter. This information can be changed if it is impossible to achieve 1 and 2 with it; 4b. Must deliver roughly the same amount of anything the sun delivers to Earth (light, heat, radiation etc...) so that the fauna and flora of the planet keep similar to Earth’s. Given the info above, and fulfilling the criteria as best as reality permits, what I need to know is, summarizing: A -- How far away from the star should the planet stay, in au? B -- What is the minimum and maximum range of the habitable zone? C -- How much time will the planet take to complete one orbit around its star? D -- How long will each season last? E -- How would the ring be observable from the surface of the planet during day and night? Would it be clearly visible in the sky? Would it cast a shadow over the planet, or would the star's light simply overcome it? Obs.: I brought a one planet one star system to don't overcomplicate, but if the addition of more planets is necessary to make the first planet reach the criteria proposed, it can be done. Thank you for your time!