Far, far away in the universe (specifically, 542 million kiloparsecs from here), a galaxy stands as an enduring legacy of a long-extinct hyperadvanced alien civilization, high among the Kardashev scale. At the center is a supermassive black hole one trillion times as massive as our sun orbited by multitudes of giant stars, their lifespans artificially prolonged to last as long as red dwarves.
- First ring is a co-orbital of nine blue hypergiant binaries, each star is 56 times as wide, 250 times as massive and over six-and-a-half million times as bright as our sun.
- Second ring is a co-orbital of nine mixed binaries, each one a blue hypergiant (same as the first ring) orbited by a yellow hypergiant (1575 times as wide, 40 times as massive and 630,000 times as bright as our sun)
- Third ring is a co-orbital of nine yellow hypergiant binaries, all of which of the same parameters as on the second ring
- Fourth ring is a co-orbital of nine mixed binaries, each one a yellow hypergiant (same as the second and third rings) orbited by a red supergiant (2,069 times as wide, 20 times as massive and 589,000 times as bright as our sun)
- Fifth and final ring is a co-orbital of nine red supergiant binaries of the same parameters as the fourth ring
This arrangement creates a galactic habitable zone big enough to engulf our entire Milky Way. There are nine orbital rings within this habitable zone, each one consisting of a co-orbital of nine white dwarf stars, each one as wide as our moon, yet one-tenth of a percent as bright and 140% as massive as our sun, as per the Chandrasekhar Limit. Orbiting each of the white dwarves are nine orbital rings, and on each ring is a co-orbital of nine Earth-like planets, complete with its own large moon.
This is actually a benefit, as that since the white dwarves' purpose is strictly gravitational, sunlight comes only from all those oodles of massive stars orbiting the black hole. But then there is one issue that comes with orbiting a smaller but more massive star--the Roche Limit.
Basically speaking, the Roche Limit defines the minimum distance that one body can orbit a larger body without getting torn apart by gravity. Our sun's Roche Limit is 556,397 kilometers. How far would the Roche Limit of a star 140% as massive as our sun be?