The closest planet to Sol is One and little is known about it
The next closest planet to Sol is Two and little is known about it.
The third closest planet to Sol is Three, and is naturally habitable to homo sapiens without any need for terraforming. The climate and geography are very similar to Earth That Was, but sufficient history has been lost such that whether Three actually is Earth That Was or simply a similar planet is unknown.
Three has one moon which is called Luna. Luna is tidally locked to Three, and has two scientific-oriented bases which are limited to scientists of various fields, their families, and support staff. Unlike other planets and moons in the system, there is no tourism industry, permanent population, or government on Luna.
The two bases, one on each side of the moon, one facing Three and one facing away, are connected by a high-speed, equatorial train.
The seventh planet in the Cups system is a large gas giant that is uninhabitable, known as Seven, but has many moons, most of which have a high enough gravity to comfortably support human life.
Innermost to outermost moons:
Vili and Ve,
Largest to smallest moons:
Vili and Ve,
Nanna and Vali are the only two moons with permanent populations.
Nanna is the largest moon of Seven also has the largest permanent human colony of all the moons of Seven, and has the fourth smallest orbit. It has several dome colonies around it's surface and spins on its axis once every 46 earth hours. Since Nanna is so far from Sol, it is Seven that provides the most light and occupies the greatest percentage of the sky. Visitors to Nanna and Vidar who are unnaccostomed to Seven hanging over them often find themselves unconsciously hunched over in response to Seven hanging in the sky.
Vidar is a pleasure moon, with domes dedicated to various forms of entertainment. It also has a deep mine system that fully penetrates the solid core of the moon and features special zero gravity entertainment. There are actually two parallel inner core spheres, one for tourists and one exclusively for permanent residents of Nanna.
Ull is the second smallest moon of seven with the most elliptical and inclined orbit. At it's furthest from Seven, it swings slightly outside Sif's orbit (without overlapping). It houses a scientific base dedicated to early detection of meteors, and tracking and indexing asteroids.
Vali is the second most distant moon from Seven and caters to interstellar corporations as a headquarters and tax haven. It's entire economy is funded by banking and legal services.
Sif is a captured asteroid that is unusually rich in rare ores. In terms of asteroids, it is unusually large, but in terms of moons, it is rather small.