The suite towers are grouped and named according to the objects and their classifications in our Solar System. The -Z Towers on the right are the Inner Solar System, Rocky.
The +Z Towers on the left are the Outer Solar System, Gaseous. 433 Suites Total in 5 Towers on each Hub
  Mercury and Jupiter Towers - 9 Suites, each.
  Venus and Saturn Towers - 21 Suites, each.
  Earth and Uranus Towers - 39 Suites, each.
  Mars and Neptune Towers - 61 Suites, each.
  Asteroid Belt and Kuiper Belt Towers - 86 Suites, each.
1 Executive StarSuite at the Top of Kuiper Belt Tower
1 EarthView Bar/Restaurant at the Top of Asteroid Belt Tower
8 Domed Observation Lounges, 1 on the Top of each of the other four Towers
2 Observation Loop Platforms on Rocky and Gaseous Core Tubes
3 Sports/Recreation Facility Rings
1 Hydroponics Lab Ring

Why is it Shaped Like This?

Energy conservation. Gravity Gradient will passively stabilize the spacecraft if there is a high aspect ratio to its form. An orbiting body that is on station for any length of time will begin to rotate, such that the long axis aligns radially from the parent body. Gravity decreases by inverse square of distance, so portions of the spacecraft that are closer to the parent body are more attracted by it. Minimal amounts of attitude control energy will then be required to maintain this orientation. Next: Final Approach

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