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Layers
Spin Bolt wobble Outer shell ZeniTrams Cutaway Building heights Bolt Tower Traffic People Spaceplanes Day cycle Night haze Physics lines Spin arrows Borough outlines Labels
Cutaway slices the bulb along one fixed plane through the centre, so half the city and half of Bolt Tower are removed. Orbit around to see the cut face. With the outer shell off, its brass outline stays.
Key figures
Overall height 36 mi
Globe width 19.723 mi
Globe circumference 61.961 mi
Inner surface ≈1,185 sq mi
Populace 6,660,000
Density ≈5,620 / sq mi
Spin for 1 g 1 rev / 4.2 min (0.24 rpm)
Equator speed ≈875 mph
Bolt Tower ≈7° off-pole
Inner globe radius 9.71 mi
ZeniTram layer 9.72–9.86 mi
Shell Luminescent nanite substrate
Time & motion
East half day West half night
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Now
Live: the globe turns once every 4.2 minutes
Turn 1 of 457 this cycle
Wobble phase 0°
One clock drives everything: the spin, the wobble, and the light. Speeding it up speeds them together, so a cycle is always exactly 457 turns. Bolt wobble: the spin axis cones 7° once every 6 turns; the angle is fixed by how Bolt Tower’s mass is placed.
Earth orbit Hyper City rides a geosynchronous orbit: 22,236 mi up, one lap per sidereal day, so it keeps pace with Earth's turning. A flat, equatorial orbit would pin it over one spot on the equator. Tilting the orbit lets it swing north and south in a daily figure-8, from the equator up to the tilt's latitude, so each holiday gets its own orbit. A low tilt makes a small figure-8 (Diwali at 25°); a high one makes a big one (northern summer at 45°, which reaches over Paris). Drifting east or west between stops is cheap. Changing tilt is the expensive part, about 54 m/s per degree. It needs steady station-keeping against the Sun, the Moon and Earth's bulge. It is in free fall, so all its gravity comes from spin. Its base tip always points at Earth. A long body in orbit settles that way by itself, but the spinning inner globe is a gyroscope, so keeping the tip on Earth takes a gentle, steady torque.
Holiday tour all paths show until you pick one
Live schedule Show all
Polar tide illustrative The polar parks swap a little gravity back and forth as Bolt Tower drags the spin axis around its cone. Their glow pulses in step.
How gravity works here The inner globe spins once every 4.2 minutes about a horizontal axis, so riders are pressed against its inside surface. Felt gravity is 1 g on the spin equator and falls off as cos(latitude): about 0.44 g at the 64° park edge and near zero at the poles. That is why the towers crowd the equator and the poles are parks. Bolt Tower's Z-shape is a lopsided mass, so the spin axis cones around by about 7° once every six turns, giving the polar parks their gentle, opposite-phase tide. The outer shell turns the other way about the bulb's vertical axis, and the ZeniTrams roll between the two like the balls of a bearing.
Grid & boroughs Open the Atlas Show all
Every highway runs true to the poles. Ring highways are perfect loops that shorten toward the parks. Meridian highways run pole-ward to the Park Rings; the eight Grand Meridians (borough lines) carry on through the parks to the polar interchanges. Each block is two lots deep, so every building fronts an 8-lane highway. Vehicles use the highways; people walk on the nextways above them. Where Bolt Tower lands, the highways end at a traffic circle around its footing. The grid narrows toward the poles, so blocks hold five lots per row near the equator and two near the parks.
Architecture
ZeniTram loop
Skyport & ZeniTram Central