fuzzyworld

tower / interior-flight / files / content / geography.json

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geography.json

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1de9dc7c 2026-09-07 Pavel Safronov1{
2 "version": 1,
3 "$comment": [
4 "Authored geography for Tower. This file is the SOURCE OF TRUTH for terrain.",
5 "`npm run terrain` reads it and generates the height map, the colour map, and a",
6 "seed world.json of places for the app.",
7 "",
8 "Coordinates are canon (design.md §1.7): theta in radians around the cylinder,",
9 "z in metres from the sun cap. Elevation is metres ABOVE the base shell radius —",
10 "i.e. inward, toward the axis — because in Tower 'up' means closer to the spin",
11 "axis. All relief is engineered; a bare cylinder is an equipotential with no",
12 "slope anywhere (design.md §1.9.3).",
13 "",
14 "All names are PROVISIONAL. Every feature carries \"provisionalName\": true until",
15 "the author replaces it."
16 ],
17 "datum": {
18 "radiusM": 50000,
19 "lengthM": 540000,
20 "circumferenceM": 314159.27,
21 "primeMeridian": "theta = 0 runs through the capital"
22 },
23 "compass": {
24 "sunward": "-z, toward the sun cap",
25 "deepward": "+z, toward the far cap",
26 "spinward": "+theta, the direction of rotation",
27 "antispinward": "-theta — everything that falls leans this way (§1.9.2), so a waterfall is a compass"
28 },
29 "render": {
30 "gridWidth": 2048,
31 "gridHeight": 1192,
32 "metresPerPixel": 263.7,
9a621732 2026-09-08 Pavel Safronov33 "minHeightM": -560,
5a57ebae 2026-09-07 Pavel Safronov34 "maxHeightM": 4400,
35 "$heightRangeNote": "The working range of terrain-height.png, not a limit on the world. Browsers decode a 16-bit PNG to 8 bits, so the app reads 256 levels across this span — keeping it tight to the terrain that exists is what makes the interior view's ground smooth. Below zero is real: lake and sea floors are cut beneath the datum.",
1de9dc7c 2026-09-07 Pavel Safronov36 "mapThetaOrigin": 3.14159265,
37 "$mapThetaOriginNote": "Where the unrolled map is cut. With no slats there is no empty theta to hide the seam in (D-013), so the cut goes opposite the capital — the antimeridian principle, applied to habitation instead of geology.",
38 "snowlineM": 3000,
39 "hillshade": {
40 "azimuthDeg": 315,
41 "altitudeDeg": 42,
42 "strength": 0.55
43 },
44 "corridor": {
45 "$comment": "A close view of the developed region. At world scale the canyon is six pixels wide.",
46 "width": 2048,
47 "height": 1020,
48 "zFrom": 40000,
49 "zTo": 305000,
50 "thetaFrom": -0.6,
51 "thetaTo": 0.72
52 }
53 },
54 "hydrology": {
55 "$comment": "The loop of D-018. Sized so the catchment supports the flow at a plausible rainfall.",
56 "meanFlowM3S": 392,
57 "catchmentKM2": 9800,
58 "impliedPrecipitationMMYr": 1262,
59 "sourceElevationM": 1900,
60 "mouthElevationM": 160,
61 "liftHeadM": 1780,
e27aaf20 2026-09-08 Pavel Safronov62 "pumpPowerW": 6850000000,
1de9dc7c 2026-09-07 Pavel Safronov63 "pumpPowerPercentOfBudget": 0.0126,
64 "closure": "made-weather",
65 "closureNote": "Tower evaporates The Deep and snows it onto the range; the tarns are the top of the loop. Four rivers descend, three are defeated by the ridges and gather along their front, and all of it leaves through The Narrows as one river.",
66 "trunk": "the-long-water",
67 "tributaries": [
68 "westwall-water",
69 "sisters-water",
70 "eastwall-water"
71 ]
72 },
73 "features": [
74 {
75 "id": "the-plain",
76 "name": "The Open Ground",
77 "provisionalName": true,
78 "kind": "region",
79 "biome": "plain",
80 "geometry": {
81 "type": "whole-surface"
82 },
83 "relief": {
84 "op": "base",
85 "baseM": 60,
86 "noiseAmpM": 260,
87 "noiseScaleM": 78000,
88 "octaves": 5,
89 "detailAmpM": 45,
9a621732 2026-09-08 Pavel Safronov90 "detailScaleM": 12000,
91 "microAmpM": 26,
92 "microScaleM": 1500,
93 "$microNote": "The octave the raster can just about hold: 1.5 km features at 264 m per pixel. Below this the PNG cannot carry it and the interior view has to invent it."
1de9dc7c 2026-09-07 Pavel Safronov94 },
95 "notes": "Everything outside the developed corridor. Deliberately gentle — this is shaped ground that nobody has bothered to make dramatic."
96 },
97 {
98 "id": "sunward-sea",
99 "name": "The Sunward Sea",
100 "provisionalName": true,
101 "kind": "lake",
102 "biome": "water",
103 "geometry": {
104 "type": "band",
105 "ring": true,
106 "zFrom": 0,
107 "zTo": 42000
108 },
109 "waterLevelM": 90,
110 "relief": {
111 "op": "flood",
112 "depthM": 420,
113 "edgeM": 16000,
114 "warpM": 6000
115 },
116 "notes": "At the foot of the sun cap. Gravity on a cap is tangent to it, so water cannot rest there — it runs to the rim and pools. This ocean is not designed; it is what happens."
117 },
118 {
119 "id": "deepward-sea",
120 "name": "The Deepward Sea",
121 "provisionalName": true,
122 "kind": "lake",
123 "biome": "water",
124 "geometry": {
125 "type": "band",
126 "ring": true,
127 "zFrom": 496000,
128 "zTo": 540000
129 },
130 "waterLevelM": 90,
131 "relief": {
132 "op": "flood",
133 "depthM": 420,
134 "edgeM": 16000,
135 "warpM": 6000
136 },
137 "notes": "The same at the far cap, and the larger of the two. A 314 km shoreline with a 50 km cliff behind it, and the only windows in the world at its foot (§1.4)."
138 },
15d933c9 2026-09-07 Pavel Safronov139 {
140 "id": "sun-cap",
141 "name": "The Sun Cap",
142 "provisionalName": true,
143 "kind": "landmark",
144 "geometry": {
145 "type": "point",
e27aaf20 2026-09-08 Pavel Safronov146 "theta": 0,
15d933c9 2026-09-07 Pavel Safronov147 "z": 0
148 },
149 "notes": "The sunward end of the world, and one of only two views out (§1.4). A cap is a wall, not a floor: gravity there points radially outward, tangent to its surface, so nothing rests on it. Fifty kilometres of vertical cliff with its windows at the base, and the beam entering through a 3.2 km aperture at its centre."
150 },
151 {
152 "id": "far-cap",
153 "name": "The Far Cap",
154 "provisionalName": true,
155 "kind": "landmark",
156 "geometry": {
157 "type": "point",
e27aaf20 2026-09-08 Pavel Safronov158 "theta": 0,
15d933c9 2026-09-07 Pavel Safronov159 "z": 540000
160 },
161 "notes": "The deepward end, 540 km away, standing over The Deepward Sea. Its windows look along the spin axis — which is the celestial pole — so the stars do not sweep past but turn about a fixed centre, one revolution every 7 min 29 s. The only moving sky anyone in Tower ever sees."
162 },
1de9dc7c 2026-09-07 Pavel Safronov163 {
164 "id": "snowcrown",
165 "name": "Snowcrown",
166 "provisionalName": true,
167 "kind": "mountain",
168 "biome": "alpine",
169 "geometry": {
170 "type": "point",
171 "theta": 0.3,
172 "z": 88000
173 },
174 "elevationM": 4300,
175 "relief": {
176 "op": "dome",
177 "radiusThetaM": 30000,
178 "radiusZM": 33000,
179 "heightM": 4300,
180 "falloff": 1.7,
181 "ridgedAmp": 0.55,
182 "ridgedScaleM": 15000,
183 "warpM": 9000
184 }
185 },
186 {
187 "id": "the-sisters",
188 "name": "The Sisters",
189 "provisionalName": true,
190 "kind": "mountain",
191 "biome": "alpine",
192 "geometry": {
193 "type": "point",
194 "theta": -0.52,
195 "z": 94000
196 },
197 "elevationM": 3650,
198 "relief": {
199 "op": "dome",
200 "radiusThetaM": 26000,
201 "radiusZM": 28000,
202 "heightM": 3650,
203 "falloff": 1.7,
204 "ridgedAmp": 0.55,
205 "ridgedScaleM": 15000,
206 "warpM": 9000
207 }
208 },
209 {
210 "id": "westwall",
211 "name": "Westwall",
212 "provisionalName": true,
213 "kind": "mountain",
214 "biome": "alpine",
215 "geometry": {
216 "type": "point",
217 "theta": -1.1,
218 "z": 86000
219 },
220 "elevationM": 3400,
221 "relief": {
222 "op": "dome",
223 "radiusThetaM": 24000,
224 "radiusZM": 26000,
225 "heightM": 3400,
226 "falloff": 1.7,
227 "ridgedAmp": 0.55,
228 "ridgedScaleM": 15000,
229 "warpM": 9000
230 }
231 },
232 {
233 "id": "eastwall",
234 "name": "Eastwall",
235 "provisionalName": true,
236 "kind": "mountain",
237 "biome": "alpine",
238 "geometry": {
239 "type": "point",
240 "theta": 0.98,
241 "z": 92000
242 },
243 "elevationM": 3550,
244 "relief": {
245 "op": "dome",
246 "radiusThetaM": 25000,
247 "radiusZM": 27000,
248 "heightM": 3550,
249 "falloff": 1.7,
250 "ridgedAmp": 0.55,
251 "ridgedScaleM": 15000,
252 "warpM": 9000
253 }
254 },
e27aaf20 2026-09-08 Pavel Safronov255 {
256 "id": "the-girdle",
257 "name": "The Girdle",
258 "provisionalName": true,
259 "kind": "region",
260 "biome": "alpine",
261 "geometry": {
262 "type": "band",
263 "ring": true,
264 "z": 90000
265 },
266 "relief": {
267 "op": "ridge",
268 "blend": "max",
269 "heightM": 2900,
270 "widthZM": 17000,
271 "warpM": 12000,
272 "ridgedAmp": 0.6,
273 "ridgedScaleM": 14000
274 },
275 "notes": "The range does not stop at Eastwall. It carries on round the far side of the world and closes on itself — a ring of peaks at z 90 km, unbroken except where the rivers cut it. Snowcrown, The Sisters, Westwall and Eastwall are the named high points of it, not a range of their own; the rest is unwalked. Rings the world 86 km sunward of the three low ridges, and is the reason every river on this half of Tower runs deepward."
276 },
1de9dc7c 2026-09-07 Pavel Safronov277 {
278 "id": "hollow-tarn",
279 "name": "Hollow Tarn",
280 "provisionalName": true,
281 "kind": "lake",
282 "biome": "water",
283 "geometry": {
284 "type": "ellipse",
285 "theta": 0.22,
286 "z": 100000,
287 "radiusThetaM": 2000,
288 "radiusZM": 2400
289 },
290 "relief": {
291 "op": "tarn",
292 "depthM": 190,
293 "rimM": 120,
294 "fillFraction": 0.6
295 },
296 "notes": "The Long Water's source and the top of the world's water loop. Every litre in Tower passes through here."
297 },
298 {
299 "id": "sisters-tarn",
300 "name": "Sisters Tarn",
301 "provisionalName": true,
302 "kind": "lake",
303 "biome": "water",
304 "geometry": {
305 "type": "ellipse",
306 "theta": -0.47,
307 "z": 104000,
308 "radiusThetaM": 2000,
309 "radiusZM": 2400
310 },
311 "relief": {
312 "op": "tarn",
313 "depthM": 190,
314 "rimM": 120,
315 "fillFraction": 0.6
316 },
317 "notes": "Largest of the high lakes. A ski settlement stands on its deepward shore."
318 },
319 {
320 "id": "west-tarn",
321 "name": "Cold Tarn",
322 "provisionalName": true,
323 "kind": "lake",
324 "biome": "water",
325 "geometry": {
326 "type": "ellipse",
327 "theta": -1.05,
328 "z": 98000,
329 "radiusThetaM": 2000,
330 "radiusZM": 2400
331 },
332 "relief": {
333 "op": "tarn",
334 "depthM": 190,
335 "rimM": 120,
336 "fillFraction": 0.6
337 }
338 },
339 {
340 "id": "east-tarn",
341 "name": "Long Tarn",
342 "provisionalName": true,
343 "kind": "lake",
344 "biome": "water",
345 "geometry": {
346 "type": "ellipse",
347 "theta": 0.94,
348 "z": 103000,
349 "radiusThetaM": 2000,
350 "radiusZM": 2400
351 },
352 "relief": {
353 "op": "tarn",
354 "depthM": 190,
355 "rimM": 120,
356 "fillFraction": 0.6
357 }
358 },
359 {
360 "id": "the-dry-reach",
361 "name": "The Dry Reach",
362 "provisionalName": true,
363 "kind": "desert",
364 "biome": "desert",
365 "geometry": {
366 "type": "band",
367 "ring": true,
368 "zFrom": 148000,
369 "zTo": 218000
370 },
371 "relief": {
372 "op": "plateau",
373 "heightM": 780,
374 "edgeM": 20000,
375 "noiseAmpM": 90,
376 "noiseScaleM": 9000,
377 "warpM": 13000,
378 "warpScaleM": 40000
379 },
380 "notes": "Rings the world. On a cylinder you cannot go around a band — a ringed desert is an absolute barrier, which no Earth desert ever is. 70 km deep, 22,000 km², 13% of the world. Dry because Tower withholds rain here, not because terrain shades it."
381 },
382 {
383 "id": "first-ridge",
384 "name": "First Ridge",
385 "provisionalName": true,
386 "kind": "region",
387 "biome": "desert",
388 "geometry": {
389 "type": "band",
390 "ring": true,
391 "z": 176000
392 },
393 "relief": {
394 "op": "ridge",
395 "heightM": 260,
396 "widthZM": 7000,
397 "warpM": 5000
398 },
399 "notes": "Rings the world with its two siblings: three concentric walls across Tower's waist. Every drainage off the range is turned by them. Only one river was here before they were raised and only that one still cuts through — The Narrows is the single breach in all three."
400 },
401 {
402 "id": "second-ridge",
403 "name": "Second Ridge",
404 "provisionalName": true,
405 "kind": "region",
406 "biome": "desert",
407 "geometry": {
408 "type": "band",
409 "ring": true,
410 "z": 190000
411 },
412 "relief": {
413 "op": "ridge",
414 "heightM": 300,
415 "widthZM": 6500,
416 "warpM": 5000
417 }
418 },
419 {
420 "id": "third-ridge",
421 "name": "Third Ridge",
422 "provisionalName": true,
423 "kind": "region",
424 "biome": "desert",
425 "geometry": {
426 "type": "band",
427 "ring": true,
428 "z": 203000
429 },
430 "relief": {
431 "op": "ridge",
432 "heightM": 240,
433 "widthZM": 7500,
434 "warpM": 5000
435 }
436 },
437 {
438 "id": "westwall-water",
439 "name": "Westwall Water",
440 "provisionalName": true,
441 "kind": "river",
442 "geometry": {
443 "type": "polyline",
444 "points": [
445 [
446 -1.06,
447 104000
448 ],
449 [
450 -1.02,
451 118000
452 ],
453 [
454 -0.92,
455 132000
456 ],
457 [
458 -0.8,
459 144000
460 ],
461 [
462 -0.66,
463 152000
464 ],
465 [
466 -0.52,
467 155500
468 ],
469 [
470 -0.4,
471 158500
472 ],
473 [
474 -0.28,
475 157500
476 ],
477 [
478 -0.16,
479 160000
480 ],
481 [
482 -0.06,
483 161000
484 ],
485 [
486 0.062,
487 162000
488 ]
489 ]
490 },
491 "profileM": [
492 1980,
493 1560,
494 1180,
495 930,
496 830,
497 790,
498 762,
499 752,
500 730,
501 715,
502 700
503 ],
504 "relief": {
505 "op": "carve",
506 "reaches": [
507 {
508 "toIndex": 99,
509 "valleyWidthM": 2600,
510 "channelWidthM": 280,
511 "depthM": 220,
512 "wallExponent": 1.3,
513 "shoulderM": 2600
514 }
515 ]
516 },
517 "notes": "Turned by First Ridge and forced to run spinward along its front, gathering the others."
518 },
519 {
520 "id": "sisters-water",
521 "name": "Sisters Water",
522 "provisionalName": true,
523 "kind": "river",
524 "geometry": {
525 "type": "polyline",
526 "points": [
527 [
528 -0.47,
529 110000
530 ],
531 [
532 -0.45,
533 124000
534 ],
535 [
536 -0.4,
537 138000
538 ],
539 [
540 -0.33,
541 148000
542 ],
543 [
544 -0.24,
545 154000
546 ],
547 [
548 -0.14,
549 157500
550 ],
551 [
552 -0.04,
553 160000
554 ],
555 [
556 0.062,
557 162000
558 ]
559 ]
560 },
561 "profileM": [
562 1900,
563 1500,
564 1180,
565 950,
566 835,
567 780,
568 735,
569 700
570 ],
571 "relief": {
572 "op": "carve",
573 "reaches": [
574 {
575 "toIndex": 99,
576 "valleyWidthM": 2600,
577 "channelWidthM": 280,
578 "depthM": 220,
579 "wallExponent": 1.3,
580 "shoulderM": 2600
581 }
582 ]
583 }
584 },
585 {
586 "id": "eastwall-water",
587 "name": "Eastwall Water",
588 "provisionalName": true,
589 "kind": "river",
590 "geometry": {
591 "type": "polyline",
592 "points": [
593 [
594 0.95,
595 108000
596 ],
597 [
598 0.92,
599 122000
600 ],
601 [
602 0.86,
603 134000
604 ],
605 [
606 0.78,
607 145000
608 ],
609 [
610 0.66,
611 152000
612 ],
613 [
614 0.54,
615 155000
616 ],
617 [
618 0.42,
619 158000
620 ],
621 [
622 0.3,
623 157000
624 ],
625 [
626 0.2,
627 159500
628 ],
629 [
630 0.12,
631 161000
632 ],
633 [
634 0.062,
635 162000
636 ]
637 ]
638 },
639 "profileM": [
640 1960,
641 1580,
642 1250,
643 970,
644 850,
645 805,
646 775,
647 762,
648 738,
649 716,
650 700
651 ],
652 "relief": {
653 "op": "carve",
654 "reaches": [
655 {
656 "toIndex": 99,
657 "valleyWidthM": 2600,
658 "channelWidthM": 280,
659 "depthM": 220,
660 "wallExponent": 1.3,
661 "shoulderM": 2600
662 }
663 ]
664 },
665 "notes": "Runs antispinward along the ridge front. It and Westwall Water meet head-on at the gap."
666 },
667 {
668 "id": "the-long-water",
669 "name": "The Long Water",
670 "provisionalName": true,
671 "kind": "river",
672 "geometry": {
673 "type": "polyline",
674 "points": [
675 [
676 0.22,
677 100000
678 ],
679 [
680 0.195,
681 112000
682 ],
683 [
684 0.17,
685 126000
686 ],
687 [
688 0.14,
689 140000
690 ],
691 [
692 0.1,
693 152000
694 ],
695 [
696 0.062,
697 162000
698 ],
699 [
700 0.03,
701 170000
702 ],
703 [
704 -0.01,
705 178000
706 ],
707 [
708 0.015,
709 186000
710 ],
711 [
712 -0.02,
713 194000
714 ],
715 [
716 0.005,
717 201000
718 ],
719 [
720 -0.015,
721 208000
722 ],
723 [
724 0.01,
725 216000
726 ],
727 [
728 0.048,
729 226000
730 ],
731 [
732 0.086,
733 236000
734 ],
735 [
736 0.12,
737 246000
738 ]
739 ]
740 },
741 "profileM": [
742 1900,
743 1560,
744 1240,
745 940,
746 800,
747 700,
748 640,
749 580,
750 520,
751 460,
752 415,
753 370,
754 320,
755 250,
756 180,
757 124
758 ],
759 "relief": {
760 "op": "carve",
761 "reaches": [
762 {
763 "$reach": "mountain valley",
764 "toIndex": 6,
765 "valleyWidthM": 4200,
766 "channelWidthM": 280,
767 "depthM": 300,
768 "wallExponent": 1.25,
769 "shoulderM": 3500
770 },
771 {
772 "$reach": "The Narrows",
773 "toIndex": 12,
774 "valleyWidthM": 3200,
775 "channelWidthM": 260,
776 "depthM": 480,
777 "wallExponent": 0.5,
778 "shoulderM": 1100
779 },
780 {
781 "$reach": "forest reach",
782 "toIndex": 17,
783 "valleyWidthM": 5200,
784 "channelWidthM": 340,
785 "depthM": 80,
786 "wallExponent": 1.7,
787 "shoulderM": 6500
788 }
789 ]
790 },
791 "notes": "Trunk of the whole system. Above the gap it is one of four; below it carries all of them — about 392 m³/s off a 9,800 km² range. Zero Coriolis on its axial reaches (§1.9.1); the tributaries running along the ridge front are the only circumferential water in the world, and they weigh fractionally more or less for it (§1.9.2)."
792 },
793 {
794 "id": "the-narrows",
795 "name": "The Narrows",
796 "provisionalName": true,
797 "kind": "canyon",
798 "geometry": {
799 "type": "polyline",
800 "points": [
801 [
802 0.03,
803 170000
804 ],
805 [
806 -0.01,
807 178000
808 ],
809 [
810 0.015,
811 186000
812 ],
813 [
814 -0.02,
815 194000
816 ],
817 [
818 0.005,
819 201000
820 ],
821 [
822 -0.015,
823 208000
824 ]
825 ]
826 },
827 "depthM": 420,
828 "lengthM": 40000,
829 "notes": "The only breach in all three ridges, and therefore the only route along the axis of the world. 40 km long, rim ~1,000 m, up to 480 m deep. Whoever holds The Narrows holds Tower. Antecedent, exactly like the Yakima crossing the Manastash and Umtanum."
830 },
831 {
832 "id": "greatwood",
833 "name": "Greatwood",
834 "provisionalName": true,
835 "kind": "forest",
836 "biome": "forest",
837 "geometry": {
838 "type": "band",
839 "ring": true,
840 "zFrom": 214000,
841 "zTo": 430000
842 },
843 "relief": {
844 "op": "plateau",
845 "heightM": 250,
846 "edgeM": 30000,
847 "noiseAmpM": 70,
848 "noiseScaleM": 15000,
849 "warpM": 18000,
850 "warpScaleM": 55000
851 },
852 "notes": "A forest belt ringing the world deepward of the desert. Tower rains here on purpose."
853 },
854 {
855 "id": "the-deep",
856 "name": "The Deep",
857 "provisionalName": true,
858 "kind": "lake",
859 "biome": "water",
860 "geometry": {
861 "type": "rect",
862 "zFrom": 248000,
863 "zTo": 402000,
864 "thetaFrom": 0.06,
865 "thetaTo": 0.7
866 },
867 "waterLevelM": 120,
868 "relief": {
869 "op": "flood",
870 "depthM": 330,
871 "edgeM": 11000,
872 "warpM": 7000,
873 "warpScaleM": 34000
874 },
875 "notes": "Long down the axis and narrow around it, which is the whole point: you cross it the SHORT way, around theta, and the far shore rides 2.6 km above your eye. 154 km long, 32 km wide. Fed by The Long Water at its sunward head. Its heat capacity is the world's flywheel (§1.9.4)."
876 },
877 {
878 "id": "the-capital",
879 "name": "The Capital",
880 "provisionalName": true,
881 "kind": "city",
882 "geometry": {
883 "type": "point",
884 "theta": 0.02,
885 "z": 270000
886 },
887 "elevationM": 175,
888 "notes": "z = 270 km, the axial midpoint — the only centre a cylinder has. On The Deep's antispinward shore, so the city looks across 32 km of water at a far shore standing 2.6 km up in its sky. Deepward of The Narrows: it sits behind the world's only gate."
889 },
890 {
891 "id": "the-spindle",
892 "name": "The Spindle",
893 "provisionalName": true,
894 "kind": "tower",
895 "geometry": {
896 "type": "point",
897 "theta": 0.02,
898 "z": 271500
899 },
900 "elevationM": 175,
901 "heightM": 3200,
902 "notes": "The tall tower. At 3.2 km its top sits in 0.94 g and its sway period differs from its base. Height is a free choice — see the open question in design.md §1.11."
903 },
904 {
905 "id": "sisters-station",
906 "name": "Sisters Station",
907 "provisionalName": true,
908 "kind": "city",
909 "geometry": {
910 "type": "point",
911 "theta": -0.47,
912 "z": 110500
913 },
914 "elevationM": 2100,
915 "notes": "Ski settlement above Sisters Tarn. Runs facing antispinward are the fast ones: a skier descending against the spin loses up to 8.6% of their weight at speed, and the effect grows as they accelerate. Prograde runs grip harder instead. Every slope in Tower has a handedness; no Earth mountain does."
916 },
917 {
918 "id": "hollow-station",
919 "name": "Hollow Station",
920 "provisionalName": true,
921 "kind": "city",
922 "geometry": {
923 "type": "point",
924 "theta": 0.235,
925 "z": 102000
926 },
927 "elevationM": 2100
928 }
929 ]
930}