20:
525:
549:
501:
537:
513:
122:. The celestial equator is defined to be infinitely distant (since it is on the celestial sphere); thus, the ends of the semicircle always intersect the horizon due east and due west, regardless of the observer's position on Earth. At the
130:, the celestial equator is a uniform arc or circle because the observer is only finitely far from the plane of the celestial equator, but infinitely far from the celestial equator itself.
261:
Over thousands of years, the orientation of Earth's equator and thus the constellations the celestial equator passes through will change due to
569:
579:
574:
379:
468:
118:, the point directly overhead. As the observer moves north (or south), the celestial equator tilts towards the opposite
295:
76:
589:
491:
371:
339:
191:
140:(reach the meridian) highest near the equator. The celestial equator currently passes through these
248:
172:
100:
316:
472:
243:
167:
152:
220:
201:
177:
423:"New model of Mars surface irradiation for the climate simulation chamber 'Artificial Mars'"
352:
434:
348:
156:
80:
8:
553:
469:"Equal length of day and night on Saturn: the start of spring in the northern hemisphere"
211:
133:
438:
136:
near the celestial equator appear above the horizon from most places on earth, but they
541:
529:
450:
72:
99:), but has varied from about 22.0° to 24.5° over the past 5 million years due to
454:
422:
396:
375:
123:
584:
505:
442:
280:
262:
96:
56:
268:
Celestial bodies other than Earth also have similarly defined celestial equators.
91:, the celestial equator is currently inclined by about 23.44° with respect to the
181:
285:
446:
563:
141:
40:
420:
337:
Berger, A.L. (1976). "Obliquity and
Precession for the Last 5000000 Years".
517:
421:
Tarasashvili MV, Sabashvili ShA, Tsereteli SL, Aleksidze NG (26 Mar 2013).
52:
290:
196:
137:
84:
60:
126:, the celestial equator coincides with the astronomical horizon. At all
111:
88:
28:
232:
19:
127:
92:
36:
24:
23:
The celestial equator is currently inclined by about 23.44° to the
237:
226:
206:
119:
107:
64:
115:
368:
The
Amateur Astronomer's Introduction to the Celestial Sphere
162:
68:
512:
79:. In other words, the celestial equator is an abstract
489:
27:
plane. The image shows the relations between Earth's
258:
These are the most globally visible constellations.
561:
16:Projection of Earth's equator out into space
18:
562:
365:
336:
110:visualizes the celestial equator as a
427:International Journal of Astrobiology
223:(contains the first point of Libra)
13:
14:
601:
547:
535:
523:
511:
499:
394:
106:An observer standing on Earth's
83:of the terrestrial equator into
570:Astronomical coordinate systems
580:Technical factors of astrology
461:
414:
388:
359:
330:
309:
1:
302:
71:. By extension, it is also a
575:Dynamics of the Solar System
296:Rotation around a fixed axis
146:
77:equatorial coordinate system
7:
397:"Map of the Constellations"
274:
10:
606:
372:Cambridge University Press
340:Astronomy and Astrophysics
159:above its southern border)
148:
447:10.1017/S1473550413000062
217:
188:
149:
366:Millar, William (2006).
473:German Aerospace Center
353:1976A&A....51..127B
44:
22:
157:first point of Aries
134:Astronomical objects
114:passing through the
103:from other planets.
439:2013IJAsB..12..161T
317:"Celestial Equator"
73:plane of reference
45:
590:Planes (geometry)
381:978-0-521-67123-1
256:
255:
87:. Due to Earth's
55:of the imaginary
49:celestial equator
597:
552:
551:
550:
540:
539:
538:
528:
527:
526:
516:
515:
504:
503:
502:
495:
484:
483:
481:
479:
465:
459:
458:
418:
412:
411:
409:
407:
392:
386:
385:
363:
357:
356:
334:
328:
327:
325:
323:
313:
281:Axial precession
263:axial precession
147:
57:celestial sphere
605:
604:
600:
599:
598:
596:
595:
594:
560:
559:
558:
548:
546:
536:
534:
524:
522:
510:
500:
498:
490:
488:
487:
477:
475:
467:
466:
462:
419:
415:
405:
403:
395:Ford, Dominic.
393:
389:
382:
364:
360:
335:
331:
321:
319:
315:
314:
310:
305:
277:
271:
17:
12:
11:
5:
603:
593:
592:
587:
582:
577:
572:
557:
556:
544:
532:
520:
508:
486:
485:
460:
433:(2): 161–170.
413:
401:in-the-sky.org
387:
380:
358:
347:(1): 127–135.
329:
307:
306:
304:
301:
300:
299:
293:
288:
286:Celestial pole
283:
276:
273:
254:
253:
252:
251:
246:
241:
235:
230:
224:
216:
215:
214:
209:
204:
199:
194:
187:
186:
185:
175:
170:
165:
160:
155:(contains the
142:constellations
95:(the plane of
15:
9:
6:
4:
3:
2:
602:
591:
588:
586:
583:
581:
578:
576:
573:
571:
568:
567:
565:
555:
545:
543:
533:
531:
521:
519:
514:
509:
507:
497:
496:
493:
474:
470:
464:
456:
452:
448:
444:
440:
436:
432:
428:
424:
417:
402:
398:
391:
383:
377:
373:
369:
362:
354:
350:
346:
342:
341:
333:
318:
312:
308:
297:
294:
292:
289:
287:
284:
282:
279:
278:
272:
269:
266:
264:
259:
250:
247:
245:
242:
239:
236:
234:
231:
228:
225:
222:
219:
218:
213:
210:
208:
205:
203:
200:
198:
195:
193:
190:
189:
183:
179:
176:
174:
171:
169:
166:
164:
161:
158:
154:
151:
150:
145:
143:
139:
135:
131:
129:
125:
121:
117:
113:
109:
104:
102:
98:
97:Earth's orbit
94:
90:
86:
82:
78:
74:
70:
66:
62:
58:
54:
50:
42:
41:orbital plane
38:
37:rotation axis
34:
30:
26:
21:
554:Solar System
476:. Retrieved
463:
430:
426:
416:
404:. Retrieved
400:
390:
367:
361:
344:
338:
332:
320:. Retrieved
311:
270:
267:
260:
257:
182:Orion's belt
132:
105:
101:perturbation
53:great circle
48:
46:
32:
542:Outer space
530:Spaceflight
291:Declination
197:Canis Minor
85:outer space
564:Categories
303:References
112:semicircle
89:axial tilt
81:projection
61:same plane
29:axial tilt
506:Astronomy
455:120041831
233:Ophiuchus
192:Monoceros
138:culminate
128:latitudes
33:obliquity
322:5 August
275:See also
249:Aquarius
173:Eridanus
93:ecliptic
25:ecliptic
585:Circles
492:Portals
435:Bibcode
349:Bibcode
240:(cauda)
238:Serpens
229:(caput)
227:Serpens
207:Sextans
120:horizon
108:equator
75:in the
65:equator
63:as the
59:on the
51:is the
453:
378:
298:(pole)
244:Aquila
180:(near
168:Taurus
153:Pisces
116:zenith
39:, and
518:Stars
478:1 Feb
451:S2CID
406:1 Feb
221:Virgo
202:Hydra
178:Orion
163:Cetus
124:poles
69:Earth
480:2021
408:2021
376:ISBN
324:2011
47:The
31:(or
443:doi
212:Leo
67:of
35:),
566::
471:.
449:.
441:.
431:12
429:.
425:.
399:.
374:.
370:.
345:51
343:.
265:.
144::
494::
482:.
457:.
445::
437::
410:.
384:.
355:.
351::
326:.
184:)
43:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.