Knowledge (XXG)

Great circle

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on the sphere, there is a unique great circle passing through both. (Every great circle through any point also passes through its antipodal point, so there are infinitely many great circles through two antipodal points.) The shorter of the two great-circle arcs between two distinct points on the
918: 866: 1199: 723: 540: 422: 1099:{\displaystyle {\frac {\sin \theta \cos \theta \phi '^{2}}{\sqrt {\theta '^{2}+\phi '^{2}\sin ^{2}\theta }}}={\frac {d}{dt}}{\frac {\theta '}{\sqrt {\theta '^{2}+\phi '^{2}\sin ^{2}\theta }}}.} 1372: 1254: 1301: 767: 1506: 1274: 563: 445: 222:, and is the intersection of the sphere with a plane not passing through its center. Small circles are the spherical-geometry analog of circles in Euclidean space. 1223: 910: 890: 759: 603: 583: 343: 319: 299: 1115: 615: 1428:
of the idealized earth is a great circle and any meridian and its opposite meridian form a great circle. Another great circle is the one that divides the
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coincides with the north pole. Any curve on the sphere that does not intersect either pole, except possibly at the endpoints, can be parametrized by
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To prove that the minor arc of a great circle is the shortest path connecting two points on the surface of a sphere, one can apply
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Loxodrome (Rhumb Line), Orthodrome (Great Circle), Great Ellipse and Geodetic Line (Geodesic) in Navigation
275: 322: 269: 184: 137: 31: 861:{\displaystyle {\frac {\sin ^{2}\theta \phi '}{\sqrt {\theta '^{2}+\phi '^{2}\sin ^{2}\theta }}}=C} 1556: 447:
is allowed to take on arbitrary real values. The infinitesimal arc length in these coordinates is
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of any great circle coincides with a diameter of the sphere, and therefore every great circle is
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by John Snyder with additional contributions by Jeff Bryant, Pratik Desai, and Carl Woll,
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Great Circle description, figures, and equations. Mathworld, Wolfram Research, Inc. c1999
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and a plane passing through its center. In higher dimensions, the great circles on the
718:{\displaystyle S=r\int _{a}^{b}{\sqrt {\theta '^{2}+\phi '^{2}\sin ^{2}\theta }}\,dt.} 1570: 1456: 196: 192: 1205:
Integrating both sides and considering the boundary condition, the real solution of
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A great circle is the largest circle that can be drawn on any given sphere. Any
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Every circle in Euclidean 3-space is a great circle of exactly one sphere.
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and if a great circle passes through a point it must pass through its
30:"Great Circle" redirects here. For the novel by Maggie Shipstead, see 1377:
which is a plane through the origin, i.e., the center of the sphere.
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From the first equation of these two, it can be obtained that
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integrates a function along all great circles of the sphere.
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A great circle divides the sphere in two equal hemispheres.
251:-sphere with 2-planes that pass through the origin in the 199:
formed by the two points and the center of the sphere.
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Consider the class of all regular paths from a point
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A great circle divides the earth into two 27:Spherical geometry analog of a straight line 57:(purple) through the center is called the 1352: 1330: 1315: 1287: 1281: 1261: 1230: 1210: 1180: 1161: 1155: 1130: 1117: 1078: 1067: 1049: 1030: 1015: 997: 986: 968: 951: 922: 920: 897: 877: 837: 826: 808: 778: 771: 769: 737: 705: 691: 680: 662: 652: 646: 641: 617: 590: 570: 550: 522: 508: 497: 479: 469: 455: 432: 353: 330: 306: 286: 191:on a sphere), and is proportional to the 1483:"Great Circle -- from Wolfram MathWorld" 155:of the sphere, so that great circles in 1473: 1064: 1046: 983: 965: 948: 823: 805: 677: 659: 494: 476: 1498: 1385:Some examples of great circles on the 232:bounded by a great circle is called a 1520:Weintrit, Adam; Kopcz, Piotr (2014). 7: 210:with the sphere and shares the same 25: 1557:Great Circles on Mercator's Chart 53:(black). The perpendicular line 1276:can be any value between 0 and 398: 376: 167:. For any pair of distinct non- 1561:Wolfram Demonstrations Project 748: 742: 628: 622: 392: 386: 370: 364: 236:: it is the intersection of a 1: 1551:Great Circle – from MathWorld 1417:), as well as on spheroidal 761:is minimized if and only if 264:Derivation of shortest paths 247:are the intersection of the 90:(blue) through the poles is 1305:Cartesian coordinate system 1296:{\displaystyle \theta _{0}} 912:-independent constant, and 1613: 1430:land and water hemispheres 1409:'s surface for air or sea 267: 159:are the natural analog of 29: 545:So the length of a curve 1249:{\displaystyle \phi '=0} 187:between the points (the 1526:. USA: CRC Press, Inc. 1415:is not a perfect sphere 1269:{\displaystyle \theta } 730:Euler–Lagrange equation 558:{\displaystyle \gamma } 151:of a great circle is a 1582:Spherical trigonometry 1368: 1297: 1270: 1250: 1219: 1195: 1100: 906: 886: 862: 755: 719: 609:of the curve given by 599: 579: 559: 536: 441: 418: 339: 315: 295: 276:calculus of variations 107: 99: 34:. For other uses, see 1487:mathworld.wolfram.com 1481:W., Weisstein, Eric. 1369: 1298: 1271: 1251: 1220: 1196: 1101: 907: 887: 863: 756: 720: 600: 580: 560: 537: 442: 440:{\displaystyle \phi } 419: 340: 323:spherical coordinates 316: 296: 270:Great-circle distance 185:great-circle distance 175:sphere is called the 105: 44: 1314: 1280: 1260: 1229: 1209: 1116: 919: 896: 876: 768: 736: 616: 589: 569: 549: 454: 431: 352: 329: 305: 285: 216:circle of the sphere 32:Great Circle (novel) 1587:Riemannian geometry 1577:Elementary geometry 651: 86:. Any great circle 1364: 1293: 1266: 1246: 1215: 1191: 1096: 902: 882: 858: 751: 715: 637: 595: 575: 555: 532: 437: 414: 335: 311: 291: 189:intrinsic distance 157:spherical geometry 108: 100: 1533:978-1-138-00004-9 1395:celestial equator 1391:celestial horizon 1218:{\displaystyle C} 1189: 1186: 1091: 1090: 1028: 1010: 1009: 905:{\displaystyle t} 885:{\displaystyle C} 850: 849: 754:{\displaystyle S} 728:According to the 703: 598:{\displaystyle q} 578:{\displaystyle p} 520: 338:{\displaystyle p} 314:{\displaystyle q} 301:to another point 294:{\displaystyle p} 45:The great circle 16:(Redirected from 1604: 1597:Spherical curves 1538: 1537: 1517: 1511: 1510: 1504: 1496: 1494: 1493: 1478: 1419:celestial bodies 1387:celestial sphere 1373: 1371: 1370: 1365: 1357: 1356: 1335: 1334: 1302: 1300: 1299: 1294: 1292: 1291: 1275: 1273: 1272: 1267: 1255: 1253: 1252: 1247: 1239: 1224: 1222: 1221: 1216: 1200: 1198: 1197: 1192: 1190: 1188: 1187: 1185: 1184: 1166: 1165: 1156: 1144: 1143: 1131: 1126: 1105: 1103: 1102: 1097: 1092: 1083: 1082: 1073: 1072: 1071: 1055: 1054: 1053: 1040: 1039: 1031: 1029: 1027: 1016: 1011: 1002: 1001: 992: 991: 990: 974: 973: 972: 959: 958: 957: 956: 955: 923: 911: 909: 908: 903: 891: 889: 888: 883: 867: 865: 864: 859: 851: 842: 841: 832: 831: 830: 814: 813: 812: 799: 798: 797: 783: 782: 772: 760: 758: 757: 752: 724: 722: 721: 716: 704: 696: 695: 686: 685: 684: 668: 667: 666: 653: 650: 645: 604: 602: 601: 596: 584: 582: 581: 576: 564: 562: 561: 556: 541: 539: 538: 533: 521: 513: 512: 503: 502: 501: 485: 484: 483: 470: 446: 444: 443: 438: 423: 421: 420: 415: 344: 342: 341: 336: 320: 318: 317: 312: 300: 298: 297: 292: 259: 97: 89: 85: 77: 76: 68: 64: 56: 52: 48: 36:The Great Circle 21: 1612: 1611: 1607: 1606: 1605: 1603: 1602: 1601: 1567: 1566: 1547: 1542: 1541: 1534: 1519: 1518: 1514: 1497: 1491: 1489: 1480: 1479: 1475: 1470: 1453: 1438:antipodal point 1383: 1348: 1326: 1312: 1311: 1283: 1278: 1277: 1258: 1257: 1232: 1227: 1226: 1225:is zero. Thus, 1207: 1206: 1176: 1157: 1145: 1136: 1132: 1119: 1114: 1113: 1074: 1063: 1059: 1045: 1041: 1032: 1020: 993: 982: 978: 964: 960: 947: 943: 924: 917: 916: 894: 893: 874: 873: 833: 822: 818: 804: 800: 790: 774: 773: 766: 765: 734: 733: 687: 676: 672: 658: 654: 614: 613: 587: 586: 567: 566: 547: 546: 504: 493: 489: 475: 471: 452: 451: 429: 428: 350: 349: 327: 326: 303: 302: 283: 282: 272: 266: 255: 253:Euclidean space 165:Euclidean space 138:passing through 95: 87: 83: 78:(red), are the 74: 70: 66: 62: 54: 50: 46: 39: 28: 23: 22: 15: 12: 11: 5: 1610: 1608: 1600: 1599: 1594: 1589: 1584: 1579: 1569: 1568: 1565: 1564: 1554: 1546: 1545:External links 1543: 1540: 1539: 1532: 1512: 1472: 1471: 1469: 1466: 1465: 1464: 1459: 1452: 1449: 1445:Funk transform 1382: 1379: 1375: 1374: 1363: 1360: 1355: 1351: 1347: 1344: 1341: 1338: 1333: 1329: 1325: 1322: 1319: 1290: 1286: 1265: 1245: 1242: 1238: 1235: 1214: 1203: 1202: 1183: 1179: 1175: 1172: 1169: 1164: 1160: 1154: 1151: 1148: 1142: 1139: 1135: 1129: 1125: 1122: 1107: 1106: 1095: 1089: 1086: 1081: 1077: 1070: 1066: 1062: 1058: 1052: 1048: 1044: 1038: 1035: 1026: 1023: 1019: 1014: 1008: 1005: 1000: 996: 989: 985: 981: 977: 971: 967: 963: 954: 950: 946: 942: 939: 936: 933: 930: 927: 901: 881: 870: 869: 857: 854: 848: 845: 840: 836: 829: 825: 821: 817: 811: 807: 803: 796: 793: 789: 786: 781: 777: 750: 747: 744: 741: 726: 725: 714: 711: 708: 702: 699: 694: 690: 683: 679: 675: 671: 665: 661: 657: 649: 644: 640: 636: 633: 630: 627: 624: 621: 594: 574: 554: 543: 542: 531: 528: 525: 519: 516: 511: 507: 500: 496: 492: 488: 482: 478: 474: 468: 465: 462: 459: 436: 425: 424: 413: 410: 407: 404: 401: 397: 394: 391: 388: 385: 382: 379: 375: 372: 369: 366: 363: 360: 357: 334: 310: 290: 265: 262: 161:straight lines 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 1609: 1598: 1595: 1593: 1590: 1588: 1585: 1583: 1580: 1578: 1575: 1574: 1572: 1562: 1558: 1555: 1552: 1549: 1548: 1544: 1535: 1529: 1525: 1524: 1516: 1513: 1508: 1502: 1488: 1484: 1477: 1474: 1467: 1463: 1460: 1458: 1457:Great ellipse 1455: 1454: 1450: 1448: 1446: 1441: 1439: 1435: 1431: 1427: 1422: 1420: 1416: 1413:(although it 1412: 1408: 1404: 1400: 1396: 1392: 1388: 1380: 1378: 1361: 1358: 1353: 1349: 1345: 1342: 1339: 1336: 1331: 1327: 1323: 1320: 1317: 1310: 1309: 1308: 1306: 1288: 1284: 1263: 1243: 1240: 1236: 1233: 1212: 1181: 1177: 1173: 1170: 1167: 1162: 1158: 1152: 1149: 1146: 1140: 1137: 1133: 1127: 1123: 1120: 1112: 1111: 1110: 1093: 1087: 1084: 1079: 1075: 1068: 1060: 1056: 1050: 1042: 1036: 1033: 1024: 1021: 1017: 1012: 1006: 1003: 998: 994: 987: 979: 975: 969: 961: 952: 944: 940: 937: 934: 931: 928: 925: 915: 914: 913: 899: 879: 855: 852: 846: 843: 838: 834: 827: 819: 815: 809: 801: 794: 791: 787: 784: 779: 775: 764: 763: 762: 745: 739: 731: 712: 709: 706: 700: 697: 692: 688: 681: 673: 669: 663: 655: 647: 642: 638: 634: 631: 625: 619: 612: 611: 610: 608: 592: 572: 552: 529: 526: 523: 517: 514: 509: 505: 498: 490: 486: 480: 472: 466: 463: 460: 457: 450: 449: 448: 434: 411: 408: 405: 402: 399: 395: 389: 383: 380: 377: 373: 367: 361: 358: 355: 348: 347: 346: 332: 324: 308: 288: 279: 277: 271: 263: 261: 258: 254: 250: 246: 244: 239: 235: 231: 226: 223: 221: 217: 213: 209: 205: 200: 198: 197:central angle 194: 190: 186: 182: 178: 173: 170: 166: 162: 158: 154: 150: 145: 143: 140:the sphere's 139: 136: 132: 128: 125: 121: 117: 113: 104: 93: 81: 73: 60: 43: 37: 33: 19: 18:Great circles 1522: 1515: 1490:. Retrieved 1486: 1476: 1442: 1423: 1389:include the 1384: 1381:Applications 1376: 1204: 1108: 871: 727: 544: 426: 321:. Introduce 280: 273: 256: 248: 242: 233: 227: 224: 220:small circle 218:is called a 214:. Any other 201: 176: 146: 142:center point 127:intersection 119: 116:great circle 115: 109: 91: 79: 71: 58: 1434:hemispheres 112:mathematics 1571:Categories 1492:2022-09-30 1468:References 1462:Rhumb line 1411:navigation 1397:, and the 1307:, this is 607:functional 268:See also: 234:great disk 208:concentric 181:arc length 120:orthodrome 1403:geodesics 1350:ϕ 1346:⁡ 1337:− 1328:ϕ 1324:⁡ 1285:θ 1264:θ 1234:ϕ 1174:− 1171:θ 1168:⁡ 1153:θ 1150:⁡ 1138:θ 1121:ϕ 1088:θ 1085:⁡ 1061:ϕ 1043:θ 1034:θ 1007:θ 1004:⁡ 980:ϕ 962:θ 945:ϕ 941:θ 938:⁡ 932:θ 929:⁡ 847:θ 844:⁡ 820:ϕ 802:θ 792:ϕ 788:θ 785:⁡ 746:γ 701:θ 698:⁡ 674:ϕ 656:θ 639:∫ 626:γ 553:γ 518:θ 515:⁡ 491:ϕ 473:θ 435:ϕ 427:provided 409:≤ 403:≤ 384:ϕ 378:ϕ 362:θ 356:θ 177:minor arc 169:antipodal 92:secondary 1501:cite web 1451:See also 1399:ecliptic 1237:′ 1141:′ 1124:′ 1065:′ 1047:′ 1037:′ 984:′ 966:′ 949:′ 824:′ 806:′ 795:′ 678:′ 660:′ 495:′ 477:′ 325:so that 204:diameter 153:geodesic 124:circular 1592:Circles 1426:equator 1405:on the 278:to it. 245:-sphere 195:of the 193:measure 183:is the 122:is the 1530:  1393:, the 872:where 212:radius 172:points 133:and a 131:sphere 1407:Earth 892:is a 605:is a 565:from 135:plane 129:of a 80:poles 75:' 1528:ISBN 1507:link 1443:The 1424:The 1256:and 238:ball 230:disk 228:The 147:Any 114:, a 69:and 59:axis 1343:cos 1321:sin 1159:sin 1147:sin 1076:sin 995:sin 935:cos 926:sin 835:sin 776:sin 689:sin 585:to 506:sin 163:in 149:arc 118:or 110:In 94:to 82:of 61:of 1573:: 1503:}} 1499:{{ 1485:. 1440:. 1421:. 732:, 260:. 144:. 1563:. 1536:. 1509:) 1495:. 1362:0 1359:= 1354:0 1340:y 1332:0 1318:x 1289:0 1244:0 1241:= 1213:C 1201:. 1182:2 1178:C 1163:2 1134:C 1128:= 1094:. 1080:2 1069:2 1057:+ 1051:2 1025:t 1022:d 1018:d 1013:= 999:2 988:2 976:+ 970:2 953:2 900:t 880:C 868:, 856:C 853:= 839:2 828:2 816:+ 810:2 780:2 749:] 743:[ 740:S 713:. 710:t 707:d 693:2 682:2 670:+ 664:2 648:b 643:a 635:r 632:= 629:] 623:[ 620:S 593:q 573:p 530:. 527:t 524:d 510:2 499:2 487:+ 481:2 467:r 464:= 461:s 458:d 412:b 406:t 400:a 396:, 393:) 390:t 387:( 381:= 374:, 371:) 368:t 365:( 359:= 333:p 309:q 289:p 257:R 249:n 243:n 98:. 96:g 88:s 84:g 72:P 67:P 63:g 55:a 51:O 47:g 38:. 20:)

Index

Great circles
Great Circle (novel)
The Great Circle


mathematics
circular
intersection
sphere
plane
passing through
center point
arc
geodesic
spherical geometry
straight lines
Euclidean space
antipodal
points
arc length
great-circle distance
intrinsic distance
measure
central angle
diameter
concentric
radius
circle of the sphere
small circle
disk

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