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Lunar month

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164: 1819: 1169: 666: 36: 435:, the Moon must move a little further to reach the new position having the same angular distance from the Sun, appearing to move with respect to the stars since the previous month. Consequently, at 27 days, 7 hours, 43 minutes and 11.5 seconds, the sidereal month is about 2.2 days shorter than the synodic month. Thus, about 13.37 sidereal months, but about 12.37 synodic months, occur in a 1496: 2124:
In medieval times, the part of the Moon's orbit south of the ecliptic was known as the 'dragon' (which devoured the Moon during eclipses) and from this we get the terminology 'dragon's head' for the ascending node and 'dragon's tail' for the descending node. … The periods between successive nodes
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the numerical conversion factor then becomes 2 × B1 × B1 ÷ B2 = 2 × 1,296,000. This would give a linear term in days change (of the period) per day, which is also an inconvenient unit: for change per year multiply by a factor 365.25, and for change per century multiply by a factor 36,525.
1814:{\displaystyle Q={1 \over A'}={1 \over A_{1}+(2\times A_{2}\times T)}={1 \over A_{1}}\times {1 \over 1+(2\times {A_{2} \over A_{1}}\times T)}={1 \over A_{1}}\times (1-2\times {A_{2} \over A_{1}}\times T)={1 \over A_{1}}-(2\times {A_{2} \over (A_{1}\times A_{1})}\times T)} 1482: 474:
may vary from about 29.27 to about 29.83 days. The average duration in modern times is 29.53059 days with up to seven hours variation about the mean in any given year. (which gives a mean synodic month as 29.53059 days or
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This article is about the definitions of a 'month' that are mainly of significance in astronomy. For other definitions, including a description of a month in the calendars of different cultures around the world, see
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is based on the amount of time between perceived rotations of the sun around the earth (based on the Greek word τροπή meaning "turn"), the tropical month is the average time between corresponding
2349:
Elements of Astronomy: Accompanied with Numerous Illustrations, a Colored Representations of the Solar, Stellar, and Nebular Spectra, and Celestial Charts of the Northern and Southern Hemisphere
304:, a "lunar month" traditionally meant exactly 28 days or four weeks, thus a contract for 12 months ran for exactly 48 weeks. In the United Kingdom, the lunar month was formally replaced by the 730:
approximates an ellipse rather than a circle. However, the orientation (as well as the shape) of this orbit is not fixed. In particular, the position of the extreme points (the line of the
1933: 898:
to that in which the Moon is orbiting Earth, one rotation every 18.6 years. Therefore, the Moon returns to the same node slightly earlier than it returns to meet the same reference star.
592:. It is also the average time between successive moments when the moon crosses from the southern celestial hemisphere to the northern (or vice versa), or successive crossing of a given 746:) in about 3,233 days (8.85 years). It takes the Moon longer to return to the same apsis because it has moved ahead during one revolution. This longer period is called the 2011: 853:
about 5.14° with respect to the ecliptic plane. The line of intersection of these planes passes through the two points at which the Moon's orbit crosses the ecliptic plane: the
408:, is the average period of the Moon's orbit with respect to the line joining the Sun and Earth: 29 (Earth) days, 12 hours, 44 minutes and 2.9 seconds. This is the period of the 572:
days (27 d 7 h 43 min 11.6 s).This type of month has been observed among cultures in the Middle East, India, and China in the following way: they divided the sky into 27 or 28
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westward, which means the nodes gradually rotate around Earth. As a result, the time it takes the Moon to return to the same node is shorter than a sidereal month, lasting
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as the Moon is orbiting the Earth, one revolution in about 8.85 years. Therefore, the Moon takes a little longer to return to perigee than to return to the same star.
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Regardless of the culture, all lunar calendar months approximate the mean length of the synodic month, the average period the Moon takes to cycle through
470:. The same is true (to an even larger extent) for the Moon's orbit around Earth. Because of these two variations in angular rate, the actual time between 769:), whose extent, duration, and appearance (whether total or annular) depend on the exact apparent diameter of the Moon. The apparent diameter of the 546: 1151:
Apart from the long term (millennial) drift in these values, all these periods vary continually around their mean values because of the complex
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calendar, widely used in the Indian subcontinent. In India, the month from conjunction to conjunction is divided into thirty parts known as
1144:, which follows the somewhat unpredictable rotation of the Earth, and progressively accumulates a difference with ephemeris time called 525:
corresponds to 1 January AD 2000). The duration of synodic months in ancient and medieval history is itself a topic of scholarly study.
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The nodical month is the time in which the Moon accomplishes a revolution with respect to her nodes, the line of which is also movable.
777:, which is the beat period of the synodic and anomalistic month, as well as the period after which the apsides point to the Sun again. 2620: 345:
Most of the following types of lunar month, except the distinction between the sidereal and tropical months, were first recognized in
1216: 713: 119: 2601: 1295: 2681: 163: 2486: 1194: 838:. A solar or lunar eclipse is possible only when the Moon is at or near either of the two points where its orbit crosses the 691: 57: 2181: 2125:
has, over time, been termed the dracontic, draconic and draconitic month, the words deriving from the Greek for 'dragon'.
484: 100: 2353: 1190: 687: 72: 53: 2531:
Chapront-Touzé, M; Chapront, J (1988). "ELP 2000-85: a semi-analytical lunar ephemeris adequate for historical times".
412:, because the Moon's appearance depends on the position of the Moon with respect to the Sun as seen from Earth. Due to 2652: 1179: 676: 212:, the lunar month began on the day when the waning moon could no longer be seen just before sunrise. Others run from 171:
as it cycles through its phases, as seen from the Northern Hemisphere. The apparent wobbling of the Moon is known as
2729: 2635: 2498:"A new determination of lunar orbital parameters, precession constant and tidal acceleration from LLR measurements" 1879: 1842:
1 revolution (rev) is 360 × 60 × 60" = 1,296,000"; to convert the unit of the velocity to revolutions/day, divide A
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The draconic or nodical month is the average interval between two successive transits of the Moon through the same
620: 227:. Calendars count integer days, so months may be 29 or 30 days in length, in some regular or irregular sequence. 79: 2246:, p. 577: For convenience, it is common to speak of a lunar year of twelve synodic months, or 354.36707 days. 1198: 1183: 695: 680: 46: 1251:
to the sidereal angular velocity, we get the angular velocity w.r.t. the Equinox of the Date: its period is the
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of 36,525 days. For calendrical calculations, one would probably use days measured in the time scale of
86: 1137: 313: 1964: 2719: 2672: 2668: 431:
While the Moon is orbiting Earth, Earth is progressing in its orbit around the Sun. After completing its
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motion around the Sun, the Moon does not yet finish a synodic cycle until it has reached the point in
2639: 2568: 2540: 2509: 604: 316:(Schedule 1 read with sections 5 and 23 and with Schedule 2 paragraph 4(1)(a)) and its predecessors. 2664:
Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac
2497: 2060: 1145: 931: 850: 2584: 2325: 2045: 2036:= 94,672,800,000 × −6.8498 ÷ (1,602,961,601.0312 × 1,602,961,601.0312) = −0.00000025238 days/cy. 743: 655: 597: 436: 404:, meaning "pertaining to a synod, i.e., a meeting"; in this case, of the Sun and the Moon), also 149: 922:. The Moon completes one orbit around Earth every 27.3 days (a sidereal month), but due to 2616: 2415: 2256: 2224: 949: 942: 927: 895: 887: days (27 d 5 h 5 min 35.8 s). The line of nodes of the Moon's orbit 758: 727: 600:. The moon rises at the North Pole once every tropical month, and likewise at the South Pole. 534: 518: 421: 209: 937:
This table lists the average lengths of five types of astronomical lunar month, derived from
2576: 2544: 2517: 2513: 2357: 2075: 2070: 2050: 1477:{\displaystyle \operatorname {d} \!A/\operatorname {d} \!t=A'=A_{1}+(2\times A_{2}\times T)} 1248: 1122: 956: 923: 888: 873: 797: 793: 651: 612: 538: 459: 443: 205: 761:
of the Moon varies with this period, so this type has some relevance for the prediction of
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A more precise figure of the average duration may be derived for a specific date using the
2734: 2055: 1243:
W1 is the ecliptic longitude of the Moon w.r.t. the fixed ICRS equinox: its period is the
781: 774: 593: 220: 93: 2643: 2572: 2441: 2065: 1141: 1118: 839: 558: 451: 447: 385: 358: 325: 305: 141: 780:
An anomalistic month is longer than a sidereal month because the perigee moves in the
2713: 2588: 2462: 639: 608: 585: 573: 455: 420:(sunrise to sunrise on the Moon) equals the time that the Moon takes to complete one 413: 2396: 1234: 894:
A draconic month is shorter than a sidereal month because the nodes precess in the
843: 801: 553:
because it is the time it takes the Moon to return to a similar position among the
480: 346: 228: 219:
Yet others use calculation, of varying degrees of sophistication, for example, the
185: 2437: 2347: 416:, the same hemisphere of the Moon always faces the Earth and thus the length of a 2522: 2488:
A Treatise on the Limitations of Actions at Law and Suits in Equity and Admiralty
1168: 907: 766: 665: 624: 542: 425: 409: 368: 339: 189: 35: 2580: 1283: 877: 865: 831: 576:, one for each day of the month, identified by the prominent star(s) in them. 301: 232: 17: 2553: 603:
It is customary to specify positions of celestial bodies with respect to the
915: 770: 463: 417: 364: 213: 172: 160:. The precise definition varies, especially for the beginning of the month. 157: 2326:"Questions and Answers: What does the period "tropical month" represent?" 941:. These are not constant, so a first-order (linear) approximation of the 911: 616: 471: 467: 374: 224: 197: 153: 458:
of Earth's progression around the Sun varies during the year. Thus, the
231:
are prominent, and calculated with great precision in the ancient Hindu
952: 835: 762: 735: 589: 1129: 869: 827: 739: 193: 2496:
Chapront, Jean; Chapront-Touzé, Michelle; Francou, George (2002).
731: 238: 162: 134: 2466: 2202: 2200: 2198: 2196: 2194: 554: 168: 2032:= 47,336,400,000 ÷ 1,602,961,601.0312 = 29.530588860986 days; C 204:
with the Sun one or two days before that evening (e.g., in the
1862:
is then the period (in days/revolution) at the epoch J2000.0.
1275:
is the elongation of the Moon from the Sun: its period is the
1162: 919: 876:
of the Earth–Moon system, the plane of the Moon's orbit
757: days (27 d 13 h 18 min 33.2 s). The 659: 308:
for deeds and other written contracts by section 61(a) of the
29: 2632:
From Eudoxus to Einstein: a history of mathematical astronomy
1238: 938: 249:
is between 19 and 26 hours long. The date is named after the
1375:{\displaystyle A=A_{0}+(A_{1}\times T)+(A_{2}\times T^{2})} 1126: 291:
is associated with two consecutive days. This is known as
2667:. London: Her Majesty's Stationery Office. 1961. pp.  619:. Therefore, it takes the Moon less time to return to an 2554:"Ancient and Medieval Values for the Mean Synodic Month" 1839:
is expressed in cy/" which is a very inconvenient unit.
1229:
The periods are derived from polynomial expressions for
634:
days (27 d 7 h 43 min 4.7 s), is commonly known as the
2704:. The Royal Astronomical Society of Canada. p. 14. 2491:. Boston: Charles C Little and James Brown. p. 52. 2379: 2377: 2273: 2308: 2306: 1967: 1882: 1499: 1399: 1388:
in centuries (cy) is 36,525 days from epoch J2000.0.
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Example for synodic month, from Delaunay's argument
399: 60:. Unsourced material may be challenged and removed. 2683:Explanatory Supplement to the Astronomical Almanac 2005: 1927: 1813: 1476: 1374: 1136:is centuries since the epoch (2000), expressed in 842:; i.e., the satellite is at or near either of its 1415: 1403: 891:360° in about 6,798 days (18.6 years). 330:There are several types of lunar month. The term 2330:Journal of the British Astronomical Association 2020:: D′ = 1602961601.0312 − 2 × 6.8498 × T "/cy; A 1267:is the argument of latitude: its period is the 373:"Lunation" redirects here. For the number, see 1873:= 1,296,000 × 36,525 = 1,728,962,010,000,000. 1391:The angular velocity is the first derivative: 849:The orbit of the Moon lies in a plane that is 1928:{\displaystyle A_{2}\div (A_{1}\times A_{1})} 1155:of the Sun and planets affecting its motion. 8: 918:, last quarter) and back again: 29–30 2416:"Length of the Synodic Month: 2001 to 2100" 2257:"Length of the Synodic Month: 2001 to 2100" 2223:. Richmond, VA: Willmann-Bell. p. 23. 1239:Chapront, Chapront-Touzé & Francou 2002 1197:. Unsourced material may be challenged and 939:Chapront, Chapront-Touzé & Francou 2002 694:. Unsourced material may be challenged and 292: 286: 280: 274: 268: 262: 256: 250: 244: 236: 2285: 2243: 2206: 2107:in July. In 2004 the variations were from 1491:) is the inverse of the angular velocity: 2567:(114). Science History Publications: 65. 2521: 2297: 1991: 1978: 1966: 1916: 1903: 1887: 1881: 1790: 1777: 1763: 1757: 1737: 1728: 1708: 1698: 1692: 1666: 1657: 1634: 1624: 1618: 1597: 1586: 1577: 1556: 1534: 1524: 1506: 1498: 1459: 1437: 1407: 1398: 1363: 1350: 1325: 1309: 1297: 1217:Learn how and when to remove this message 714:Learn how and when to remove this message 615:, this point moves back slowly along the 200:first becomes visible, at evening, after 120:Learn how and when to remove this message 2099:In 2001, the synodic months varied from 1850:= 1,296,000 × 36,525 = 47,336,400,000; C 961: 285:may 'stall' as well, that is – the same 2657:. Chicago: University of Chicago Press. 2138: 2092: 1259:is the mean anomaly: its period is the 547:International Celestial Reference Frame 338:because it is the cycle of the visible 2383: 2157: 2145: 623:of 0° than to the same point amid the 196:traditions, the month starts when the 2598:Astrophysical Data: Planets and Stars 2221:Astronomical formulae for calculators 2006:{\displaystyle P=C_{1}-C_{2}\times T} 326:Orbital period § Related periods 312:and for post-1850 legislation by the 7: 2680:Seidelmann, P. Kenneth, ed. (1992). 2561:Journal for the History of Astronomy 2312: 2274:Chapront-Touzé & Chapront (1988) 1195:adding citations to reliable sources 1117:In this table, time is expressed in 872:exerted by the Sun's gravity on the 692:adding citations to reliable sources 58:adding citations to reliable sources 2169: 432: 148:is the time between two successive 1412: 1400: 834:and eat the Sun or Moon during an 485:Chapront-Touzé and Chapront (1988) 335: 25: 627:. This slightly shorter period, 27:Time between successive new moons 2485:Angell, Joseph Kinnicut (1846). 1167: 664: 34: 2630:Linton, Christopher M. (2004). 2463:"Eclipses and the Moon's Orbit" 2436:Fraser Cain (24 October 2008). 2184:, volume 27: "Time", paragraph 537:as defined with respect to the 375:New moon § Lunation number 45:needs additional citations for 2654:The Calendars of Ancient Egypt 1922: 1896: 1808: 1796: 1770: 1748: 1722: 1677: 1648: 1609: 1568: 1543: 1471: 1446: 1369: 1343: 1337: 1318: 1282:Derivation of a period from a 1255:month (which is rarely used). 511:= (JD − 2451545.0)/36525 267:may jump. This case is called 1: 1824:ignoring higher-order terms. 930:where the Sun is in the same 750:and has an average length of 490:29.5305888531 + 0.00000021621 261:is shorter than the day, the 225:ecclesiastical lunar calendar 2700:Bishop, Roy L., ed. (1991). 2502:Astronomy & Astrophysics 2346:Lockyer, Sir Norman (1870). 1940:= 2 × 1,296,000 × 36,525 × A 255:ruling at sunrise. When the 2651:Parker, Richard A. (1950). 2615:. Oxford University Press. 2609:Law, Jonathan, ed. (1983). 2552:Goldstein, Bernard (2003). 613:precession of the equinoxes 400: 293: 287: 281: 275: 269: 263: 257: 251: 245: 237: 2751: 2636:Cambridge University Press 2581:10.1177/002182860303400104 2533:Astronomy and Astrophysics 2523:10.1051/0004-6361:20020420 2182:Halsbury's Laws of England 1237:, as listed in Table 4 of 791: 649: 372: 362: 356: 347:Babylonian lunar astronomy 323: 131: 2024:= 1602961601.0312 "/cy; A 389: 638:by analogy with Earth's 424:, returning to the same 310:Law of Property Act 1925 2545:1988A&A...190..342C 2514:2002A&A...387..700C 2401:Encyclopedia Britannica 1835:in "/cy; so the result 607:(Sun's location at the 314:Interpretation Act 1978 2596:Lang, Kenneth (2012). 2007: 1929: 1815: 1478: 1376: 1125:) with days of 86,400 955:(1 January 2000 12:00 830:, said to live in the 611:). Because of Earth's 562: 549:; ICRF) is known as a 334:usually refers to the 176: 2354:American Book Company 2008: 1930: 1816: 1479: 1377: 1247:month. If we add the 826:refers to a mythical 477:29 d 12 h 44 min 3 s) 433:§ Sidereal month 357:Further information: 166: 2219:Meeus, Jean (2002). 2209:, pp. 107, 488. 1965: 1880: 1865:For rev/day divide A 1497: 1397: 1296: 1191:improve this section 688:improve this section 605:First Point of Aries 54:improve this article 2702:Observer's handbook 2644:2004fete.book.....L 2612:A Dictionary of Law 2573:2003JHA....34...65G 2061:Babylonian calendar 814:is also known as a 198:young crescent moon 2263:. 8 November 2019. 2046:Lunisolar calendar 2003: 1925: 1811: 1474: 1372: 1249:rate of precession 1233:arguments used in 896:opposite direction 744:apsidal precession 656:Apsidal precession 621:ecliptic longitude 598:ecliptic longitude 533:The period of the 446:around the Sun is 422:orbit around Earth 340:phases of the Moon 177: 152:of the same type: 2730:Orbit of the Moon 2324:John Guy Porter, 2286:Seidelmann (1992) 2244:Seidelmann (1992) 2230:978-0-9433-9674-3 2207:Supplement (1961) 1800: 1743: 1714: 1672: 1652: 1640: 1592: 1572: 1519: 1227: 1226: 1219: 1112: 1111: 932:relative position 914:, first quarter, 878:gradually rotates 868:. Because of the 759:apparent diameter 748:anomalistic month 742:), rotates once ( 724: 723: 716: 646:Anomalistic month 519:Julian day number 462:is faster nearer 398: 167:Animation of the 130: 129: 122: 104: 16:(Redirected from 2742: 2705: 2687: 2676: 2658: 2647: 2626: 2605: 2592: 2558: 2548: 2527: 2525: 2492: 2471: 2470: 2459: 2453: 2452: 2450: 2448: 2433: 2427: 2426: 2424: 2422: 2411: 2405: 2404: 2397:"Draconic month" 2393: 2387: 2381: 2372: 2371: 2366: 2364: 2343: 2337: 2322: 2316: 2310: 2301: 2295: 2289: 2283: 2277: 2271: 2265: 2264: 2253: 2247: 2241: 2235: 2234: 2216: 2210: 2204: 2189: 2179: 2173: 2167: 2161: 2155: 2149: 2148:, pp. 9–23. 2143: 2126: 2122: 2116: 2114: 2113:29 d 10 h 34 min 2110: 2109:29 d 15 h 35 min 2106: 2102: 2101:29 d 19 h 14 min 2097: 2076:Tibetan calendar 2071:Islamic calendar 2051:Chinese calendar 2028:= −6.8498"/cy; C 2012: 2010: 2009: 2004: 1996: 1995: 1983: 1982: 1934: 1932: 1931: 1926: 1921: 1920: 1908: 1907: 1892: 1891: 1831:in "/cy ; A 1820: 1818: 1817: 1812: 1801: 1799: 1795: 1794: 1782: 1781: 1768: 1767: 1758: 1744: 1742: 1741: 1729: 1715: 1713: 1712: 1703: 1702: 1693: 1673: 1671: 1670: 1658: 1653: 1651: 1641: 1639: 1638: 1629: 1628: 1619: 1598: 1593: 1591: 1590: 1578: 1573: 1571: 1561: 1560: 1539: 1538: 1525: 1520: 1518: 1507: 1483: 1481: 1480: 1475: 1464: 1463: 1442: 1441: 1429: 1411: 1381: 1379: 1378: 1373: 1368: 1367: 1355: 1354: 1330: 1329: 1314: 1313: 1286:for an argument 1222: 1215: 1211: 1208: 1202: 1171: 1163: 1138:Julian centuries 1123:Terrestrial Time 1121:(more precisely 1104: 1102: 1096: 1095: 1092: 1076: 1074: 1068: 1067: 1064: 1048: 1046: 1040: 1039: 1036: 1020: 1018: 1012: 1011: 1008: 992: 990: 984: 983: 980: 962: 886: 885: 874:angular momentum 812:draconitic month 798:Nodal precession 794:Lunar precession 773:varies with the 756: 755: 719: 712: 708: 705: 699: 668: 660: 652:Lunar precession 633: 632: 571: 570: 539:celestial sphere 524: 516: 512: 505: 501: 499: 478: 466:and slower near 460:angular velocity 403: 393: 391: 296: 290: 284: 278: 272: 266: 260: 254: 248: 242: 206:Islamic calendar 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 2750: 2749: 2745: 2744: 2743: 2741: 2740: 2739: 2725:Lunar calendars 2710: 2709: 2708: 2699: 2695: 2693:Further reading 2690: 2679: 2661: 2650: 2629: 2623: 2608: 2595: 2556: 2551: 2530: 2495: 2484: 2480: 2475: 2474: 2461: 2460: 2456: 2446: 2444: 2435: 2434: 2430: 2420: 2418: 2414:Espenak, Fred. 2413: 2412: 2408: 2395: 2394: 2390: 2382: 2375: 2362: 2360: 2345: 2344: 2340: 2323: 2319: 2311: 2304: 2296: 2292: 2284: 2280: 2272: 2268: 2261:astropixels.com 2255: 2254: 2250: 2242: 2238: 2231: 2218: 2217: 2213: 2205: 2192: 2180: 2176: 2168: 2164: 2156: 2152: 2144: 2140: 2135: 2130: 2129: 2123: 2119: 2112: 2108: 2105:29 d 7 h 11 min 2104: 2100: 2098: 2094: 2089: 2084: 2056:Hebrew calendar 2042: 2035: 2031: 2027: 2023: 1987: 1974: 1963: 1962: 1951: 1947: 1943: 1939: 1912: 1899: 1883: 1878: 1877: 1872: 1868: 1861: 1857: 1853: 1849: 1845: 1834: 1830: 1786: 1773: 1769: 1759: 1733: 1704: 1694: 1662: 1630: 1620: 1602: 1582: 1552: 1530: 1529: 1511: 1495: 1494: 1455: 1433: 1422: 1395: 1394: 1359: 1346: 1321: 1305: 1294: 1293: 1223: 1212: 1206: 1203: 1188: 1172: 1161: 1153:orbital effects 1100: 1098: 1093: 1090: 1088: 1072: 1070: 1065: 1062: 1060: 1044: 1042: 1037: 1034: 1032: 1016: 1014: 1009: 1006: 1004: 988: 986: 981: 978: 976: 968:Length in days 924:Earth's orbital 904: 883: 881: 859:descending node 804: 790: 775:full moon cycle 753: 751: 720: 709: 703: 700: 685: 669: 658: 648: 630: 628: 594:right ascension 582: 568: 566: 531: 522: 514: 507: 497: 495: 489: 488: 476: 378: 371: 361: 355: 328: 322: 279:. Conversely a 221:Hebrew calendar 182: 142:lunar calendars 138: 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 2748: 2746: 2738: 2737: 2732: 2727: 2722: 2712: 2711: 2707: 2706: 2696: 2694: 2691: 2689: 2688: 2686:. p. 576. 2677: 2659: 2648: 2627: 2622:978-0198802525 2621: 2606: 2593: 2549: 2528: 2508:(2): 700–709. 2493: 2481: 2479: 2476: 2473: 2472: 2454: 2442:Universe Today 2428: 2406: 2388: 2373: 2338: 2317: 2302: 2298:Goldstein 2003 2290: 2288:, p. 576. 2278: 2266: 2248: 2236: 2229: 2211: 2190: 2174: 2172:, p. 405. 2162: 2150: 2137: 2136: 2134: 2131: 2128: 2127: 2117: 2103:in January to 2091: 2090: 2088: 2085: 2083: 2080: 2079: 2078: 2073: 2068: 2066:Hindu calendar 2063: 2058: 2053: 2048: 2041: 2038: 2033: 2029: 2025: 2021: 2002: 1999: 1994: 1990: 1986: 1981: 1977: 1973: 1970: 1949: 1945: 1941: 1937: 1924: 1919: 1915: 1911: 1906: 1902: 1898: 1895: 1890: 1886: 1870: 1866: 1859: 1855: 1851: 1847: 1843: 1832: 1828: 1810: 1807: 1804: 1798: 1793: 1789: 1785: 1780: 1776: 1772: 1766: 1762: 1756: 1753: 1750: 1747: 1740: 1736: 1732: 1727: 1724: 1721: 1718: 1711: 1707: 1701: 1697: 1691: 1688: 1685: 1682: 1679: 1676: 1669: 1665: 1661: 1656: 1650: 1647: 1644: 1637: 1633: 1627: 1623: 1617: 1614: 1611: 1608: 1605: 1601: 1596: 1589: 1585: 1581: 1576: 1570: 1567: 1564: 1559: 1555: 1551: 1548: 1545: 1542: 1537: 1533: 1528: 1523: 1517: 1514: 1510: 1505: 1502: 1473: 1470: 1467: 1462: 1458: 1454: 1451: 1448: 1445: 1440: 1436: 1432: 1428: 1425: 1421: 1418: 1414: 1410: 1406: 1402: 1371: 1366: 1362: 1358: 1353: 1349: 1345: 1342: 1339: 1336: 1333: 1328: 1324: 1320: 1317: 1312: 1308: 1304: 1301: 1225: 1224: 1175: 1173: 1166: 1160: 1157: 1142:Universal Time 1119:Ephemeris Time 1110: 1109: 1086: 1082: 1081: 1058: 1054: 1053: 1030: 1026: 1025: 1002: 998: 997: 974: 970: 969: 966: 948:Valid for the 943:secular change 903: 900: 855:ascending node 840:ecliptic plane 808:draconic month 789: 788:Draconic month 786: 782:same direction 722: 721: 672: 670: 663: 647: 644: 636:tropical month 581: 580:Tropical month 578: 574:lunar mansions 551:sidereal month 541:of apparently 530: 529:Sidereal month 527: 437:Gregorian year 359:Synodic period 354: 351: 321: 318: 306:calendar month 216:to full moon. 190:Middle Eastern 181: 178: 128: 127: 42: 40: 33: 26: 24: 18:Sidereal month 14: 13: 10: 9: 6: 4: 3: 2: 2747: 2736: 2733: 2731: 2728: 2726: 2723: 2721: 2720:Units of time 2718: 2717: 2715: 2703: 2698: 2697: 2692: 2685: 2684: 2678: 2674: 2670: 2666: 2665: 2660: 2656: 2655: 2649: 2645: 2641: 2638:. p. 7. 2637: 2633: 2628: 2624: 2618: 2614: 2613: 2607: 2604:. p. 57. 2603: 2599: 2594: 2590: 2586: 2582: 2578: 2574: 2570: 2566: 2562: 2555: 2550: 2546: 2542: 2538: 2534: 2529: 2524: 2519: 2515: 2511: 2507: 2503: 2499: 2494: 2490: 2489: 2483: 2482: 2477: 2468: 2464: 2458: 2455: 2443: 2439: 2438:"Lunar Month" 2432: 2429: 2417: 2410: 2407: 2402: 2398: 2392: 2389: 2385: 2380: 2378: 2374: 2370: 2359: 2355: 2351: 2350: 2342: 2339: 2335: 2331: 2327: 2321: 2318: 2315:, p. 57. 2314: 2309: 2307: 2303: 2300:, p. 65. 2299: 2294: 2291: 2287: 2282: 2279: 2275: 2270: 2267: 2262: 2258: 2252: 2249: 2245: 2240: 2237: 2232: 2226: 2222: 2215: 2212: 2208: 2203: 2201: 2199: 2197: 2195: 2191: 2188:(1st edition) 2187: 2183: 2178: 2175: 2171: 2166: 2163: 2160:, p. 52. 2159: 2158:Angell (1846) 2154: 2151: 2147: 2146:Parker (1950) 2142: 2139: 2132: 2121: 2118: 2096: 2093: 2086: 2081: 2077: 2074: 2072: 2069: 2067: 2064: 2062: 2059: 2057: 2054: 2052: 2049: 2047: 2044: 2043: 2039: 2037: 2019: 2014: 2000: 1997: 1992: 1988: 1984: 1979: 1975: 1971: 1968: 1960: 1958: 1953: 1917: 1913: 1909: 1904: 1900: 1893: 1888: 1884: 1874: 1863: 1840: 1838: 1825: 1822: 1805: 1802: 1791: 1787: 1783: 1778: 1774: 1764: 1760: 1754: 1751: 1745: 1738: 1734: 1730: 1725: 1719: 1716: 1709: 1705: 1699: 1695: 1689: 1686: 1683: 1680: 1674: 1667: 1663: 1659: 1654: 1645: 1642: 1635: 1631: 1625: 1621: 1615: 1612: 1606: 1603: 1599: 1594: 1587: 1583: 1579: 1574: 1565: 1562: 1557: 1553: 1549: 1546: 1540: 1535: 1531: 1526: 1521: 1515: 1512: 1508: 1503: 1500: 1492: 1490: 1485: 1468: 1465: 1460: 1456: 1452: 1449: 1443: 1438: 1434: 1430: 1426: 1423: 1419: 1416: 1408: 1404: 1392: 1389: 1387: 1383: 1364: 1360: 1356: 1351: 1347: 1340: 1334: 1331: 1326: 1322: 1315: 1310: 1306: 1302: 1299: 1291: 1289: 1285: 1280: 1278: 1274: 1270: 1266: 1262: 1258: 1254: 1250: 1246: 1241: 1240: 1236: 1232: 1221: 1218: 1210: 1200: 1196: 1192: 1186: 1185: 1181: 1176:This section 1174: 1170: 1165: 1164: 1158: 1156: 1154: 1149: 1148:("delta-T"). 1147: 1143: 1139: 1135: 1131: 1128: 1124: 1120: 1116: 1108: 1087: 1084: 1083: 1080: 1059: 1056: 1055: 1052: 1031: 1028: 1027: 1024: 1003: 1000: 999: 996: 975: 972: 971: 967: 964: 963: 960: 958: 954: 951: 946: 945:is provided. 944: 940: 935: 933: 929: 925: 921: 917: 913: 909: 902:Cycle lengths 901: 899: 897: 892: 890: 879: 875: 871: 867: 862: 860: 856: 852: 847: 845: 844:orbital nodes 841: 837: 833: 829: 825: 821: 820:nodical month 817: 813: 809: 803: 799: 795: 787: 785: 783: 778: 776: 772: 768: 764: 760: 749: 745: 741: 737: 733: 729: 718: 715: 707: 697: 693: 689: 683: 682: 678: 673:This section 671: 667: 662: 661: 657: 653: 645: 643: 641: 640:tropical year 637: 626: 622: 618: 614: 610: 609:March equinox 606: 601: 599: 595: 591: 587: 586:tropical year 579: 577: 575: 564: 560: 556: 552: 548: 544: 540: 536: 528: 526: 520: 510: 504: 493: 486: 482: 473: 469: 465: 461: 457: 453: 449: 445: 444:Earth's orbit 440: 438: 434: 429: 427: 423: 419: 415: 414:tidal locking 411: 407: 402: 396: 387: 383: 382:synodic month 376: 370: 366: 360: 353:Synodic month 352: 350: 348: 343: 341: 337: 336:synodic month 333: 327: 319: 317: 315: 311: 307: 303: 298: 295: 289: 283: 277: 271: 265: 259: 253: 247: 241: 240: 234: 230: 226: 222: 217: 215: 211: 210:ancient Egypt 207: 203: 199: 195: 191: 187: 179: 174: 170: 165: 161: 159: 155: 151: 147: 143: 136: 124: 121: 113: 102: 99: 95: 92: 88: 85: 81: 78: 74: 71: –  70: 69:"Lunar month" 66: 65:Find sources: 59: 55: 49: 48: 43:This article 41: 37: 32: 31: 19: 2701: 2682: 2663: 2653: 2631: 2611: 2597: 2564: 2560: 2536: 2532: 2505: 2501: 2487: 2457: 2445:. Retrieved 2431: 2419:. Retrieved 2409: 2400: 2391: 2386:, p. 7. 2368: 2361:. Retrieved 2348: 2341: 2336:(1952), 180. 2333: 2329: 2320: 2293: 2281: 2269: 2260: 2251: 2239: 2220: 2214: 2177: 2165: 2153: 2141: 2120: 2115:in December. 2095: 2017: 2015: 1961: 1956: 1955:Then period 1954: 1875: 1864: 1841: 1836: 1826: 1823: 1493: 1488: 1487:The period ( 1486: 1393: 1390: 1385: 1384: 1292: 1287: 1281: 1276: 1272: 1268: 1264: 1260: 1256: 1252: 1244: 1242: 1235:lunar theory 1228: 1213: 1204: 1189:Please help 1177: 1150: 1133: 1114: 1113: 1106: 1078: 1057:anomalistic 1050: 1022: 994: 947: 936: 905: 893: 863: 858: 854: 848: 823: 819: 815: 811: 807: 805: 802:Nodal period 779: 747: 728:Moon's orbit 725: 710: 701: 686:Please help 674: 635: 602: 584:Just as the 583: 550: 535:Moon's orbit 532: 523:JD = 2451545 508: 502: 491: 481:lunar theory 441: 430: 410:lunar phases 405: 381: 379: 344: 331: 329: 299: 229:Lunar cycles 218: 183: 145: 139: 116: 107: 97: 90: 83: 76: 64: 52:Please help 47:verification 44: 2384:Linton 2004 2363:10 February 1261:anomalistic 973:draconitic 832:lunar nodes 822:. The name 816:nodal month 625:fixed stars 543:fixed stars 426:lunar phase 369:Synodic day 332:lunar month 300:In English 202:conjunction 146:lunar month 2714:Categories 2356:. p.  2170:Law (1983) 2111:in May to 2082:References 1284:polynomial 1231:Delaunay's 1159:Derivation 965:Month type 908:its phases 792:See also: 650:See also: 448:elliptical 363:See also: 324:See also: 302:common law 233:Panchangam 180:Variations 158:full moons 80:newspapers 2589:121983695 2313:Lang 2012 2133:Citations 1998:× 1985:− 1959:in days: 1910:× 1894:÷ 1803:× 1784:× 1755:× 1746:− 1717:× 1690:× 1684:− 1675:× 1643:× 1616:× 1595:× 1563:× 1550:× 1466:× 1453:× 1357:× 1332:× 1290:(angle): 1178:does not 1029:sidereal 1001:tropical 928:its orbit 889:precesses 771:full moon 675:does not 590:equinoxes 472:lunations 464:periapsis 418:lunar day 401:synodikós 395:romanized 390:συνοδικός 365:Lunar day 214:full moon 173:libration 154:new moons 2602:Springer 2447:18 April 2040:See also 1516:′ 1427:′ 1269:draconic 1253:tropical 1245:sidereal 1207:May 2024 1085:synodic 857:and the 851:inclined 824:draconic 763:eclipses 704:May 2024 617:ecliptic 494:− 468:apoapsis 452:circular 450:and not 406:lunation 194:European 150:syzygies 110:May 2024 2640:Bibcode 2569:Bibcode 2541:Bibcode 2539:: 342. 2510:Bibcode 2478:Sources 2421:4 April 1279:month. 1277:synodic 1271:month. 1263:month. 1199:removed 1184:sources 1130:seconds 953:J2000.0 836:eclipse 736:perigee 732:apsides 696:removed 681:sources 517:is the 397::  294:vriddhi 223:or the 94:scholar 2735:Months 2619:  2587:  2227:  1089:29.530 1061:27.554 1033:27.321 1005:27.321 977:27.212 882:27.212 870:torque 828:dragon 800:, and 752:27.554 740:apogee 629:27.321 567:27.321 563:sidera 506:where 454:, the 442:Since 208:). In 192:, and 96:  89:  82:  75:  67:  2585:S2CID 2557:(PDF) 2087:Notes 1115:Note: 1071:1.007 950:epoch 767:Saros 765:(see 559:Latin 555:stars 545:(the 521:(and 456:speed 386:Greek 320:Types 288:tithi 282:tithi 270:kṣaya 264:tithi 258:tithi 252:tithi 246:tithi 239:tithi 186:Shona 135:month 101:JSTOR 87:books 2617:ISBN 2467:NASA 2449:2012 2423:2014 2365:2014 2225:ISBN 1944:÷ (A 1876:For 1869:by B 1846:by B 1182:any 1180:cite 1099:2.52 1043:2.17 1015:1.82 987:4.14 920:days 916:full 866:node 738:and 726:The 679:any 677:cite 654:and 513:and 496:3.64 380:The 367:and 276:lopa 243:. A 169:Moon 144:, a 73:news 2673:488 2669:107 2577:doi 2537:190 2518:doi 2506:387 2358:223 2186:866 1952:). 1948:× A 1858:÷ A 1854:= B 1193:by 1132:. 1094:861 1091:588 1066:886 1063:549 1038:554 1035:661 1010:252 1007:582 982:815 979:220 959:): 912:new 884:220 818:or 810:or 754:551 690:by 631:582 596:or 569:661 565:): 483:of 273:or 184:In 156:or 140:In 56:by 2716:: 2671:, 2634:. 2600:. 2583:. 2575:. 2565:34 2563:. 2559:. 2535:. 2516:. 2504:. 2500:. 2465:. 2440:. 2399:. 2376:^ 2367:. 2352:. 2334:62 2332:, 2328:, 2305:^ 2259:. 2193:^ 2013:. 1821:, 1484:. 1382:; 1146:ΔT 1127:SI 1105:× 1103:10 1097:+ 1077:× 1075:10 1069:− 1049:× 1047:10 1041:+ 1021:× 1019:10 1013:+ 993:× 991:10 985:+ 957:TT 934:. 861:. 846:. 806:A 796:, 734:: 642:. 561:: 515:JD 500:10 487:: 439:. 428:. 392:, 388:: 349:. 342:. 297:. 188:, 2675:. 2646:. 2642:: 2625:. 2591:. 2579:: 2571:: 2547:. 2543:: 2526:. 2520:: 2512:: 2469:. 2451:. 2425:. 2403:. 2276:. 2233:. 2034:2 2030:1 2026:2 2022:1 2018:D 2001:T 1993:2 1989:C 1980:1 1976:C 1972:= 1969:P 1957:P 1950:1 1946:1 1942:2 1938:2 1936:C 1923:) 1918:1 1914:A 1905:1 1901:A 1897:( 1889:2 1885:A 1871:2 1867:2 1860:1 1856:1 1852:1 1848:1 1844:1 1837:Q 1833:2 1829:1 1827:A 1809:) 1806:T 1797:) 1792:1 1788:A 1779:1 1775:A 1771:( 1765:2 1761:A 1752:2 1749:( 1739:1 1735:A 1731:1 1726:= 1723:) 1720:T 1710:1 1706:A 1700:2 1696:A 1687:2 1681:1 1678:( 1668:1 1664:A 1660:1 1655:= 1649:) 1646:T 1636:1 1632:A 1626:2 1622:A 1613:2 1610:( 1607:+ 1604:1 1600:1 1588:1 1584:A 1580:1 1575:= 1569:) 1566:T 1558:2 1554:A 1547:2 1544:( 1541:+ 1536:1 1532:A 1527:1 1522:= 1513:A 1509:1 1504:= 1501:Q 1489:Q 1472:) 1469:T 1461:2 1457:A 1450:2 1447:( 1444:+ 1439:1 1435:A 1431:= 1424:A 1420:= 1417:t 1413:d 1409:/ 1405:A 1401:d 1386:T 1370:) 1365:2 1361:T 1352:2 1348:A 1344:( 1341:+ 1338:) 1335:T 1327:1 1323:A 1319:( 1316:+ 1311:0 1307:A 1303:= 1300:A 1288:A 1273:D 1265:F 1257:l 1220:) 1214:( 1209:) 1205:( 1201:. 1187:. 1134:T 1107:T 1101:× 1079:T 1073:× 1051:T 1045:× 1023:T 1017:× 995:T 989:× 910:( 717:) 711:( 706:) 702:( 698:. 684:. 557:( 509:T 503:T 498:× 492:T 384:( 377:. 175:. 137:. 123:) 117:( 112:) 108:( 98:· 91:· 84:· 77:· 50:. 20:)

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