The periodicity and recurrence of lunar (and solar) eclipses is governed by the Saros cycle, a period of approximately 6,585.3 days (18 years 11 days 8 hours). When two eclipses are separated by a period of one Saros, they share a very similar geometry. The two eclipses occur at the same node[1] with the Moon at nearly the same distance from Earth and at the same time of year. Thus, the Saros is useful for organizing eclipses into families or series. Each series typically lasts 12 to 15 centuries and contains 70 or more lunar eclipses.
Lunar eclipses of Saros 166 all occur at the Moon’s ascending node and the Moon moves southward with each eclipse. The series will begin with a penumbral eclipse near the northern edge of the penumbra on 2494 Jul 18. The series will end with a penumbral eclipse near the southern edge of the penumbra on 3738 Aug 13. The total duration of Saros series 166 is 1244.08 years. In summary:
First Eclipse = 2494 Jul 18 19:45:14 TD
Last Eclipse = 3738 Aug 13 07:14:29 TD
Duration of Saros 166 = 1244.08 Years
Saros 166 is composed of 70 lunar eclipses as follows:
| Lunar Eclipses of Saros 166 | |||
| Eclipse Type | Symbol | Number | Percent |
| All Eclipses | - | 70 | 100.0% |
| Penumbral | N | 18 | 25.7% |
| Partial | P | 41 | 58.6% |
| Total | T | 11 | 15.7% |
The 70 lunar eclipses in Saros 166 occur in the order of 10N 19P 11T 22P 8N which corresponds to:
10 Penumbral
19 Partial
11 Total
22 Partial
8 Penumbral
The longest and shortest eclipses of Saros 166 are as follows.
Longest Total Lunar Eclipse: 3107 Jul 27 Duration = 01h46m21s
Shortest Total Lunar Eclipse: 3017 Jun 01 Duration = 00h32m55s
Longest Partial Lunar Eclipse: 3215 Sep 29 Duration = 03h25m56s
Shortest Partial Lunar Eclipse: 2674 Nov 05 Duration = 00h46m46s
Longest Penumbral Lunar Eclipse: 2656 Oct 25 Duration = 04h43m03s
Shortest Penumbral Lunar Eclipse: 2494 Jul 18 Duration = 00h24m36s
The largest and smallest magnitude partial eclipses of Saros 166 are:
Largest Partial Lunar Eclipse: 3215 Sep 29 Magnitude = 0.9781
Smallest Partial Lunar Eclipse: 2674 Nov 05 Magnitude = 0.0373
Local circumstances at greatest eclipse[2] for every lunar eclipse of Saros 166 are presented in the following catalog. For eclipses occurring between the years -1999 to +3000 (2000 BCE to 3000 CE), the sequence number in the first column links to a eclipse geometry diagram and a map from Five Millennium Canon of Lunar Eclipses: -1999 to +3000. A detailed key and additional information about the catalog can be found at: Key to Catalog of Lunar Eclipse Saros Series.
TD of Phase
Seq. Rel. Calendar Greatest Luna Ecl. Pen. Um. ---- Durations ----
Num. Num. Date Eclipse ΔT Num Type QSE Gamma Mag. Mag. Pen. Par. Total
s m m m
01 -34 2494 Jul 18 19:45:14 1432 6116 Nb t- 1.5603 0.0070 -1.0171 24.6 - -
02 -33 2512 Jul 30 02:35:53 1511 6339 N t- 1.4873 0.1429 -0.8850 110.6 - -
03 -32 2530 Aug 10 09:26:46 1592 6562 N t- 1.4146 0.2785 -0.7537 153.2 - -
04 -31 2548 Aug 20 16:20:01 1674 6785 N t- 1.3441 0.4103 -0.6267 184.4 - -
05 -30 2566 Aug 31 23:15:21 1759 7008 N t- 1.2755 0.5387 -0.5034 209.7 - -
06 -29 2584 Sep 11 06:16:14 1846 7231 N t- 1.2116 0.6587 -0.3888 230.1 - -
07 -28 2602 Sep 23 13:21:50 1935 7454 N t- 1.1517 0.7714 -0.2817 247.3 - -
08 -27 2620 Oct 03 20:33:57 2026 7677 N t- 1.0976 0.8736 -0.1853 261.5 - -
09 -26 2638 Oct 15 03:52:17 2119 7900 N t- 1.0489 0.9659 -0.0987 273.4 - -
10 -25 2656 Oct 25 11:18:45 2214 8123 Nx t- 1.0074 1.0448 -0.0254 283.0 - -
11 -24 2674 Nov 05 18:52:17 2312 8346 P t- 0.9718 1.1130 0.0373 291.1 46.8 -
12 -23 2692 Nov 16 02:32:31 2411 8569 P t- 0.9420 1.1702 0.0894 297.6 72.0 -
13 -22 2710 Nov 28 10:19:44 2513 8792 P t- 0.9184 1.2159 0.1304 302.8 86.6 -
14 -21 2728 Dec 08 18:13:34 2616 9015 P t- 0.9008 1.2503 0.1606 306.8 95.9 -
15 -20 2746 Dec 20 02:11:51 2722 9238 P t- 0.8870 1.2774 0.1842 309.9 102.5 -
16 -19 2764 Dec 30 10:14:06 2829 9461 P t- 0.8767 1.2977 0.2015 312.4 107.1 -
17 -18 2783 Jan 10 18:18:02 2939 9684 P t- 0.8680 1.3147 0.2164 314.4 110.9 -
18 -17 2801 Jan 21 02:23:42 3051 9907 P t- 0.8610 1.3284 0.2287 316.1 114.0 -
19 -16 2819 Feb 01 10:26:27 3165 10130 P t- 0.8520 1.3452 0.2448 317.9 117.8 -
20 -15 2837 Feb 11 18:28:15 3280 10353 P t- 0.8424 1.3628 0.2625 319.7 121.8 -
21 -14 2855 Feb 23 02:24:08 3398 10576 P t- 0.8283 1.3882 0.2887 321.9 127.3 -
22 -13 2873 Mar 05 10:15:36 3518 10799 P t- 0.8106 1.4200 0.3219 324.5 133.8 -
23 -12 2891 Mar 16 17:57:55 3641 11022 P t- 0.7856 1.4649 0.3688 328.0 142.3 -
24 -11 2909 Mar 28 01:34:29 3765 11245 P t- 0.7561 1.5179 0.4242 331.8 151.4 -
25 -10 2927 Apr 08 09:00:57 3891 11468 P t- 0.7186 1.5853 0.4944 336.3 161.7 -
26 -09 2945 Apr 18 16:19:09 4019 11691 P t- 0.6742 1.6652 0.5773 341.1 172.5 -
27 -08 2963 Apr 29 23:27:36 4150 11914 P t- 0.6218 1.7598 0.6750 346.4 183.5 -
28 -07 2981 May 10 06:28:37 4282 12137 P t- 0.5630 1.8660 0.7845 351.6 194.1 -
29 -06 2999 May 21 13:21:13 4417 12360 P t- 0.4971 1.9853 0.9069 356.7 204.2 -
30 -05 3017 Jun 01 20:06:36 4554 12583 T t- 0.4253 2.1156 1.0403 361.4 213.2 32.9
31 -04 3035 Jun 13 02:46:10 4692 12806 T t- 0.3480 2.2559 1.1834 365.5 220.9 67.0
32 -03 3053 Jun 23 09:21:35 4833 13029 T+ pp 0.2669 2.4035 1.3336 368.7 227.1 85.6
33 -02 3071 Jul 04 15:52:57 4976 13252 T+ pp 0.1819 2.5583 1.4906 370.9 231.6 97.4
34 -01 3089 Jul 14 22:23:10 5121 13475 T+ pp 0.0956 2.7157 1.6500 372.1 234.3 104.0
35 00 3107 Jul 27 04:52:55 5268 13698 T+ pp 0.0082 2.8752 1.8111 372.1 235.1 106.4
36 01 3125 Aug 06 11:25:09 5417 13921 T- pp -0.0776 2.7473 1.6843 370.9 234.1 104.7
37 02 3143 Aug 17 17:58:18 5568 14144 T- pp -0.1633 2.5897 1.5275 368.7 231.2 98.9
38 03 3161 Aug 28 00:37:03 5721 14367 T- pp -0.2448 2.4399 1.3782 365.5 226.8 89.0
39 04 3179 Sep 08 07:20:17 5877 14590 T pp -0.3231 2.2961 1.2345 361.4 220.9 73.8
40 05 3197 Sep 18 14:11:39 6034 14813 T -t -0.3952 2.1639 1.1022 356.7 213.9 50.8
TD of Phase
Seq. Rel. Calendar Greatest Luna Ecl. Pen. Um. ---- Durations ----
Num. Num. Date Eclipse ΔT Num Type QSE Gamma Mag. Mag. Pen. Par. Total
s m m m
41 06 3215 Sep 29 21:09:13 6193 15036 P -t -0.4627 2.0402 0.9781 351.5 205.9 -
42 07 3233 Oct 10 04:17:12 6355 15259 P -t -0.5223 1.9312 0.8686 346.2 197.5 -
43 08 3251 Oct 21 11:33:30 6518 15482 P -t -0.5756 1.8338 0.7705 340.8 188.9 -
44 09 3269 Oct 31 18:59:43 6684 15705 P -t -0.6211 1.7504 0.6866 335.7 180.4 -
45 10 3287 Nov 12 02:35:10 6852 15928 P -t -0.6598 1.6797 0.6153 331.0 172.4 -
46 11 3305 Nov 23 10:20:42 7022 16151 P -t -0.6906 1.6233 0.5586 326.8 165.4 -
47 12 3323 Dec 04 18:15:16 7193 16374 P -t -0.7150 1.5786 0.5138 323.2 159.4 -
48 13 3341 Dec 15 02:16:52 7367 16597 P -t -0.7343 1.5430 0.4787 320.0 154.3 -
49 14 3359 Dec 26 10:26:35 7543 16820 P -t -0.7476 1.5182 0.4547 317.5 150.5 -
50 15 3378 Jan 05 18:41:42 7722 17043 P -t -0.7567 1.5009 0.4387 315.4 147.8 -
51 16 3396 Jan 17 03:01:26 7902 17266 P -t -0.7630 1.4883 0.4280 313.5 145.9 -
52 17 3414 Jan 28 11:22:34 8084 17489 P -h -0.7686 1.4767 0.4190 311.7 144.2 -
53 18 3432 Feb 08 19:45:35 8268 17712 P -h -0.7735 1.4662 0.4117 309.8 142.7 -
54 19 3450 Feb 19 04:07:27 8455 17935 P -h -0.7797 1.4529 0.4022 307.7 140.8 -
55 20 3468 Mar 01 12:26:56 8643 18158 P -h -0.7883 1.4349 0.3886 305.3 138.3 -
56 21 3486 Mar 12 20:42:44 8834 18381 P -h -0.8005 1.4100 0.3685 302.2 134.8 -
57 22 3504 Mar 24 04:54:09 9026 18604 P -h -0.8170 1.3771 0.3410 298.6 129.8 -
58 23 3522 Apr 04 12:59:23 9221 18827 P -h -0.8391 1.3336 0.3033 294.0 122.8 -
59 24 3540 Apr 14 20:58:16 9418 19050 P -h -0.8670 1.2794 0.2549 288.4 113.0 -
60 25 3558 Apr 26 04:50:46 9616 19273 P -h -0.9009 1.2141 0.1958 281.7 99.6 -
61 26 3576 May 06 12:37:21 9817 19496 P -h -0.9403 1.1388 0.1265 273.9 80.6 -
62 27 3594 May 17 20:16:12 10020 19719 P -h -0.9868 1.0504 0.0442 264.4 48.0 -
63 28 3612 May 28 03:50:28 10225 19942 N -h -1.0379 0.9538 -0.0467 253.4 - -
64 29 3630 Jun 08 11:18:28 10432 20165 N -h -1.0949 0.8463 -0.1485 240.3 - -
65 30 3648 Jun 18 18:43:27 10641 20388 N -h -1.1549 0.7336 -0.2561 225.3 - -
66 31 3666 Jun 30 02:02:56 10853 20611 N -h -1.2200 0.6117 -0.3731 207.4 - -
67 32 3684 Jul 10 09:22:13 11066 20834 N -h -1.2860 0.4885 -0.4921 186.8 - -
68 33 3702 Jul 22 16:38:57 11281 21057 N -a -1.3547 0.3603 -0.6164 161.8 - -
69 34 3720 Aug 01 23:56:41 11499 21280 N -a -1.4231 0.2333 -0.7402 131.2 - -
70 35 3738 Aug 13 07:14:29 11718 21503 N -a -1.4917 0.1060 -0.8648 89.2 - -
[1] The Moon's orbit is inclined about 5 degrees to Earth's orbit around the Sun. The points where the lunar orbit intersects the plane of Earth's orbit are known as the nodes. The Moon moves from south to north of Earth's orbit at the ascending node, and from north to south at the descending node.
[2]Greatest eclipse is defined as the instant when Moon passes closest to the axis of Earth's shadow.
The Gregorian calendar is used for all dates from 1582 Oct 15 onwards. Before that date, the Julian calendar is used. For more information on this topic, see Calendar Dates. The Julian calendar does not include the year 0. Thus the year 1 BCE is followed by the year 1 CE (See: BCE/CE Dating Conventions ). This is awkward for arithmetic calculations. Years in this catalog are numbered astronomically and include the year 0. Historians should note there is a difference of one year between astronomical dates and BCE dates. Thus, the astronomical year 0 corresponds to 1 BCE, and astronomical year -1 corresponds to 2 BCE, etc..
The coordinates of the Sun used in these predictions are based on the VSOP87 theory [Bretagnon and Francou, 1988]. The Moon's coordinates are based on the ELP-2000/82 theory [Chapront-Touze and Chapront, 1983]. For more information, see: Solar and Lunar Ephemerides. The revised value used for the Moon's secular acceleration is n-dot = -25.858 arc-sec/cy*cy, as deduced from the Apollo lunar laser ranging experiment (Chapront, Chapront-Touze, and Francou, 2002).
The largest uncertainty in the eclipse predictions is caused by fluctuations in Earth's rotation due primarily to tidal friction of the Moon. The resultant drift in apparent clock time is expressed as ΔT and is determined as follows:
A series of polynomial expressions have been derived to simplify the evaluation of ΔT for any time from -1999 to +3000. The uncertainty in ΔT over this period can be estimated from scatter in the measurements.
The Besselian elements used in the predictions were kindly provided by Jean Meeus. All eclipse calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Some of the information presented on this web site is based on data originally published in Five Millennium Canon of Lunar Eclipses: -1999 to +3000 and Five Millennium Catalog of Lunar Eclipses: -1999 to +3000.
Permission is freely granted to reproduce this data when accompanied by an acknowledgment:
"Eclipse Predictions by Fred Espenak and Jean Meeus (NASA's GSFC)"
