| Penumbral eclipse | |||||||||
_(cropped).jpg) Penumbral eclipse as viewed fromWashington, D.C., 23:53 UTC | |||||||||
| Date | 18 October 2013 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Gamma | 1.1508 | ||||||||
| Magnitude | −0.2706 | ||||||||
| Saros cycle | 117 (52 of 72) | ||||||||
| Penumbral | 239 minutes, 6 seconds | ||||||||
| |||||||||
A penumbrallunar eclipse occurred at the Moon’sdescending node of orbit on Friday, 18 October 2013,[1] with an umbralmagnitude of −0.2706. A lunar eclipse occurs when theMoon moves into theEarth's shadow, causing the Moon to be darkened. A penumbral lunar eclipse occurs when part or all of the Moon's near side passes into the Earth's penumbra. Unlike asolar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on thenight side of Earth. The Moon's apparent diameter was near the average diameter because it occurred 8.2 days afterperigee (on 10 October 2013, at 19:15 UTC) and 6.9 days beforeapogee (on 25 October 2013, at 10:25 UTC).[2]
The eclipse was completely visible overAfrica,Europe, easternSouth America, andwest Asia, seen rising over westernSouth America andNorth America and setting oversouth andeast Asia.[3]
  |
 Visibility map |
.jpg)
Shown below is a table displaying details about this particular lunar eclipse. It describes various parameters pertaining to this eclipse.[4]
| Parameter | Value |
|---|---|
| Penumbral Magnitude | 0.76603 |
| Umbral Magnitude | −0.27064 |
| Gamma | 1.15082 |
| Sun Right Ascension | 13h35m31.9s |
| Sun Declination | -09°57'14.9" |
| Sun Semi-Diameter | 16'03.4" |
| Sun Equatorial Horizontal Parallax | 08.8" |
| Moon Right Ascension | 01h34m19.6s |
| Moon Declination | +11°00'12.1" |
| Moon Semi-Diameter | 15'29.3" |
| Moon Equatorial Horizontal Parallax | 0°56'50.7" |
| ΔT | 67.2 s |
This eclipse is part of aneclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by afortnight.
| October 18 Descending node (full moon) | November 3 Ascending node (new moon) |
|---|---|
|  |
| Penumbral lunar eclipse Lunar Saros 117 | Hybrid solar eclipse Solar Saros 143 |
This eclipse is a member of asemester series. An eclipse in a semester series of lunar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternatingnodes of the Moon's orbit.[5]
The penumbral lunar eclipse onMay 25, 2013 occurs in the previous lunar year eclipse set, and the penumbral lunar eclipse onAugust 18, 2016 occurs in the next lunar year eclipse set.
| Lunar eclipse series sets from 2013 to 2016 | ||||||||
|---|---|---|---|---|---|---|---|---|
| Ascending node | Descending node | |||||||
| Saros | Date Viewing | Type Chart | Gamma | Saros | Date Viewing | Type Chart | Gamma | |
112 | 2013 Apr 25 | Partial | −1.0121 | 117 | 2013 Oct 18 | Penumbral | 1.1508 | |
122 | 2014 Apr 15 | Total | −0.3017 | 127 | 2014 Oct 08 | Total | 0.3827 | |
132 | 2015 Apr 04 | Total | 0.4460 | 137 | 2015 Sep 28 | Total | −0.3296 | |
| 142 | 2016 Mar 23 | Penumbral | 1.1592 | 147.jpg) | 2016 Sep 16 | Penumbral | −1.0549 | |
This eclipse is a part ofSaros series 117, repeating every 18 years, 11 days, and containing 71 events. The series started with a penumbral lunar eclipse on April 3, 1094. It contains partial eclipses from June 29, 1238 through September 23, 1382; total eclipses from October 3, 1400 through June 21, 1815; and a second set of partial eclipses from July 2, 1833 throughSeptember 5, 1941. The series ends at member 71 as a penumbral eclipse on May 15, 2356.
The longest duration of totality was produced by member 35 at 105 minutes, 43 seconds on April 17, 1707. All eclipses in this series occur at the Moon’sdescending node of orbit.[6]
| Greatest | First | |||
|---|---|---|---|---|
| The greatest eclipse of the series occurred on1707 Apr 17, lasting 105 minutes, 43 seconds.[7] | Penumbral | Partial | Total | Central |
| 1094 Apr 03 | 1238 Jun 29 | 1400 Oct 03 | 1563 Jan 09 | |
| Last | ||||
| Central | Total | Partial | Penumbral | |
| 1761 May 18 | 1815 Jun 21 | 1941 Sep 05 | 2356 May 15 | |
Eclipses are tabulated in three columns; every third eclipse in the same column is oneexeligmos apart, so they all cast shadows over approximately the same parts of the Earth.
| Series members 41–62 occur between 1801 and 2200: | |||||
|---|---|---|---|---|---|
| 41 | 42 | 43 | |||
| 1815 Jun 21 | 1833 Jul 02 | 1851 Jul 13 | |||
| 44 | 45 | 46 | |||
| 1869 Jul 23 | 1887 Aug 03 | 1905 Aug 15 | |||
 |  | ||||
| 47 | 48 | 49 | |||
| 1923 Aug 26 | 1941 Sep 05 | 1959 Sep 17 | |||
 |  | |  |  |  |
| 50 | 51 | 52 | |||
| 1977 Sep 27 | 1995 Oct 08 | 2013 Oct 18 | |||
 |  |  |  | | |
| 53 | 54 | 55 | |||
| 2031 Oct 30 | 2049 Nov 09 | 2067 Nov 21 | |||
 |  |  |  |  |  |
| 56 | 57 | 58 | |||
| 2085 Dec 01 | 2103 Dec 13 | 2121 Dec 24 | |||
| 59 | 60 | 61 | |||
| 2140 Jan 04 | 2158 Jan 14 | 2176 Jan 26 | |||
| 62 | |||||
| 2194 Feb 05 | |||||
This eclipse is a part of atritos cycle, repeating at alternating nodes every 135synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.
| Series members between 1817 and 2200 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1817 May 01 (Saros 99) | 1828 Mar 31 (Saros 100) | 1839 Feb 28 (Saros 101) | 1850 Jan 28 (Saros 102) | 1860 Dec 28 (Saros 103) | |||||
| 1893 Sep 25 (Saros 106) | 1915 Jul 26 (Saros 108) | ||||||||
 |  | ||||||||
| 1926 Jun 25 (Saros 109) | 1937 May 25 (Saros 110) | 1948 Apr 23 (Saros 111) | 1959 Mar 24 (Saros 112) | 1970 Feb 21 (Saros 113) | |||||
 |  |  |  |  |  |  |  |  |  |
| 1981 Jan 20 (Saros 114) | 1991 Dec 21 (Saros 115) | 2002 Nov 20 (Saros 116) | 2013 Oct 18 (Saros 117) | 2024 Sep 18 (Saros 118) | |||||
 |  |  |  |  |  | | |  |  |
| 2035 Aug 19 (Saros 119) | 2046 Jul 18 (Saros 120) | 2057 Jun 17 (Saros 121) | 2068 May 17 (Saros 122) | 2079 Apr 16 (Saros 123) | |||||
 |  |  |  |  |  |  |  | ||
| 2090 Mar 15 (Saros 124) | 2101 Feb 14 (Saros 125) | 2112 Jan 14 (Saros 126) | 2122 Dec 13 (Saros 127) | 2133 Nov 12 (Saros 128) | |||||
| 2144 Oct 11 (Saros 129) | 2155 Sep 11 (Saros 130) | 2166 Aug 11 (Saros 131) | 2177 Jul 11 (Saros 132) | 2188 Jun 09 (Saros 133) | |||||
| 2199 May 10 (Saros 134) | |||||||||
This eclipse is a part of the long periodinex cycle, repeating at alternating nodes, every 358synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings.
| Series members between 1801 and 2200 | |||||
|---|---|---|---|---|---|
| 1811 Mar 10 (Saros 110) | 1840 Feb 17 (Saros 111) | 1869 Jan 28 (Saros 112) | |||
| 1898 Jan 08 (Saros 113) | 1926 Dec 19 (Saros 114) | 1955 Nov 29 (Saros 115) | |||
 |  |  |  | ||
| 1984 Nov 08 (Saros 116) | 2013 Oct 18 (Saros 117) | 2042 Sep 29 (Saros 118) | |||
 |  | | |  |  |
| 2071 Sep 09 (Saros 119) | 2100 Aug 19 (Saros 120) | 2129 Jul 31 (Saros 121) | |||
| 2158 Jul 11 (Saros 122) | 2187 Jun 20 (Saros 123) | ||||
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (ahalf saros).[8] This lunar eclipse is related to two partial solar eclipses ofSolar Saros 124.
| October 14, 2004 | October 25, 2022 |
|---|---|
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