January 1981 lunar eclipse

A penumbral lunar eclipse took place on Tuesday, January 20, 1981, the first of two lunar eclipses in 1981. In a rare total penumbral eclipse, the entire Moon was partially shaded by the Earth (though none of it was in complete shadow), and the shading across the Moon should have been quite visible at maximum eclipse. The penumbral phase lasted for 4 hours and 24 minutes in all, though for most of it, the eclipse was extremely difficult, if not impossible to see. The moon's apparent diameter was larger because the eclipse occurred 5.2 days after perigee (Perigee on approximately 1981 Jan 15 at 03:01:56.7 UTC).[1]

January 1981 lunar eclipse
Penumbral eclipse
Date20 January 1981
Gamma−1.0141
Magnitude1.0136
Saros cycle114 (57 of 71)
Penumbral263 minutes, 50 seconds
Contacts (UTC)
P105:38:00
Greatest07:49:57
P410:01:50

This was a relatively rare total penumbral lunar eclipse with the moon passing entirely within the penumbral shadow without entering the darker umbral shadow.[2]

More details about the Penumbral Lunar Eclipse of 1981 Jan 20.

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Penumbral Magnitude = 1.01360

Umbral Magnitude = -0.01916

Gamma = -1.01421

Sun Right Ascension = 20.16

Sun Declination = -20.1

Sun Diameter: 1950.4 arc-seconds (32'30.4")

Moon Right Ascension = 8.15

Moon Declination = 19.1

Moon Diameter = 1888.6 arc-seconds (31'28.6")

Earth's Shadow Right Ascension: 8.16

Earth's Shadow Declination: 20.1

Earth's Shadow Diameter: 8,968.32 arc-seconds (2.4912 degrees)

Greatest Eclipse: Tuesday, 20 January 1981 at 07:49:56.7 UTC

Saros Series = 114th (57 of 71)

Visibility

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Eclipses in 1981

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Lunar year series

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Lunar eclipse series sets from 1980–1984
Descending node   Ascending node
Saros Date
Viewing
Type
Chart
Gamma Saros Date
Viewing
Type
Chart
Gamma
109 1980 Jul 27
 
Penumbral
 
1.41391 114 1981 Jan 20
 
Penumbral
 
−1.01421
119 1981 Jul 17
 
Partial
 
0.70454 124 1982 Jan 09
 
Total
 
−0.29158
129 1982 Jul 06
 
Total
 
−0.05792 134 1982 Dec 30
 
Total
 
0.37579
139 1983 Jun 25
 
Partial
 
−0.81520 144 1983 Dec 20
 
Penumbral
 
1.07468
149 1984 Jun 13
 
Penumbral
 
−1.52403
Last set 1980 Aug 26 Last set 1980 Mar 13
Next set 1984 May 15 Next set 1984 Nov 08


Saros series

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Lunar Saros series 114, repeating every 18 years and 11 days, has a total of 71 lunar eclipse events including 13 total lunar eclipses.

First Penumbral Lunar Eclipse: 0971 May 13

First Partial Lunar Eclipse: 1115 Aug 07

First Total Lunar Eclipse: 1458 Feb 28

First Central Lunar Eclipse: 1530 Apr 12

Greatest Eclipse of Lunar Saros 114: 1584 May 24

Last Central Lunar Eclipse: 1638 Jun 26

Last Total Lunar Eclipse: 1674 Jul 17

Last Partial Lunar Eclipse: 1890 Nov 26

Last Penumbral Lunar Eclipse: 2233 Jun 22

Half-Saros cycle

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A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).[3] This lunar eclipse is related to two annular solar eclipses of Solar Saros 121.

January 16, 1972 January 26, 1990
   

See also

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Notes

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  1. ^ Hermit Eclipse: Saros cycle 114
  2. ^ Total Penumbral Lunar Eclipses, Jean Meeus, June 1980
  3. ^ Mathematical Astronomy Morsels, Jean Meeus, p.110, Chapter 18, The half-saros
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