Kiddush Levana and the upcoming Lunar Eclipse | R’ Moshe Flohr

While all over the world there was great interest (and even excitement) over the Total Solar Eclipse of August 2017, due to its being a rare phenomenon, a much more common celestial event will be occurring in the next few days. This month we will experience a Total Lunar Eclipse and it is noteworthy even for us non-astronomers as it is something that has Halachic implications.

Why is there an eclipse?

As is well known, the moon reflects the light that it receives from the sun. As the moon revolves around the earth it crosses in between the sun and the earth (which may cause a solar eclipse) and it also goes “behind” the earth. A lunar eclipse occurs when the moon is behind the earth and is in the shadow of earth. Basically the earth is blocking the moon from receiving the rays of the sun.

Halachic Issues

What is important to know regarding an eclipse is that it can only occur when there is a full moon.

An eclipse of the moon is called in the גמרא and Halacha by the term ליקוי הלבנה.

The בית יוסף in סימן תכ”ו brings a תשובת מהרי”ל which says that after the ליקוי הלבנה you can no longer say קידוש לבנה. The meaning of this is as follows:

The lunar month is usually said to be 29 days 12 hours and 44 minutes and 1 חלק. (It should be noted that this amount is only the AVERAGE of each month, but in fact it fluctuates from month to month.) קידוש לבנה may be said each month only when the moon is “ascending” (getting bigger) but not when it is getting smaller. While we assume that this means only during the first half of the month, the exact time that saying קידוש לבנה is allowed is actually a מחלוקת between the מחבר and the רמ”א. The מחבר (סי’ תכ”ו) says until the night of the 16th of the month (meaning that on the 15th of the month you can still say it) and the רמ”א holds until half the month, which according to the “average” month would be 14 days 18 hours and 22 minutes from the molad. (There is a מחלוקת what exactly the מחבר holds, but we will not get into it at this time.)

In the בית יוסף it quotes the תשובת מהרי”ל that since the ליקוי הלבנה occurs at the EXACT midpoint of the month, therefore you cannot say קידוש לבנה afterwards since the ליקוי is proof that it’s the halfway point. This means that even if according to our calculations (i.e. adding 14d 18h 22m to the מולד) it would come out that you can still say קידוש לבנה, however in this case says the בית יוסף you would not.

This month, חודש שבט, there will be a total lunar eclipse on the night of the fifteenth of the month (Sunday night). It will begin at 9:36 PM and end at 2:48 AM. According to the “calculated” zman you should be able to say קידוש לבנה until 10:14 PM. (See at the end for information about this calculation.) However, according to the בית יוסף once there is the ליקוי הלבנה you cannot say it anymore.

It is important to note the following. The total lunar eclipse does not happen all at once. It happens in stages. First a darkening “shadow” falls on the moon. You can still see it but it looks darker. Then parts of the moon start “disappearing” as the strong shadow of the earth starts to cover it. This continues until we reach “total” darkness. Then it goes in reverse. The moon emerges slowly from the shadow until it is shining brightly as before.

Some additional information

Lunar eclipses are classified in three ways. Partial, Penumbral and Total. The earth casts two shadows from the light of the sun. One is a light shadow from the “sides” of the earth. The other is the strong dark shadow from directly behind the earth. When the moon is situated in the “light shadow” it will get slightly darker than usual. This is called a “penumbral eclipse”. (Since it is only slightly darker some people might not even notice any difference from any other night.) A partial eclipse is when only a part of the moon is situated in the strong dark shadow of earth. A total eclipse is when the moon is completely in the full dark shadow of earth.

Eclipses are not that rare. In the 20th century (1901-2000) there were 229. In the current century (2001-2100) there will be 230. However in a 100 year span the amount of TOTAL eclipse occurring is about 35% of all the eclipses that will be (partial, penumbral and total). It should be noted that even when a (total) lunar eclipse is going to happen there are reasons that you may not be see it. First, it could happen during the time that in your location it is daylight. Second, it could be happening at night but not in your geographic area.

The last total lunar eclipse was this past summer during Av (15 Av = July 27, 2018). The previous one was last year ט”ו שבט תשע”ח. The next time a total eclipse happens will be ט”ו סיון תשפ”א (May 26, 2021). The next time a total eclipse happens on ט”ו שבט will be in 18 years, on  January 31, 2037.

Some may wonder, if I can see the לבנה during the time of the penumbral eclipse or when there is a partial eclipse, may I say קידוש לבנה? They want to say the since it is considered only “half” of the month at the EXACT TIME that the total eclipse occurs, therefore until that time (11:41 PM) it should be permitted?

The answer to this should be made by your Rov. However in the שו”ת ישועת משה ח”ג סי’ ל”ז  it states that Kiddush Levana should not be said during ANY PART of the eclipse. That means even if it’s only the beginning (i.e. partial or penumbral) it is not an appropriate time to say it.

The reason, he explains, is we see that it is important to say קידוש לבנה in a “happy” time. For example, not after a Ta’anis and not during the 9 days etc. Also we should say it when we are מבושם, which also means with שמחה. An eclipse the Gemara says is not a good siman for Jews. The משנה ברורה סי’ תק”פ ס”ק ב’ says that we should fast on the day of an eclipse (כשהלבנה לוקה יש להתענות).

Another point to be mentioned is that this הלכה of not saying קידוש לבנה after the time of ליקוי הלבנה is not mentioned at all in שלחן ערוך and is not brought in the משנה ברורה. However the פוסקים all seem to follow the בית יוסף and say not to say קידוש לבנה afterwards.

Which of the following nights will we still be able to say קידוש לבנה

In Lakewood and Monsey:

Friday night the moon will be visible. Ask your Rov if you can make קידוש לבנה on Friday night (there are חילוקי דיעות about this).

מוצאי שבת will be rainy and cloudy, so it will not be able to be said.

Sunday night, between 8 PM and 9:35 PM, it “should” be clear.

In Brooklyn, it looks like there will be clouds/snow for the next three nights.

Final note:

In a number of calendars I have found a major error in the stated time for the last time to say קידוש לבנה. In the עזרת תורה לוח as well as the Satmar Lakewood calendar it gives the time for this month as 5:35 AM. This is incorrect. That is in ארץ ישראל. In the U.S. you need to deduct 7 hours from that time (and minus another 21 minutes, which we cant’ get into). This mistake in calculating סוף זמן קידוש לבנה is in ALL MONTHS LISTED in their calendar. It should be corrected (subtracting 7 hours).

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  1. Have you contacted Ezras Torah about this issue of the 7 hours 21 minutes? I contacted them many many years ago and then again a few years ago. My feeling was that they pretty much understand and agree BUT they said what can we do, Rav Henkin ZTL held like that. But a few years ago I found information in the new sefer printed by Rav Daniel Kleinman, Gevuros Eliyohu, that Rav Henkin held that the 7 hours and 21 minute adjustment SHOULD be made! Last year they actually printed that piece from Rav Henkin themselves in the luach.

  2. I just spoke to Rav Hillel Litwak editor of Luach Ezras Torah, who confirmed that one must minus 7 hours in NYC or 8 hours in Chicago,
    From the Zman printed in the Luach. He did not want to get into the 21 minute kneitch.

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