A weekly feature of Torah Tidbits to help clarify practical and conceptual aspects of the Jewish Calendar, thereby better fulfilling the mitzva of HaChodesh HaZeh Lachem...
Based on some reader feedback and comments, we will write a little more on the situation presented in last week's issue - namely, the last opportunity for Kiddush L'vana when there is a lunar eclipse that occurs before the official "end of K.L. time".
As previously stated, the deadline for K.L. is the NIGUD, a.k.a. opposition, a.k.a. full moon. However, it is the calculated NIGUD, based on the average time it takes the moon to go through its cycle of phases, and NOT the astronomical instant of opposition, that can differ from the calculated time by a few minutes to many hours - before or after the calculated time.
This results in one of two situations each month:
(2) Or, it can be that we are permitted to say K.L. even after the moon is full and is actually waning, i.e. decreasing in size (brightness). Again, that is so because we follow the average figures and not the actual (astronomical) times.
The fact is, the human eye will see the moon as full for quite a number of hours before and after the actual NIGUD, so neither situation (1) or (2) is a problem. In other words, keeping to the halachically accepted timing, although it does not perfectly fit with the actual timing, does not cause us to sense any contradiction to the reality. Whether this is part of the halachic reasoning in setting the limits for K.L. or not, is another issue.
The question about a lunar eclipse affecting the ability to say K.L. or not is the subject of differing halachic opinions. In last week's TT, we did NOT present all sides of the issue - just the one that I (Phil) personally found most intriguing.
Here then, is a fuller presentation, but still probably not the whole picture. Just a bit more information on the subject.
Most of the treatment of this topic in Torah Tidbits has come from Sefer Kiddush L'vana - Otzar Halachot U'Minhagim (Book on K.L. - treasury of laws and customs) by R' Yaakov Tannenbaum, Jerusalem.
He cites the Maharil and others in being of the opinion that once the eclipse occurs (actually, once it noticeably begins), one can no longer say K.L. even though there remains more time until the calculated deadline.
This is countered by the opinion of the Pri Megadim who says that we follow the calculation based on average (as presented earlier) and that this is the whole story. It does not matter that the astronomical facts clash with the halachic timing, or even that the experience of the eclipse clashes. Neither is relevant, because the halacha uses the average calculations.
Then comes the opinion mentioned last week - which is actually a few opinions with slight variations - that whereas knowledge of the "real" full moon will not affect the deadline of K.L., the personal experience of the lunar eclipse combined with the knowledge of its significance do not "allow" the person to say K.L. after the eclipse (and before the official deadline).
There is a distinction drawn by some who comment on the topic between locations on Earth where the eclipse will not be seen as opposed to an individual not seeing it where others see it.
The author concludes that preferably one should say K.L. on a Friday night (something usually not done) before an eclipse, rather than on Motza'ei Shabbat (the preferred time for K.L.) after an eclipse has occurred (but before the calculated deadline, of course).
Another opinion that might factor into this discussion is the one who says that the deadline for K.L. does not depend on the NIGUD (average or actual) but rather on 15 full days after the molad.
It would seem that this opinion would allow saying K.L. after an eclipse, since the NIGUD is not the determining factor.
Others argue that in other months, the 15 days after the molad is acceptable because the moon still looks full and nothing happened to show us otherwise. A lunar eclipse, however, demonstrates that full moon already took place, even though a look at the moon would not show it.