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Luach Sof Zman Kiddush Levana-5779

Jerusalem times 

	Molad Solar time	Lechatchila-Zman Rama 14 days, 18 hrs, 22 min	Zman Michaber 15 days	Zman Chasam Sofer 15 days 12 hrs 22 min
Adar 1	Monday 30th Shevat  11:36 p.m.	Tuesday 14th Adar 1 5:58 p.m.	Tuesday night 14th Adar 1 11:36 p.m.	Wednesday morning 15th Adar 1 11:58 p.m.
Adar 2	Wednesday afternoon, 29th of Adar I,  12:20 pm	Thursday morning, 14th Adar 2 6:42 am	Thursday afternoon, 14th Adar 2 12:20 pm	Thursday night, 15th Adar 2 12:44 am

*Jerusalem times: All times in the first chart below are for Jerusalem

**For your time zone: Add or subtract hours for your time zone from each of the three opinion to calculate when the time for you arrives.

Example New York time zone

	Molad	Lechatchila-Zman Rama 14 days, 18 hrs, 22 min	Zman Michaber 15 days	Zman Chasam Sofer 15 days 12 hrs 22 min
Adar 1	Monday 29th Shevat  4:36 p.m.	Tuesday morning 14th Adar 1 10:58 a.m.	Tuesday afternoon 14th Adar 1 4:36 p.m.	Wednesday morning 15th Adar 1 4:58 a.m.
Adar 2	Wednesday afternoon, 29th of Adar I,  5:20 am	Wednesday night, 14th Adar 2 11:42 pm	Thursday morning, 14th Adar 2 5:20 am	Thursday afternoon, 15th Adar 2 5:44 pm

5. Sof Zman Kiddush Levana-Until what day of the month may Kiddush Levana be said?[1]

The opinions: Kiddush Levana may only be recited within the first half of the month. A lunar month consists of 29 days, 12 hours and 793 Chalakim.[2] Thus, it may only be said up to 14 days 18 hours and 396.5 chalakim [i.e. 22 minutes] past the Molad.[3] [This time is known as Zman Rama. However, there are opinions[4] who allow it to be said until 15 complete days past the Molad. This time is known as Zman Michaber. Other opinions[5] allow in a time of need to say Kiddush Levana with a blessing up until the night of the 16th of the month, including the night of the 16th. Others[6] rule it may even initially be said in a time of need up until 15 days 12 hours and 22 minutes from the Molad, which is 18 hours past the time of the first opinion.[7] This time is known as Zman Chasam Sofer. Others[8] suggest it may be said even past this time [up until the end of the month].[9] Others[10] allow saying it past the above times [up until the end of the month] if one says it from the Tur or Gemara.[11]

The final practice: Practically, initially one is to be very careful to recite Kiddush Levana prior to the end time of the first/earliest opinion [i.e. Zman Rama]. This applies to both Ashkenazim and Sephardim.[12] However, in the event that one already missed the time of the first/earliest opinion, then many Ashkenazim rely on the second opinion above, to recite it until 15 full days past the Molad [i.e. Zman Michaber].[13] Likewise, some Sephardim rely on this opinion, although many recite it without Hashem’s name once it is past the Zeman Rama.[14] Amongst Chabad Chassidim, many rely on the third opinion to recite it up until 15 days, 12 hrs and 22 minutes from the Molad [i.e. Zeman Chasam Sofer].[15] Practically, one is to contact a Rav for direction as whether he may rely on one of the later approaches and whether he may rely to read the blessing from the Tur or Gemara.[16]]

Summary: One is to beware to recite Kiddush Levana prior to 14 days 18 hours and 396.5 chalakim past the Molad. If it is past the first half of the month, one is to contact a Rav.   Example of opinions: Molad of Adar was on Monday evening, the 30th of Shevat, at 12:00 AM [Jerusalem time]: *This is a theoretical example-for the actual accurate calculation see the next step! 1.       First opinion-Zman Rama [14 days and 18:22 hours]: Kiddush Levana may be said until Tuesday evening, the 15th of Adar 1, until 6:22 p.m [in Jerusalem]. [In the Diaspora, it can only be said until this time arrives in Jerusalem.] 2.       Second opinion-Zman Michaber [15 days]: Kiddush Levana may be said until Tuesday evening, the 15th of Adar 1, until 12:00 a.m [in Jerusalem]. [In the Diaspora, it can be said until this time arrives in Jerusalem.] 3.       Third opinion-Zman Chasam Sofer [15 days 12 hrs 22 min]: Kiddush Levana may be said until Wednesday 12:22 p.m, the 15th of Adar 1, until 12:00 p.m [in Jerusalem]. [In the Diaspora, it can be said until this time arrives in Jerusalem.]   How to practically calculate the end time for Kiddush Levana: 1.       Step 1-Molad time: Look up the exact time that the Molad occurred in Jerusalem [See https://www.torahcalc.com/molad/ to look up what time the Molad of the current month took place in Jerusalem]. 2.       Step 2-Detract solar versus watch time difference:[17] Detract 21 minutes from that time to supplement for the difference between the current watch time in Jerusalem versus the real solar time [Jerusalem is 21 minutes later than its real solar time.] a.       To note that there are three other approaches regarding the amount of time one must calculate as the difference between the solar and watch time. See Luach Itim Lebina for all four opinions. Above we have chosen the most commonly accepted approach. 3.       Step 3-Calculate to your local time zone: Calculate the exact time it was in your time zone when the Molad occurred in the above calculated time in Jerusalem. 4.       Step 4-Add end time of Kiddush Levana: Add the end time of Kiddush Levana in accordance to whatever opinion you follow [i.e. Zeman Rama; Zeman Michaber; Zeman Chasam Sofer].   Example for one in New York: 1.       Molad in Jerusalem occurred at 11:57 p.m on a Monday night, the 30th of Shevat 2.       Minus 21 minutes = 11:36 p.m. 3.       Seven hours back for New York time zone = 4:36 p.m, Monday afternoon, 29th of Shevat. 4.       Add opinion of end time for Kiddush Levana, calculating it from 4:36 p.m. Thus, for example, according to the Zeman Rama, add 14 days 18 hrs and 22 min, to the above time achieved in step 3. This would calculate the end time of Kiddush Levana in Jerusalem to be on Tuesday the 14th Adar 5:58 p.m. and in New York on Tuesday the 14th of Adar 10:58 a.m. According to the Zeman Michaber, it would be Tuesday the 14th Adar [night of 15th] 11:36 p.m. and in New York on Tuesday the 14th of Adar 4:36 p.m. According to the Zeman Chasam Sofer, it would be Wednesday the 15th Adar 11:58 p.m. and in New York on Wednesday the 15th of Adar 4:58 a.m.

Luach Sof Zman Kiddush Levana-5779

 

Jerusalem times

 5779

	Molad Solar time	Lechatchila-Zman Rama 14 days, 18 hrs, 22 min	Zman Michaber 15 days	Zman Chasam Sofer 15 days 12 hrs 22 min
Adar 1	Monday 30th Shevat  11:36 p.m.	Tuesday 14th Adar 1 5:58 p.m.	Tuesday night 14th Adar 1 11:36 p.m.	Wednesday morning 15th Adar 1 11:58 p.m.
Adar 2	Wednesday afternoon, 29th of Adar I,  12:20 pm	Thursday morning, 14th Adar 2 7:22 am	Thursday afternoon, 14th Adar 2 12:20 pm	Thursday night, 15th Adar 2 3:44 am
Nissan
Sivan
Tamuz
Av
Elul

*Jerusalem times: All times in the first chart below are for Jerusalem

**For your time zone: Add or subtract hours for your time zone from each of the three opinion to calculate when the time for you arrives.

 

Example New York time zone

	Molad	Lechatchila-Zman Rama 14 days, 18 hrs, 22 min	Zman Michaber 15 days	Zman Chasam Sofer 15 days 12 hrs 22 min
Adar 1	Monday 29th Shevat  4:36 p.m.	Tuesday morning 14th Adar 1 10:58 a.m.	Tuesday afternoon 14th Adar 1 4:36 p.m.	Wednesday morning 15th Adar 1 4:58 a.m.
Adar 2
Nissan
Sivan
Tamuz
Av
Elul

Summary: One is to beware to recite Kiddush Levana prior to 14 days 18 hours and 396.5 chalakim past the Molad. If it is past the first half of the month, one is to contact a Rav. Maaseh Shehaya Story of Rebbe Rashab from memoirs of Rav Yaakov Landau[18]-Free Translation Date: Motzei Shabbos Beshalach 18th Shvat[19], A number of members of Anash, myself included[20], had not recited Kiddush Levana, and on Friday night the moon became visible. I entered into the Rebbe Rashab during the Shabbos Friday night meal, after the Chazara on the Mamar “Az Yashir”, in order to ask his opinion whether to say Kiddush Levana or not. The Rebbe Rashab replied to me: There is a lengthy discussion on this matter. Reb Dovid Openhaimer has a lengthy response on this, and he concludes that one is to say Kiddush Levana [on Shabbos]. However the Shvus Yaakov rules one is not to say Kiddush Levana. Reb Dovid Openhaimer discusses these points and he says that there are no Techumin [above ten Tefachim] and that all the prayers are elevated. The Shvus Yaakov however negates this. Reb Yaakov Landau then asked: The above discussion [mentioned in the Shvus Yaakov and Rav Dovid Openhaimer] is only with regards to saying Kiddush Levana on Shabbos, however today [on the 17th of Shvat] it is also after the time. The Rebbe Rashab replied: Tonight is already passed the time of Kiddush Levana. (The Rebbe then began calculating the amount of time that had passed since the Molad and the last time for Kiddush Levana had been on Thursday night.) The Rebbe then concluded “if so then it is better to say it tomorrow than to say it tonight.” It once occurred by my father [The Rebbe Maharash] that they recited Kiddush Levana 17 days after the Molad. However on Shabbos I never saw him say Kiddush Levana. This occurred in Lubavitch. After my father [the Rebbe Maharash] passed away it once occurred that the congregation recited Kiddush Levana on the second night of Sukkos. I said Kiddush Levana earlier. I saw the moon earlier so I already said the Bracha, however the rest of the congregation said it on the second night of Sukkos. (The Rebbe then mentioned to me a certain Rabbi that ruled they should say Kiddush Levana then.) Midmuvsky then reminded me that Reb Yisrael Noach once said Kiddush Levana on the second night of Pesach. Based on this one can also say Kiddush Levana on Shabbos as it is the same reason. Nevertheless I never witnessed anyone saying Kiddush Levana on Shabbos and in truth it is a bit difficult to accept such a practice. In my father’s time there were those that said Kiddush Levana after 17 days passed from the Molad. They awoke before daybreak and said Kiddush Levana. My father was always accustomed to awaken before daybreak however us they had to especially awaken for this occasion. That entire night someone stood guard outside to see if the moon would be seen. Feivish was standing guard. Practically, it is better [for Rav Landau] to say Kiddush Levana tomorrow night than to say it tonight. Tomorrow is the 17th day past the Molad. The Molad was at 12:00, thus you can say it tomorrow. Regarding saying Kiddush Levana on the 16th such an opinion is recorded in the Heishiv Moshe, however this was seemingly the occurrence with my father [the Rebbe Maharash]. The Rebbetzin Shterna Sara stated: I remember that at that night they all went outside with Sefarim. The Rebbe Rashab replied: This occurred very late at night. Rav Yaakov Landau asked: So it was said without the loophole of using a Gemara or Rif. The Rebbe Rashab replied: Without using any loopholes. To do loopholes you don’t need to wait for the date to be the 17th, you can do it anytime.   Story of the Tzemach Tzedek and Reb Hillel Paritcher[21] During a certain snowy winter month Reb Hillel visited the city of Lubavitch, the town of residence of the Tzemach Tzedek. The moon had yet to be seen during that month and the last possible day to say Kiddush Levana had arrived. Reb Hillel sent a Pan to the Tzemach Tzedek to receive a blessing that the moon should be seen that night. The Tzemach Tzedek guaranteed Reb Hillel that the moon would indeed appear. Reb Hillel proceeded to station people outside as guard to announce to him when the moon becomes visible. In the midst of the night word came to Reb Hillel that the moon has appeared. Upon going outside, he saw that the moon was a bit blurry covered by light clouds. He said that the Tzemach Tzedek said the moon would be seen, and therefore it has to be seen in a clear fashion, so he returned back inside waiting for a clearer appearance. Slightly prior to daybreak the moon appeared clearly without any clouds interfering. Reb Hillel immediately went outside and recited Kiddush Levana. He then remarked that it once happened in his younger age that an entire month passed without a visible moon, although back then he was strong enough to handle such an occurrence. However, now in his old age he does not know how he would have been able to react if the moon had not been seen.

Q&A What has precedence, Davening Maariv or reciting Kiddush Levana?[22] One is to Daven Maariv prior to reciting Kiddush Levana, as Maariv is a more common Mitzvah and hence receives precedence. If however there is suspicion that one will not be able to say Kiddush Levana afterwards that month due to cloudy skies, then one is to say Kiddush Levana prior to Maariv.   What comes first, Havdala in Shul [for those Shuls which say Havdala] or Kiddush Levana? There are different customs which exist in this matter.[23] The Chabad custom is to first recite Havdala and then to recite Kiddush Levana.[24] May one recite Kiddush Levana prior to Megillah reading on Purim night?[25] If a congregation has not yet recited Kiddush Levana, they are to do so prior to Megillah reading.[26]   If the moon became visible during Maariv may one stop in middle to say Kiddush Levana?[27] If one will certainly be unable to say Kiddush Levana after Maariv, such as that by then the time for Kiddush Levana will have expired, then he may stop in middle of Shema or Birchas Shema and recite Kiddush Levana. [In such a case he may only recite the actual blessing and not any of the other verses prior to or post the blessing.[28]] If the moon became visible during the reading of the Megillah on Purim may one stop in middle to say Kiddush Levana?[29] If the congregation did not yet recite Kiddush Levana and will certainly be unable to say Kiddush Levana after the reading, such as that by then the time for Kiddush Levana will have expired, then the congregation may stop in middle of the Megillah reading and recite Kiddush Levana. However, if the congregation already recited Kiddush Levana and there is an individual that did not yet recite it then since they will continue the reading while he goes outside to recite it, therefore he is to remain with the congregation for the reading of Megillah even if this will cause him to miss Kiddush Levana.   May one say Kiddush Levana if there is a Lunar Eclipse?[30] A lunar eclipse can only occur when the moon is full. This is a clear sign that the first half of the month has passed. In such a case one may no longer say Kiddush Levana even if in accordance to our calculation there is time still remaining.

_______________________________________________________________

[1] See Sanhedrin 41b; Michaber/Rama 426:3; Yabia Omer 8:42 for a thorough analysis of all opinions

Background and other opinions:

The Talmudic ruling “until the 16^th day” The Gemara in Sanhedrin 41b state that “Rebbe Yochanon says the month may be sanctified until the moons lacking is complete.” The Gemara offers two opinions as to when this time is reached. Rav Yehuda says it is reached by the 7^th and Nehardaiy says it is reached by the 16^th [i.e. full moon]. The Rishonim rule like the latter opinion of Nehardaiy. [Haeshkol Rosh Chodesh 2:4; Sefer Hameoaros Brachos; Tur 426]

Interpreting and calculating “until the 16^th day”: The intent of “until the 16^th” is up until the start of the 16^th day, but not including the 16^th day [i.e. a full 15 days]. [Tur ibid; Sefer Hameoros ibid; Rambam 10:17 as learns Rabbeinu Manoach and Kesef Mishneh ibid; Michaber 426:3; Peri Chadash 426] Furthermore, these days are measured from the Molad, and not from the start of the month. [Tur ibid; Michaber ibid] Likewise, these days are calculated as 24-hour days and not by weekdays. [M”A 426:12; M”B 426:17] Furthermore, some Poskim rule that it is measured as half of the true days of the lunar orbit, which is half of 29 days, 12 hrs and 793 Chalakim which equals 14 days 18 hours and 396.5 chalakim past the Molad. [Beis Yosef 426 in name of Tehsuvah Ashkenazis; Maharil 19; 155; Maryu 159; Mateh Moshe 533; Rama 426:3; Bach 426; Shlah; Chayeh Adam 118:14; Noheg Katzon Yosef p. 144; Nishal David 3:10; Noda Beyehuda Kama O.C. 41; Sefer Yehoshua 14; Rav Poalim 2:38; Taharas Hamayim Beis 29; Kitzur SHU”A 97:10; Kaf Hachaim 426:53] Other Poskim, however, argue that it is literally 15 days. [Beis Yosef 426; Michaber 426:3; Halacha Berurah 426:7; Shvus Yaakov 3:31; Siddur Yaavetz; Yeshuos Yaakov 426; Rosh Mashbir 14; Biur Halacha 426:3; Atzei Berushim 63; Yagel Yaakov 60; Shnos Chaim 14:21] Furthermore, some Poskim argue and rule that it is slightly half way into the 16^th day, which is 15 days, 12 hours, and 22 minutes. [Chasam Sofer 102] Furthermore, some Poskim argue and rule that the 16^th day mentioned in the Gemara includes the entire 16^th, and thus one may say Kiddush Levana until the night of the 16^th, including that entire night. [Kneses Hagedola 426 in name of Rabbeinu Peretz; Meiri; Elya Raba 426:8; Heishiv Moshe 14; Tzeror Chesed; Shoel Umeishiv Kama 3:151; Yagel Yaakov 60; Beis Yisrael 80 that so did Apter Rav, and Yismach Moshe] Furthermore, some learn that all the above times are calculated from the start of the month and not from the Molad and hence one may say it always until the night of the 16^th of that month, throughout that entire night. [See Beis Yisrael 80]

Summary ruling of Michaber and Sefaradi custom: The Michaber ibid rules that Kiddush Levana may be said up to 15 full days past the Molad. Once the 16^th day past the Molad has begun it may no longer be said. [Michaber 426:3; Beis Yosef 426] Thus according to the Michaber one has 6 more hours past the time of the Rama to say Kiddush Levana. Regarding the Sefaradi ruling: Many Sephardi Poskim rule that one is to follow the opinion of the Rama in these matters, as Safek Brachos Lehakeil, even against the Michaber. [Rav Poalim 2:38; Kaf Hachaim 426:53; Rav Yaakov Yosef] However some rule that Sephardim may be lenient like the Michaber, although not like any of the other opinions. [Yabia Omer 8:42]

Summary ruling of Rama and Ashkenazi custom: The Rama rules it may be said until 14 days 18 hours and 396.5 chalakim past the Molad. [Rama 426:3] Some Ashkenazi Poskim conclude like this opinion [Chayeh Adam 118:14; Kitzur SHU”A 97:10; Poskim ibid] However, others rule one may be lenient like the Michaber [Biur Halacha “Velo Tes Zayin Bechlal”; Poskim ibid] or even like the Chasam Sofer and latest approach. [see Poskim ibid]

Chabad custom: The Rebbe in 1961 15^th Sivan said Kiddush Levana 1.5 hours past the time. The Rebbe stated he relies on the Chasam Sofer ibid; Rabbi Mordechai Perlow states that he remembers that a number of times they said Kiddush Levana in Lubavitch on the night of the 16^th from a Gemara Sanhedrin; The Rebbe Rashab once said Kiddush Levana 17 days past the molad [Memoirs of Rav Yaakov Landau, brought in Shemuos Vesipurim p. 184 see below] Rav Avraham Chaim Naa’h in Shnos Chaim 14:21 rules it may be said until 15 full days from the Molad

^[2] There are 1080 Chalakim in an hour. [Tur 427]

[3] Rama 426:3; Beis Yosef 426 in name of Tehsuvah Ashkenazis; Maharil 19; 155; Maryu 159; Mateh Moshe 533; Rama 426:3; Bach 426; Shlah; Chayeh Adam 118:14; Noheg Katzon Yosef p. 144; Nishal David 3:10; Noda Beyehuda Kama O.C. 41; Sefer Yehoshua 14; Rav Poalim 2:38; Taharas Hamayim Beis 29; Kitzur SHU”A 97:10; Kaf Hachaim 426:53

Calculating from Molad: The month begins at the time of the Molad of that month. Hence, one can say Kiddush Levana until the above time passes from the Molad and he is not to calculate it from Rosh Chodesh. [See Michaber and Rama ibid and Poskim in background]

Other Opinions: Some write one counts the above time not from the Molad but from Rosh Chodesh. [Taamei Haminhagim p. 200; See M”A 426:12; Beis Yisrael 80]

[4] Michaber 426:3; Beis Yosef 426; Halacha Berurah 426:7; Shvus Yaakov 3:31; Siddur Yaavetz; Yeshuos Yaakov 426; Rosh Mashbir 14; Biur Halacha 426:3 “Velo Tes Zayin Bechlal”; Atzei Berushim 63; Yagel Yaakov 60; Shnos Chaim [Rav Avraham Chaim Naah] 14:21

[5] Kneses Hagedola 426 in name of Rabbeinu Peretz; Meiri; Elya Raba 426:8; Heishiv Moshe 14; Tzeror Chesed; Shoel Umeishiv Kama 3:151; Yagel Yaakov 60; Beis Yisrael 80 that so did Apter Rav, and Yismach Moshe [These opinions are recorded in: Shvus Yaakov 3:31; Chasam Sofer 102; Alef Lamagen 581:22; Biur Halacha 426:3; Yabia Omer ibid]; Shvus Yaakov 3:31 and Biur Halacha 426:3 conclude to say without a blessing like this opinion; Rabbi Mordechai Perlow states that he remembers that a number of times they said Kiddush Levana in Lubavitch on the night of the 16^th from a Gemara Sanhedrin

[6] Chasam Sofer ibid that it may even initially be said up until 18 hours past the time of the Rama; The Rebbe in 1961 15^th Sivan said Kiddush Levana 1.5 hours past the time. The Rebbe stated he relies on the Chasam Sofer ibid

[7] The reason: As it takes 18 hours for the effects of the moon to be seen on earth. Thus, the diminishing of the moon is not visible to earth until this time. [Chasam Sofer ibid; See also Shvus Yaakov ibid; Yabia Omer ibid]

[8] Suggestion in Chasam Sofer 102 [Nevertheless, he does not permit it unequivocally as is understood there from the Teshuvah]; Directive of Rebbe Maharash and Rebbe Rashab in Shemuos Vesipurim p. 184 [From the testimony of Reb Yaakov Landau recorded below it is evident that the Rebbe Maharash and Rebbe Rashab allowed saying Kiddush Levana even past the 16^th of the month, and even without using a Gemara. The Rebbe Rashab once said Kiddush Levana 17 days past the molad. It was said with a blessing and not from a Gemara. [Memoirs of Rav Yaakov Landau, brought in Shemuos Vesipurim p. 184 see below]

[9] The reason: The Chasam Sofer 102 defends saying Kiddush Levana with a blessing even within the second half of the month if one receives much joy from this, such as when the moon had not been seen the entire month and one looks forward to seeing it as a good omen. [See Teshuvah there for the exact case of allowance of Chasam Sofer] His reasoning is because it is a blessing of praise to Hashem for the joy and benefit of the moonlight.

[10] Divrei Torah 4:107; Darkei Chaim Veshalom 495; Yeshuos Yaakov ibid in name of Tzadik [although he negates it]; Mor Vohalos Posek in name of Tzadik [although he negates it]; Mishmeres Shalom Kudinav 31:7 in name Bnei Yissachar in name of the Chozeh Milublin; See also Avnei Nezer 383; Taamei Haminhagim p. 199 brings from Derech Pekudecha in name of the Chozeh Melublin that after the time has passed one may nevertheless read the blessing from the Gemara. Alef Lamagen 581:22 concludes from Derech Pekudecha that so is the custom of the world to say it from a Gemara with a blessing after the correct time; Mentioned in words of Rebbe Rashab in Shemuos Vesipurim p. 184; See Sheilas Yaavetz 81 that one may mention Hashem’s name when reading a blessing in the Talmud

Other opinions: Many Poskim forbid reading a blessing with Hashem’s name from a Gemara or Tur. [See M”A 215:5; Birkeiy Yosef 215 that so is custom of elderly Rabbis; Machazik Bracha in name of Tashbatz Katan 419 in name of Maharam, brought in Shaareiy Teshuvah 215:4; P”M 215 A”A 5; M”B 215:14; Yabia Omer 8:42]

[11] Gemara Sanhedrin 42a

[12] Rav Poalim 2:38 and Kaf Hachaim 426:53 that so applies even for Sephardim that they should suspect for the opinion of Rama ibid

[13] As so concludes the M”B in Biur Halacha ibid that one may be lenient like Michaber ibid

[14] Rav Poalim and Kaf Hachaim ibid rule to say without Hashem’s name; Yabia Omer ibid rules to say with Hashem’s name

[15] Hiskashrus 961 writes [Vetzaruch Iyun as to his source] that one may say Kiddush Levana up to 18 hours past the time of the Rama [15 days 12 hours and 22 minutes from the Molad] as rules the Chasam Sofer, however he may not say it anymore once 18 hours have passed. In correspondence with Rav Ginzberg he wrote to me that this was the ruling of Rav Yaakov Landau, as was told to him by his son Rav Eliyahu Landau, that after 18 hours of the time of the Rama one may not be lenient to say it. This is despite the fact that the story mentioned above took place with Rav Yaakov Landau and he received a directive from the Rebbe Rashab to say Kiddush Levana on the night of the 20^th. This story had been authenticated by the Rebbe Rayatz and was passed over his holy eyes prior to its publishing. Nevertheless, in actuality we are not lenient to rule this way. In an earlier volume of Hiskashrus [409] as well as in the glosses of Rav Raskin on the Siddur they wrote one may rely on the above story and recite Kiddush Levana even past the above time.

[16] See glosses of Rav Raskin on Siddur who writes he recalls a directive of the Rebbe to say it from the Gemara when it is being said past the time.

[17] See here https://www.e-education.psu.edu/eme810/node/530 and here https://susdesign.com/sunangle/ ; https://fate.windada.com/cgi-bin/SolarTime_en 

Background: There are two important ways of describing time. “Clock time” is the artificial time that we use in everyday life to standardize our time measurements. It allows people in different locations to use the same time or to easily convert time from one location to another. “Local solar time” (or simply “solar time”) is the time according to the position of the sun in the sky relative to one specific location on the ground. In solar time, the sun is always due south (or north) at exactly noon. This means that someone a few miles east or west of you will realize a slightly different solar time than you, although your clock time is probably the same. For the purpose of calculating local solar time, clock time must modified to compensate for three things: (1) the relationship between the local time zone and the local longitude, (2) daylight savings time, and (3) the earth’s slightly-irregular motion around the sun (corrected for using the equation of time). Local solar time (LSoT) is calculated as follows: LSoT = LST + 4 minutes * (LL – LSTM) + ET Where: LST (local standard time) = Clock time, adjusted for daylight savings time if necessary. LL = The local longitude; positive = East, and negative = West. LSTM = The local standard time meridian, measured in degrees, which runs through the center of each time zone. It can be calculated by multiplying the differences in hours from Greenwich Mean Time by 15 degrees per hour. Positive = East, and negative = West. ET = The equation of time adjustment in minutes.

[18] Brought in Shemuos Vesippurim p. 182; This story was reviewed and authenticated by the Rebbe Rayatz. [See Kfar Chabad 986]

[19] This story took place in 1919, of which Motzei Shabbos was the 18^th of Shevat. The original mistakenly states the 19^th of Shevat.

[20] The story was written by Rav Yaakov Landau.

[21] Shemuos Vesipurim Vol. 2 p. 57

[22] Machazikei Bracha 426:7; Shaareiy Teshuvah 426:9; Nodah Beyehuda 41; See Admur 431:6; See Teshuvos Vehanhagos 1:310; 2:248

and  Piskeiy Teshuvah 489 footnote 16 in name of Shagas Aryeh and Rav Chaim Volozhin that they Davvened Maariv before Kiddush Levana even at a time that there was chance they would lose the opportunity.

[23] See Piskeiy Teshuvos 295:6

[24] Sefer Haminhagim p. 126 [English] regarding Motzei Yom Kippur; Likkut Dinei Rosh Chodesh 12:10

The reason: Perhaps this is because Havdala is more Tadir. [see Poskim in 681 regarding Chanukah]

[25] Nodah Beyehuda 41

[26] The reason: As Kiddush Levana is a more common Mitzvah, and possibly it will not be visible afterwards. [Noda Beyehuda ibid]

[27] Nodeh Beyehuda 41; Machazikei Bracha 426:3; Shaareiy Teshuvah 426:9

[28] Biur Halacha 426 “Velo Tes Zayin Bechlal”

[29] Nodeh Beyehuda 41; Machazikei Bracha 426:4;

[30] Maharil 19 brought in Beis Yosef, Kaf Hachaim 426:60