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Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54)

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	Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Walter Ziobro :: Rate this Message: \| View Threaded \| Show Only this Message Julian Lunation Number I want to introduce a calendar concept which I call the Julian Lunation Number. I hesitate to call it "new" because it is such an obvious concept to my mind, that I cannot imagine that it has not been proposed before this. Nevertheless, I have not found any reference to such a concept. I welcome the information of anyone who can provide evidence of such. The basic idea is to number consecutively all the the complete lunations since the commencement of the Julian date numbering system. In this way, every historical calendrical, or astronomically recorded, lunar month can be uniquely identified for purposes of calendrical conversions, cross-referencing, programming, and comparative chronological studies. Serial lunation numbers came into use with Ernest William Brown, a British astronomer and mathematician who did extensive studies of the motions of the moon. He starting serially numbering all lunations since the new moon of January 17, 1923. Consequently, the number for the lunation from January 23, until February 21 of 2012 is 1102. Additional lunation numbers have been established: Jean Meeus introduced his own lunation number, which commenced with lunation 0 on the first new moon of 2000. The conversion formula is MLN = BLN - 953. Herman Goldstein started his own lunation number, which begins with lunation 0 on January 11, 1001 BCE. The conversion formula is GLN = BLN + 37105. A Hebrew Lunation Number counts the lunations since the beginning of the Hebrew calendar on September 7, 3761 BCE. The formula is HLN = BLN + 71234. There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. In theory, this could be Julian Day 1, since Scaliger incorporated the 19-year Metonic cycle into his numbering scheme. However, since the actual period of the synodic month varies from the calculated lunar month of the Metonic cycle, there is some variance. Using Meeus' length of the average lunar month 29.53058867 =/- 0.25 days, and back calculating from January 17, 1923, I determine that the first new moon occurred on or about Julian Day 9. If anyone has a more precise date, I welcome it for consideration. Consequently, I calculate that the Julian Lunation Number (JLN) would be: JLN = BLN + 82065. Therefore the JLN of Jan 23 - Feb 21, 2012 is 83167 (1102 + 82065). Further: Meeus Lunation Number 0 would be: JLN = (82065 + 953) = 83018 Goldstain Lunation Number 0 would be: JLN = (82065 - 37105) = 44960 Hebrew Lunation Number 1 would be: JLN = (82065 - 71234) = 10831 Islamic Lunation Number 1 would be: JLN + (82065 - 17038) = 65027 -Walter Ziobro From: CALNDR-L automatic digest system <LISTSERV@...> To: CALNDR-L@... Sent: Monday, February 6, 2012 4:00 PM Subject: CALNDR-L Digest - 6 Feb 2012 (#2012-54) ----- Forwarded Message ----- There are 2 messages totaling 90 lines in this issue. Topics of the day: 1. Venus and Uranus (2) Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. Thanks. Looks like it gets a bit closer than that. Using JD = 2455967.625 I get an angular distance of just over 17.32'. That's about half an hour before setting local time here. Victor On Mon, Feb 6, 2012 at 1:31 PM, Helios <suntheorem@...> wrote: Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com.
	Scaliger Lunation Number by Gent, R.H. van (Rob) :: Rate this Message: \| View Threaded \| Show Only this Message Hi, This proposal is not entirely new. In 1978 O.L. Harvey proposed the "Scaliger Lunation Number" (SLN) - which I think is a more appropriate (and less confusing) name - in the following article in _Ciel & Terre_ http://adsabs.harvard.edu/abs/1978C%26T....94..147H He proposed to simply divide the JDN by the (average) length of the lunation although it does make more sense, as you propose, to have the lunation numbers change at New Moon. rvg ________________________________ From: East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Walter Ziobro Sent: 06 February 2012 22:36 To: CALNDR-L@... Subject: Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Julian Lunation Number I want to introduce a calendar concept which I call the Julian Lunation Number. I hesitate to call it "new" because it is such an obvious concept to my mind, that I cannot imagine that it has not been proposed before this. Nevertheless, I have not found any reference to such a concept. I welcome the information of anyone who can provide evidence of such. The basic idea is to number consecutively all the the complete lunations since the commencement of the Julian date numbering system. In this way, every historical calendrical, or astronomically recorded, lunar month can be uniquely identified for purposes of calendrical conversions, cross-referencing, programming, and comparative chronological studies. Serial lunation numbers came into use with Ernest William Brown, a British astronomer and mathematician who did extensive studies of the motions of the moon. He starting serially numbering all lunations since the new moon of January 17, 1923. Consequently, the number for the lunation from January 23, until February 21 of 2012 is 1102. Additional lunation numbers have been established: Jean Meeus introduced his own lunation number, which commenced with lunation 0 on the first new moon of 2000. The conversion formula is MLN = BLN - 953. Herman Goldstein started his own lunation number, which begins with lunation 0 on January 11, 1001 BCE. The conversion formula is GLN = BLN + 37105. A Hebrew Lunation Number counts the lunations since the beginning of the Hebrew calendar on September 7, 3761 BCE. The formula is HLN = BLN + 71234. There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. In theory, this could be Julian Day 1, since Scaliger incorporated the 19-year Metonic cycle into his numbering scheme. However, since the actual period of the synodic month varies from the calculated lunar month of the Metonic cycle, there is some variance. Using Meeus' length of the average lunar month 29.53058867 =/- 0.25 days, and back calculating from January 17, 1923, I determine that the first new moon occurred on or about Julian Day 9. If anyone has a more precise date, I welcome it for consideration. Consequently, I calculate that the Julian Lunation Number (JLN) would be: JLN = BLN + 82065. Therefore the JLN of Jan 23 - Feb 21, 2012 is 83167 (1102 + 82065). Further: Meeus Lunation Number 0 would be: JLN = (82065 + 953) = 83018 Goldstain Lunation Number 0 would be: JLN = (82065 - 37105) = 44960 Hebrew Lunation Number 1 would be: JLN = (82065 - 71234) = 10831 Islamic Lunation Number 1 would be: JLN + (82065 - 17038) = 65027 -Walter Ziobro ________________________________ From: CALNDR-L automatic digest system <LISTSERV@...> To: CALNDR-L@... Sent: Monday, February 6, 2012 4:00 PM Subject: CALNDR-L Digest - 6 Feb 2012 (#2012-54) ----- Forwarded Message ----- There are 2 messages totaling 90 lines in this issue. Topics of the day: 1. Venus and Uranus (2) Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. Thanks. Looks like it gets a bit closer than that. Using JD = 2455967.625 I get an angular distance of just over 17.32'. That's about half an hour before setting local time here. Victor On Mon, Feb 6, 2012 at 1:31 PM, Helios <suntheorem@...> wrote: Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com.
	Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Karl Palmen :: Rate this Message: \| View Threaded \| Show Only this Message Some parts of this message have been removed. Learn more about Nabble's security policy. Dear Walter and Calendar People Walter said The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. This does not make it clear when lunation 1 (or lunation 0) would begin. I’d prefer something like Lunation 1 of the Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. I’m not sure whether it was intended that a new moon were to occur at the Jan 1^st start of the first year of the 19-year cycle of the Julian Cycle, but suppose this were the case. The Metonic Cycle would be fairly accurate if a leap year were dropped from the Julian calendar once every 300 years (rather than 3 times every 400 years as for Gregorian calendar). Given that JD 0 is in year -4712, then 22 leap days would have been dropped till 1888 and so a JD numbering based on such a calendar would begin about 22 days late. This would suggest new moon on JD 22, which contradicts the JD 9 mentioned for this, but then the supposition I made may be wrong or perhaps it’s a full moon at rather than new moon in the supposition. Also the mean synodic month may have been around 1/100,000 day longer in the past leading to the estimated new moon day to be about day earlier (i.e. JD 8). This suggests that a more accurate date is not needed for the purpose of checking the lunation numbering. Also There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. BLN=1102 so ILN=18140 implying 8^th month of Islamic year 1512, which is not correct. The correct value is 17187. So making ILN = BLN + 16085 assuming the BLN 1102 is correct. I see 17038 = 16085 + 953, hence ILN = MLN + 17038. In my lunar yerm calendar, this month is the 8^th month of the 12^th yerm of the 21^st cycle and counting months from the first month of the first cycle is ILN + 2, which is 20850+189 = 17189 for this lunar month. Karl 12(08(16 From:* East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Walter Ziobro Sent: 06 February 2012 21:36 To: CALNDR-L@... Subject: Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Julian Lunation Number I want to introduce a calendar concept which I call the Julian Lunation Number. I hesitate to call it "new" because it is such an obvious concept to my mind, that I cannot imagine that it has not been proposed before this. Nevertheless, I have not found any reference to such a concept. I welcome the information of anyone who can provide evidence of such. The basic idea is to number consecutively all the the complete lunations since the commencement of the Julian date numbering system. In this way, every historical calendrical, or astronomically recorded, lunar month can be uniquely identified for purposes of calendrical conversions, cross-referencing, programming, and comparative chronological studies. Serial lunation numbers came into use with Ernest William Brown, a British astronomer and mathematician who did extensive studies of the motions of the moon. He starting serially numbering all lunations since the new moon of January 17, 1923. Consequently, the number for the lunation from January 23, until February 21 of 2012 is 1102. Additional lunation numbers have been established: Jean Meeus introduced his own lunation number, which commenced with lunation 0 on the first new moon of 2000. The conversion formula is MLN = BLN - 953. Herman Goldstein started his own lunation number, which begins with lunation 0 on January 11, 1001 BCE. The conversion formula is GLN = BLN + 37105. A Hebrew Lunation Number counts the lunations since the beginning of the Hebrew calendar on September 7, 3761 BCE. The formula is HLN = BLN + 71234. There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. In theory, this could be Julian Day 1, since Scaliger incorporated the 19-year Metonic cycle into his numbering scheme. However, since the actual period of the synodic month varies from the calculated lunar month of the Metonic cycle, there is some variance. Using Meeus' length of the average lunar month 29.53058867 =/- 0.25 days, and back calculating from January 17, 1923, I determine that the first new moon occurred on or about Julian Day 9. If anyone has a more precise date, I welcome it for consideration. Consequently, I calculate that the Julian Lunation Number (JLN) would be: JLN = BLN + 82065. Therefore the JLN of Jan 23 - Feb 21, 2012 is 83167 (1102 + 82065). Further: Meeus Lunation Number 0 would be: JLN = (82065 + 953) = 83018 Goldstain Lunation Number 0 would be: JLN = (82065 - 37105) = 44960 Hebrew Lunation Number 1 would be: JLN = (82065 - 71234) = 10831 Islamic Lunation Number 1 would be: JLN + (82065 - 17038) = 65027 -Walter Ziobro From: CALNDR-L automatic digest system <LISTSERV@...> To: CALNDR-L@... Sent: Monday, February 6, 2012 4:00 PM Subject: CALNDR-L Digest - 6 Feb 2012 (#2012-54) ----- Forwarded Message ----- There are 2 messages totaling 90 lines in this issue. Topics of the day: 1. Venus and Uranus (2) Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. Thanks. Looks like it gets a bit closer than that. Using JD = 2455967.625 I get an angular distance of just over 17.32'. That's about half an hour before setting local time here. Victor On Mon, Feb 6, 2012 at 1:31 PM, Helios <suntheorem@...> wrote: Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. -- Scanned by iCritical.
	Re: Scaliger Lunation Number by Karl Palmen :: Rate this Message: \| View Threaded \| Show Only this Message Dear Calendar People I think dividing the JDN of the full moon day of the lunation by the mean lunation length and rounding up will work for a very long time. For example, this lunation has full moon today JDN 2455965 and so dividing by 29.5305388 gives 83166.81... so making it lunation 83167. Running Calendrica http://emr.cs.iit.edu/home/reingold/calendar-book/Calendrica.html For JDN 0, shows the 22nd day of a Chinese lunar month and JDN 8 shows the first day of a Chinese month. Karl 12(08(16 -----Original Message----- From: East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Gent, R.H. van (Rob) Sent: 07 February 2012 11:41 To: CALNDR-L@... Subject: Scaliger Lunation Number Hi, This proposal is not entirely new. In 1978 O.L. Harvey proposed the "Scaliger Lunation Number" (SLN) - which I think is a more appropriate (and less confusing) name - in the following article in _Ciel & Terre_ http://adsabs.harvard.edu/abs/1978C%26T....94..147H He proposed to simply divide the JDN by the (average) length of the lunation although it does make more sense, as you propose, to have the lunation numbers change at New Moon. rvg ________________________________ From: East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Walter Ziobro Sent: 06 February 2012 22:36 To: CALNDR-L@... Subject: Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Julian Lunation Number I want to introduce a calendar concept which I call the Julian Lunation Number. I hesitate to call it "new" because it is such an obvious concept to my mind, that I cannot imagine that it has not been proposed before this. Nevertheless, I have not found any reference to such a concept. I welcome the information of anyone who can provide evidence of such. The basic idea is to number consecutively all the the complete lunations since the commencement of the Julian date numbering system. In this way, every historical calendrical, or astronomically recorded, lunar month can be uniquely identified for purposes of calendrical conversions, cross-referencing, programming, and comparative chronological studies. Serial lunation numbers came into use with Ernest William Brown, a British astronomer and mathematician who did extensive studies of the motions of the moon. He starting serially numbering all lunations since the new moon of January 17, 1923. Consequently, the number for the lunation from January 23, until February 21 of 2012 is 1102. Additional lunation numbers have been established: Jean Meeus introduced his own lunation number, which commenced with lunation 0 on the first new moon of 2000. The conversion formula is MLN = BLN - 953. Herman Goldstein started his own lunation number, which begins with lunation 0 on January 11, 1001 BCE. The conversion formula is GLN = BLN + 37105. A Hebrew Lunation Number counts the lunations since the beginning of the Hebrew calendar on September 7, 3761 BCE. The formula is HLN = BLN + 71234. There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. In theory, this could be Julian Day 1, since Scaliger incorporated the 19-year Metonic cycle into his numbering scheme. However, since the actual period of the synodic month varies from the calculated lunar month of the Metonic cycle, there is some variance. Using Meeus' length of the average lunar month 29.53058867 =/- 0.25 days, and back calculating from January 17, 1923, I determine that the first new moon occurred on or about Julian Day 9. If anyone has a more precise date, I welcome it for consideration. Consequently, I calculate that the Julian Lunation Number (JLN) would be: JLN = BLN + 82065. Therefore the JLN of Jan 23 - Feb 21, 2012 is 83167 (1102 + 82065). Further: Meeus Lunation Number 0 would be: JLN = (82065 + 953) = 83018 Goldstain Lunation Number 0 would be: JLN = (82065 - 37105) = 44960 Hebrew Lunation Number 1 would be: JLN = (82065 - 71234) = 10831 Islamic Lunation Number 1 would be: JLN + (82065 - 17038) = 65027 -Walter Ziobro ________________________________ From: CALNDR-L automatic digest system <LISTSERV@...> To: CALNDR-L@... Sent: Monday, February 6, 2012 4:00 PM Subject: CALNDR-L Digest - 6 Feb 2012 (#2012-54) ----- Forwarded Message ----- There are 2 messages totaling 90 lines in this issue. Topics of the day: 1. Venus and Uranus (2) Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. Thanks. Looks like it gets a bit closer than that. Using JD = 2455967.625 I get an angular distance of just over 17.32'. That's about half an hour before setting local time here. Victor On Mon, Feb 6, 2012 at 1:31 PM, Helios <suntheorem@...> wrote: Dear Victor, The site "Your Sky", a virtual telescope http://www.fourmilab.ch/yoursky/help/telcontrols.html tabulates planet data for given time. I plug in JD = 2455967.72500 and then RA's match. Then the declination differs by 0° 20.4' with Uranus the lesser. -- View this message in context: http://old.nabble.com/Venus-and-Uranus-tp33273086p33273833.html Sent from the Calndr-L mailing list archive at Nabble.com. -- Scanned by iCritical.
	Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Karl Palmen :: Rate this Message: \| View Threaded \| Show Only this Message Some parts of this message have been removed. Learn more about Nabble's security policy. From: Palmen, Karl (STFC,RAL,ISIS) Sent: 08 February 2012 13:17 To: 'Walter Ziobro' Subject: RE: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Dear Walter and Calendar People From: Walter Ziobro [mailto:petersonwalter@...] Sent: 07 February 2012 21:58 To: Palmen, Karl (STFC,RAL,ISIS) Subject: Re: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Actually, you have bought to my attention a couple of errors in my post, for which I thank you. When Scalinger devised the Julian Day scheme, he back calculated the Metonic cycles from 25 January 1 BCE (Julian), which was a new moon, and the epoch of the Golden Numbers. There would have been 248 Metonic cycles from 25 January 1 BCE to 25 January 4713 BCE (Julian), which, if the Metonic cycle were in perfect sync with the Julian calendar would have been a new moon. But, if you drop a leap year day from the Julian calendar every 300 years, as you suggest, then the difference will amount to about 16 days in 4712 years, implying, if I have it correctly, that the new moon in January 4713 BCE would have been on or about January 9, if there are no corrections to the Julian leap year rule, which is the date that I obtained by back calculating from Brown's Lunation 1 in January 1923, using Meeus' average length of the synodic month. If the Julian Calendar were corrected as stated by dropping a leap day every 300 years and with agreement on 1 BCE, the 16 day difference would cause 25 January 4713 BCE of the amended calendar to occur on 10 February 4713 BCE of the Julian calendar, so suggesting a new moon on 11^th or 12^th of January rather than the 9^th or 8^th. The difference could be explained by the new moon being a visible crescent. Aslo, I have not been able to confirm your conversion formula for the Islamic Lunation Number, but I shall recheck my calculations. I think Walter did the calculation on MLN thinking it was BLN. Karl 12(08(17 Thank you. -Walter Ziobro From: "karl.palmen@..." <karl.palmen@...> To: petersonwalter@...; CALNDR-L@... Sent: Tuesday, February 7, 2012 8:32 AM Subject: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Dear Walter and Calendar People Walter said The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. This does not make it clear when lunation 1 (or lunation 0) would begin. I’d prefer something like Lunation 1 of the Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. I’m not sure whether it was intended that a new moon were to occur at the Jan 1^st start of the first year of the 19-year cycle of the Julian Cycle, but suppose this were the case. The Metonic Cycle would be fairly accurate if a leap year were dropped from the Julian calendar once every 300 years (rather than 3 times every 400 years as for Gregorian calendar). Given that JD 0 is in year -4712, then 22 leap days would have been dropped till 1888 and so a JD numbering based on such a calendar would begin about 22 days late. This would suggest new moon on JD 22, which contradicts the JD 9 mentioned for this, but then the supposition I made may be wrong or perhaps it’s a full moon at rather than new moon in the supposition. Also the mean synodic month may have been around 1/100,000 day longer in the past leading to the estimated new moon day to be about day earlier (i.e. JD 8). This suggests that a more accurate date is not needed for the purpose of checking the lunation numbering. Also There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. BLN=1102 so ILN=18140 implying 8^th month of Islamic year 1512, which is not correct. The correct value is 17187. So making ILN = BLN + 16085 assuming the BLN 1102 is correct. I see 17038 = 16085 + 953, hence ILN = MLN + 17038. In my lunar yerm calendar, this month is the 8^th month of the 12^th yerm of the 21^st cycle and counting months from the first month of the first cycle is ILN + 2, which is 20850+189 = 17189 for this lunar month. Karl 12(08(16 From:* East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Walter Ziobro Sent: 06 February 2012 21:36 To: CALNDR-L@... Subject: Re: CALNDR-L Digest - 6 Feb 2012 (#2012-54) Julian Lunation Number I want to introduce a calendar concept which I call the Julian Lunation Number. I hesitate to call it "new" because it is such an obvious concept to my mind, that I cannot imagine that it has not been proposed before this. Nevertheless, I have not found any reference to such a concept. I welcome the information of anyone who can provide evidence of such. The basic idea is to number consecutively all the the complete lunations since the commencement of the Julian date numbering system. In this way, every historical calendrical, or astronomically recorded, lunar month can be uniquely identified for purposes of calendrical conversions, cross-referencing, programming, and comparative chronological studies. Serial lunation numbers came into use with Ernest William Brown, a British astronomer and mathematician who did extensive studies of the motions of the moon. He starting serially numbering all lunations since the new moon of January 17, 1923. Consequently, the number for the lunation from January 23, until February 21 of 2012 is 1102. Additional lunation numbers have been established: Jean Meeus introduced his own lunation number, which commenced with lunation 0 on the first new moon of 2000. The conversion formula is MLN = BLN - 953. Herman Goldstein started his own lunation number, which begins with lunation 0 on January 11, 1001 BCE. The conversion formula is GLN = BLN + 37105. A Hebrew Lunation Number counts the lunations since the beginning of the Hebrew calendar on September 7, 3761 BCE. The formula is HLN = BLN + 71234. There is an Islamic Lunation Number which commences on July 16, 622. ILN = BLN + 17038. The Julian Lunation Number (JLN) would commence on the first new moon that falls on a positive Julian day number. In theory, this could be Julian Day 1, since Scaliger incorporated the 19-year Metonic cycle into his numbering scheme. However, since the actual period of the synodic month varies from the calculated lunar month of the Metonic cycle, there is some variance. Using Meeus' length of the average lunar month 29.53058867 =/- 0.25 days, and back calculating from January 17, 1923, I determine that the first new moon occurred on or about Julian Day 9. If anyone has a more precise date, I welcome it for consideration. Consequently, I calculate that the Julian Lunation Number (JLN) would be: JLN = BLN + 82065. Therefore the JLN of Jan 23 - Feb 21, 2012 is 83167 (1102 + 82065). Further: Meeus Lunation Number 0 would be: JLN = (82065 + 953) = 83018 Goldstain Lunation Number 0 would be: JLN = (82065 - 37105) = 44960 Hebrew Lunation Number 1 would be: JLN = (82065 - 71234) = 10831 Islamic Lunation Number 1 would be: JLN + (82065 - 17038) = 65027 -Walter Ziobro
	Re: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Helios :: Rate this Message: \| View Threaded \| Show Only this Message Dear Calendar People, The reference date I use for mean lunations is March 21, 1985 NOON, BLN = 770, JD = 2446146 Compare this to January 6, 2000 AD at 14:20:44 BLN = 953, JD = 2451550.0977315 Verily, [ 2451550.0977315 - 2446146 ] / 183 = 29.5305887 days ( I lost the reference for this, though Irv B. cites it on his page)
	Re: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Brillig :: Rate this Message: \| View Threaded \| Show Only this Message Do you use it because it's a noon lunation? Victor On Thu, Feb 9, 2012 at 2:25 AM, Helios <suntheorem@...> wrote: > Dear Calendar People, > The reference date I use for mean lunations is > March 21, 1985 NOON, BLN = 770, JD = 2446146 > Compare this to > January 6, 2000 AD at 14:20:44 BLN = 953, JD = 2451550.0977315 > Verily, > [ 2451550.0977315 - 2446146 ] / 183 = 29.5305887 days > ( I lost the reference for this, though Irv B. cites it on his page) > > -- > View this message in context: http://old.nabble.com/Re%3A-CALNDR-L-Digest---6-Feb-2012-%28-2012-54%29-tp33274919p33291580.html > Sent from the Calndr-L mailing list archive at Nabble.com.
	Re: Lunation Numbering RE: CALNDR-L Digest - 6 Feb 2012 (#2012-54) by Helios :: Rate this Message: \| View Threaded \| Show Only this Message Brillig wrote: Do you use it because it's a noon lunation? Victor Yes. Naturally. Noon is the bull's eye. Starting as such will maximize the probability that ecclesiastical months ( months of either 29 or 30 days ) will match the day of the synodic month. This, provided that ecclesiastical months are arranged symmetrically ( or nearly ).