Chinese Calendar Algorithm - Year 1901 to 2100 - v4.15, by Herong Yang
Corrections on the Astronomical Data
This section discusses some corrections on the astronomical data in my program used to generated Chinese calendars.
Thanks to "lsa", who reported the following errors on Principle and Sectional Terms:
2014: Mar 5 -> 6 2021: Apr 5 -> 4 2032: Apr 5 -> 4 2051: Mar 21 -> 20 2071: Mar 21 -> 20 2081: May 21 -> 20 2083: Feb 4 -> 3 2084: Mar 20 -> 19 2094: Jun 6 -> 5
There are two ways to validates those corrections:
Error 1 - 2014: Mar 5 -> 6 - According to Keith's program, the sectional term in March of 2014 should be 2014-03-05 16:00 GMT, which is 2014-03-06 00:00 WST (China timezone). So this is a borderline case. We should keep it to Mar 5 in Chinese calendar, and waiting for better validations.
year : 2014
month : 3
day : 5
hour UT : 16
minute : 0
Position of Sun
===============
days : 5177.16667
longitude : 345.00
RA : 23.079
DEC : -5.91
distance : 0.99189
eq time : -11.47
Error 2 - 2021: Apr 5 -> 4 - According to Keith's program, the sectional term in April of 2021 should be 2021-04-04 13:30 GMT, which is 2021-04-04 21:30 WST (China timezone). So this is definitely an error. We should change it to Apr 4 in Chinese calendar.
year : 2021
month : 4
day : 4
hour UT : 13
minute : 30
Position of Sun
===============
days : 7764.06250
longitude : 15.00
RA : 0.921
DEC : 5.91
distance : 1.00022
eq time : -2.91
Error 3 - 2032: Apr 5 -> 4 - According to Keith's program, the sectional term in April of 2032 should be 2032-04-04 05:15 GMT, which is 2032-04-04 13:15 WST (China timezone). So this is definitely an error. We should change it to Apr 4 in Chinese calendar.
year : 2032
month : 4
day : 4
hour UT : 5
minute : 15
Position of Sun
===============
days :11781.71875
longitude : 15.00
RA : 0.921
DEC : 5.91
distance : 1.00016
eq time : -2.91
Error 4 - 2051: Mar 21 -> 20 - According to Fred's table, the principal term in March of 2051 should be 2051-03-20 15:58 GMT, which is 2051-03-20 23:58 WST (China timezone). So this is also a borderline case. We should keep it to Mar 5 in Chinese calendar, and waiting for better validations.
2051= 20 15:58, 21 09:17, 23 01:26, 21 22:33
Error 5 - 2071: Mar 21 -> 20 - According to Fred's table, the principal term in March of 2071 should be 2071-03-20 12:36 GMT, which is 2071-03-20 20:36 WST (China timezone). So this is definitely an error. We should change it to March 20 in Chinese calendar.
2071= 20 12:36, 21 05:21, 22 21:39, 21 19:05
Error 6 - 2081: May 21 -> 20 - According to Keith's program, the principal term in May of 2081 should be 2081-05-20 07:30 GMT, which is 2081-05-20 15:30 WST (China timezone). So this is definitely an error, even Keith's program is less accurate for years > 2050. We should change it to May 20 in Chinese calendar.
year : 2081
month : 5
day : 20
hour UT : 7
minute : 30
Position of Sun
===============
days :29724.81250
longitude : 60.00
RA : 3.854
DEC : 20.14
distance : 1.01182
eq time : 3.32
Error 7 - 2083: Feb 4 -> 3 - According to Keith's program, the sectional term in February of 2083 should be 2083-02-03 16:00 GMT, which is 2083-02-04 00:00 WST (China timezone). So this is also a borderline case. We should keep it to Feb 4 in Chinese calendar, waiting for better validations, since Keith's program is less accurate for years > 2050.
year : 2083
month : 2
day : 3
hour UT : 16
minute : 0
Position of Sun
===============
days :30349.16667
longitude : 315.00
RA : 21.164
DEC : -16.33
distance : 0.98555
eq time : -13.71
Error 8: 2084: Mar 20 -> 19 - According to Fred's table, the principal term in March of 2084 should be 2084-03-19 15:58 GMT, which is 2084-03-19 23:58 WST (China timezone). So this is also a borderline case. We should keep it to Mar 20 in Chinese calendar, waiting for better validations.
2084= 19 15:58, 20 08:39, 22 00:58, 20 22:40
Error 9 - 2094: Jun 6 -> 5 - According to Keith's program, the sectional term in June of 2094 should be 2094-06-05 02:10 GMT, which is 2094-06-05 10:10 WST (China timezone). So this is definitely an error, even Keith's program is less accurate for years > 2050. We should change it to Jun 6 in Chinese calendar.
year : 2094
month : 6
day : 5
hour UT : 2
minute : 10
Position of Sun
===============
days :34488.59028
longitude : 75.00
RA : 4.915
DEC : 22.58
distance : 1.01447
eq time : 1.29
So there are only 5 errors, which were actually introduced by some changes I have made to the original astronomical data. In other words, the original data was correct. I have removed those changes from my Chinese calendar generation program used in this book.
2021: Apr 5 -> 4 21:30 WST 2032: Apr 5 -> 4 13:15 WST 2071: Mar 21 -> 20 20:36 WST 2081: May 21 -> 20 15:30 WST 2094: Jun 6 -> 5 10:10 WST
Table of Contents
Chinese Calendar Background Information
►Chinese Calendar Algorithm and Program
The Gregorian Calendar Algorithm
The Chinese Calendar Algorithm
Chinese Calendar Program in java
How to Use Chinese Calendar Program
Chinese Calendar Format and Notations
►Corrections on the Astronomical Data
Chinese Calendars: Year 1901 to 1910
Chinese Calendars: Year 1911 to 1920
Chinese Calendars: Year 1921 to 1930
Chinese Calendars: Year 1931 to 1940
Chinese Calendars: Year 1941 to 1950
Chinese Calendars: Year 1951 to 1960
Chinese Calendars: Year 1961 to 1970
Chinese Calendars: Year 1971 to 1980
Chinese Calendars: Year 1981 to 1990
Chinese Calendars: Year 1991 to 2000
Chinese Calendars: Year 2001 to 2010
Chinese Calendars: Year 2011 to 2020
Chinese Calendars: Year 2021 to 2030
Chinese Calendars: Year 2031 to 2040
Chinese Calendars: Year 2041 to 2050
Chinese Calendars: Year 2051 to 2060
Chinese Calendars: Year 2061 to 2070
Chinese Calendars: Year 2071 to 2080
Chinese Calendars: Year 2081 to 2090