%OP%TNT
%OP%BON
%OP%JUY
%OP%WRY
%OP%PL60
%OP%DP2
%OP%HM0
%OP%FM0
%OP%BM0
%OP%LM4
%CO:A,0,0%
%V%%R%4.1.88
%CO:B,11,76%
   DATE
  ------
%V%%R%1.1.94
 ---------
%V%%R%"DAY"
           

"Full moon" is defined as the time when all 100%PC% of the moon's disc is seen 
 to be illuminated by the sun.

%JL%The mean time between these events is 29 days, 12 hours, 44 mins and 2.9 
secs! but differences will vary from this mean by several hours.

%JL%I thought it might be interesting to construct a method of determining the 
%JR%date of the full moon in any month, any year.  It might also interest 
%JL%others, perhaps in a semi-serious vein - will it be full moon on our son's 
%JR%21st birthday barbecue or when we drive overnight to the cross-Channel 
%JL%ferry? - or check up on a friend's seemingly tall story about a midnight 
escapade?

%JL%I have checked the accuracy with 1938, 1953, 1988 and 1991 Whitaker's 
%JR%Almanacks.  I also know that it was "full moon" when Coventry was bombed 
(14.11.1940) and on "D-day" (6.6.1944) - these check out.  

%JL%Very occassionaly the day of the month will vary one day from the dates in 
%JL%diaries and almanacks.  It is just a question of which side of midnight the 
%JL%mean cycle ocurs and the deviation from the mean at that time.  
%JR%Occasionally there will be two dates in the month - enter 1.10.93 to see.

%H1%Procedure%H1%  -  enter the date for the month and year required, in the form
%JR%              1.1.1840  1.9.40  1.6.93  1.6.2006 - ALWAYS the 1st day of 
              the month.  The day of the full moon in that month is shown.

              If you get an error in Slot B4 - press <> (diamond) and X 
                before entering your date and all will be well.

Note - The Z88's calendar is not correct for any month previous to 10/1752. 
%JL%       It takes no account of the eleven "lost days" in September of 
       that year when the Gregorian calendar replaced the Julian calendar.
          Also note that this program is only valid for the U.K.

%JL%and - when you have memorised the above, or printed it, you can reduce the
%JL%        size of the program to just over 600 bytes by deleting these notes.

%R%Jack Lawrie (4635)  15 Sycamore Grove  Southam  Leamington Spa  CV33 0EY
%R%Tel: 0926 812884
%CO:C,0,30%
%V%%R%%D0%B4-A2
%V%%R%%D2%C2/29.5306
%V%%R%%D2%C3-INT(C3)
%V%%R%29.5306*(1-C4)+1.3
%CO:D,3,64%




%V%%R%%D0%INT(C5)
%CO:E,0,24%%CO:F,0,12%%CO:G,11,40%



%V%%R%IF(D6=30,"DAY 1 AND","          ")
OF THIS MONTH.
%V%%R%IF(D6=1,"AND DAY 30","")
%CO:H,3,0%%CO:I,12,45% 
            FULL MOON CALCULATOR
            --------------------
               J.LAWRIE(4635)
              
              See notes below.
%CO:J,12,50%%CO:K,12,40%%CO:L,12,0%