1,315. Calculating the Angle of the Course

Hilchos Kiddush HaChodesh 15:6

If the proper course is ten degrees, the angle of the course will be 50 minutes; if the proper course is 20 degrees, the angle will be 1 degree, 38 minutes; if 30 degrees, the angle will be 2 degrees, 24 minutes; if 40 degrees, the angle will be 3 degrees, 6 minutes; if 50, the angle will be 3 degrees, 44 minutes; if 60 degrees, the angle will be 4 degrees, 16 minutes; if 70 degrees, the angle will be 4 degrees, 41 minutes; if 80 degrees, the angle will be 5 degrees; if 90, then 5 degrees, 5 minutes; if 100, then 5 degrees, 8 minutes; if 110, then 4 degrees, 59 minutes; if 120, then 4 degrees, 40 minutes; if 130, then 4 degrees, 11 minutes; if 140, then 3 degrees, 33 minutes; if 150, then 213 degrees, 48 minutes; if 160, then 1 degree, 56 minutes; if the proper course is 170 degrees, the angle of the course will be 59 minutes. If it is exactly 180 degrees, it will not have an angle. Rather, the moon’s average position and its actual position will be the same, as we have already stated.

Hilchos Kiddush HaChodesh 15:7

If the proper course is more than 180 degrees, subtract it from 360 to get the angle, as one does when calculating the course of the sun (see chapter 13). Similarly, if the proper course includes ones in addition to tens, take from the greater of the two “ones” (see 13:7). The process for calculating the angle for the course of the sun is also used to calculate the angle of the moon’s proper course.