eclipse-year

The SYNODIC revolution periods of The Lunar Perigee and the Lunar Node are calculated in the following manner;-

Earth’s orbital period = 365.256 Earth days. (See Section 2 of this appendix.)

The synodic revolution period of The Lunar Perigee =

1 ÷ [(1 ÷ 365.256) – (1 ÷ 3231.492837)] = 411.802 Earth days.

and:-

The synodic revolution period of The Lunar Node =

1 ÷ [(1 ÷ 365.256) PLUS (1 ÷ 6798.375113)] = 346.63249 Earth days. (For a more accurate value for The Eclipse Year, scroll down this page.

Actually, it is listed as The Eclipse Year (node to node) – 346.620 Earth days. To substantiate this, here is a scan from Collins Dictionary of Astronomy, by Daintith and Gould, published by Collins, 2006, pages 127 to 128 – entry “eclipse year”

A more accurate value for The Eclipse Year is given on page C2 of the Astronomical Almanac for 2014. here is a scan from this page:-