The Lunar Bodhi Day for 2018 is on January 13, 2019.

Here’s the explanation:

Bodhi Day is defined as the 8th day of the 12th Moon of the year. That’s how it’s described as the morning Siddhartha Gautama awoke from his deep meditation roughly 2500 years ago.

There are several ways to interpret the “12th Moon of the year”. The Eternal Fishnu said we should consider that to mean the 12th New Moon on the Chinese Calendar. The Chinese New Year for 2018 began on the New Moon that occurred on February 16, 2018.

Why the Chinese Lunar calendar? Simply because it’s a widely used lunar calendar, and close enough to Bodhgaya, India, the site of the Bodhi Tree where Siddhartha Gautama’s Bodhi Day happened.

If you looked up the lunar calendars, such as on Calendar-12.com,  you may see a few little inconsistencies to what I’m saying in this blog.

One has to do with time zones. Lunar calendars on the Internet are usually time-zone sensitive today, so the days may be different. For example, the 12th New Moon of 2018 starts on January 5, 2019 at 6:29pm U.S. Mountain time. But it’s well into January 6 in Bodhgaya, India (11 and a half hours ahead of U.S. Mountain time).

Another is “leap year” in Lunar calendars. As we know, the Lunar periods are around 30 days, which means 12 moons is about 360 days. After a while, those approximately 5 day difference with the 365 day year adds up. There is a need for “leap year”, which means some years will have 13 moons.

Last year, 2017 was one of those “Chinese Leap Years”. The Chinese lunar year had 13 moons. So the first new moon of the Gregorian 2018 calendar, January 16, 2018, belongs to the Chinese Lunar calendar of 2017.

However, the “standardized” Bodhi Day, which is what I call the “secular”, is on December, 8, 2018. That is, the 8th Day of the 12th Month of the year. It’s mostly the day chosen for celebration in Japan.