Blue Moon Explained: Why This Rare Lunar Event Happens More Often | WION Podcast

Added: 2026-05-10

[00:00:00]Welcome to the We On Podcast, where we explore fascinating stories and ideas from various fields. In this episode, we uncover the mystery behind the blue moon and explore why this famous lunar event is not as rare as many people believe.

[00:00:16]For centuries, this unusual lunar event has carried mystery, myths, and confusion across different cultures. The second full moon of May will be a blue moon, believed to be named so because of its rarity. However, the name was not coined for this particular full moon, but instead for the third moon in a season that will also have a fourth one, also very rare.

[00:00:42]The phrase once in a blue moon is based on the celestial event to describe something that would not happen easily and commonly.

[00:00:51]While we believe that blue moon means a rare moon, it is not limited to just one type of full moon. In fact, it never started as a term used in the conventional sense we know of today.

[00:01:03]A writer of a major astronomy magazine made a mistake in a 1956 article, giving the world this commonly known blue moon.

[00:01:12]So, which is the original blue moon?

[00:01:16]This is the blue moon that we will have on May 30, 31, 2026.

[00:01:21]The first full moon of May happened on May 1st, which was a flower full micro moon.

[00:01:27]When the same month has a second full moon, it is known as a blue moon.

[00:01:32]This month is seeing a rare double lunar display.

[00:01:36]This is the full moon for which farmers and astronomers traditionally use the term.

[00:01:41]Each season comprises three months, and each month has a full moon.

[00:01:46]But sometimes you can have four full moons in one season.

[00:01:50]When this happens, we get a blue moon.

[00:01:53]However, instead of the fourth full moon, the third one is called a blue moon.

[00:02:00]The reason for a blue moon, or 13 full moons in 12 months, comes down to a simple mismatch between the lunar cycle and our solar calendar.

[00:02:10]A typical solar year has about 365 days, while a lunar year, made up of 12 full lunar cycles, lasts only around 354 days.

[00:02:21]This 11-day gap slowly builds over time, and roughly every 2.7 years it creates an extra full moon in the calendar.

[00:02:31]The next calendar month blue moon will appear on May 30th, 2026.

[00:02:36]Astronomers can accurately predict these events, which occur about seven times every 19 years.

[00:02:43]In recent years, calendar month blue moons appeared on March 31st, 2018, October 31st, 2020, and August 31st, 2023.

[00:02:53]Looking ahead, the phenomenon will return on May 31st, 2026, followed by December 31st, 2028, September 30th, 2031, July 31st, 2034, and January 31st, 2037. Seasonal blue moons happen because there are 235 full moons, but only 76 astronomical seasons within the 19-year Metonic cycle. As a result, an extra full moon occasionally appears in a single season, creating what is known as a seasonal blue moon. Like the calendar month blue moon, this phenomenon also occurs around seven times every 19 years.

[00:03:30]The next seasonal blue moons are expected on May 20th, 2027, and August 24th, 2029. In the years that follow, the rare event will return on August 21st, 2032, May 22nd, 2035, May 18th, 2038, August 22nd, 2040, and August 20th, 2043.

[00:03:48]Moons that signal the start or end of a season have specific names, such as the harvest moon.

[00:03:54]If the fourth moon were called the blue moon, the named moons would be pushed into the wrong season.

[00:03:59]Having the third full moon be known as the blue moon ensures that the last one of the season retains its proper name.

[00:04:06]Thanks for tuning in to this incredible story.

[00:04:09]If this episode resonated with you, don't forget to hit the like and subscribe button for more captivating stories to come. Stay tuned.