# 'Blue Moons' in 30-day months?

**URL:** <https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959>\
**Category:** Factual Questions\
**Created:** [July 1, 2015, 3:25pm UTC](https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959 "2015-07-01T15:25:18Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [July 1, 2015, 3:25pm UTC](https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959/1 "2015-07-01T15:25:18Z")

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Yeah, I’m aware of the origin an evolution of the term ‘Blue Moon.’ For the purpose of this question, I’m referring to two full Moons in a calendar month.

According to [the wiki on Blue Moons](https://en.wikipedia.org/wiki/Blue_moon), all of the ones between 2009 and 2021 have been in 31-day months. When was the last and next time it will be in a 30-day month?

(I think I need a hobby.)

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**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\
**Post date:** [July 1, 2015, 4:03pm UTC](https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959/2 "2015-07-01T16:03:27Z")

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June 2007 was the most recent 30 day month with a blue moon.

The next will be September 2031.

[Cite](http://home.hiwaay.net/~krcool/Astro/moon/fullmoon.htm)

I need a hobby, too.

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [July 1, 2015, 4:09pm UTC](https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959/3 "2015-07-01T16:09:22Z")

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Thanks!

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**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\
**Post date:** [July 1, 2015, 4:47pm UTC](https://boards.straightdope.com/t/blue-moons-in-30-day-months/723959/4 "2015-07-01T16:47:30Z")

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[And no way to have it on a February, even during a leap year.](http://www.astronomycafe.net/qadir/q1208.html)