The 'Rarest Full Moon Of 2021' Will Rise This Weekend & It Won't Happen Again For Years

Eyes to the skies to see the full blue moon!

Senior Writer

There will be a seasonal full blue moon over Canada this weekend and another one like it won't be around again for years.

You'll be able to spot it on August 22 and according to The Weather Network, it's the "rarest full moon of 2021" because not only is it a blue moon but it's also the first one to happen in the summer in five years.

The traditional definition of a blue moon is the third full moon in a season that has four full moons. Typically a season only has three full moons but about every three years, there's an additional one.

There is another definition of a blue moon: the second full moon in a single month. While that's the more popular one, it's actually a mistake and misinterpretation of the traditional definition.

It's been a while since a seasonal blue moon happened, and the last one was back on May 18, 2019. Before this, the last time there were four full moons in the summer was even further back in 2016, with the blue moon rising on August 18 of that year.

While the moon won't actually look blue, it's probably worth checking out because the next seasonal blue moon and the next summer one will be three years from now on August 19, 2024.

  • Senior Writer

    Lisa Belmonte (she/her) is a Senior Writer with Narcity Media. After graduating with a Bachelor of Journalism from Toronto Metropolitan University (formerly Ryerson University), she joined the Narcity team. Lisa covers news and notices from across the country from a Canada-wide perspective. Her early coverage of the COVID-19 pandemic earned Narcity its first-ever national journalism award nomination.

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