A rare Blue Moon will be visible this weekend, while Mars shines its brightest since 2003

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published 20 May 2016

That old saying about something happening "once in a blue moon" actually has a scientific back story. A rare astrological phenomenon known as a "Blue Moon" is happening this weekend, and you'll probably be able to catch a glimpse of it even without a telescope. Mars is currently in retrograde and will be positioned directly opposite the Earth, meaning us earthlings will be directly in between Mars and the sun. This will make the red planet more visible and bright to the human eye than usual, and the brightest it's been since 2003.

According to the Miami Herald, if on Saturday night you look to the southeastern part of the sky, there's a chance you will catch a glimpse of this rare Blue Moon, while Mars will be glowing a rusty-orange color. But be forewarned: A Blue Moon isn't actually blue. It's "mostly bright white but can take on a bluish hue depending on the season and conditions," the Miami Herald explains. Blue Moons are also special because they're considered to be an "extra" full moon in a season; most seasons have three full moons, while this Blue Moon will be the third of this spring's four full moons. So be sure to check your local weather forecast, grab yourself a cold one, and look up at the night sky this weekend — the next Blue Moon won't happen until January 2018.