There are several versions this (completely untrue) story, and we’ve gotten many questions about it from within our community, from people wanting to know if it’s true. Here’s the main version: the moon will appear green for the first time in 420 years on April 20, 2016. True? No, not even kinda. Snopes called it:
… entirely humorous in nature.
And it is pretty funny when you think about April 20 (4-20) and 420 years, and realize that 420 is a code word for marijuana (invented, according to Urban Dictionary, by “dozen pot-smoking wiseacres” at San Rafael High School in 1971) and that the date April 20 has special meaning to some as Weed Day.
All of that notwithstanding, many appear to be taking the April 20, 2016, green moon literally.
And we repeat … it’s not true.
— Freia L.S (@lovelornbelle) April 4, 2016
Snopes explained said that the meme began as a photograph on Facebook claiming that on May 29, 2016, the moon would appear green in the sky:
The Facebook user added the following completely erroneous piece of information in explanation of his post. Why erroneous? Uranus is nowhere near the moon on this night; in fact, it’s about half a sky away.
For those who need information on how this works … All night long on Sunday, May 29th the seventh planet from the sun, Uranus, will park itself near the moon. The green giant is only 4 degrees away from the moon. The cosmic odd-couple will appear about four degrees apart in the sky—equal to 8 full moons side-by-side. This week after darkness falls the near full moon acts as a convenient guidepost for finding Uranus.
He has since taken his post down and photo down.
Bottom line: No, there won’t be a green moon on April 20, 2016 … or on May 29.
Deborah Byrd created the EarthSky radio series in 1991 and EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.