Of course, the Saturday month will not really be blue. And the reason for the name is a bit confusing.
A blue moon is the second of two full months a month – but it can also be third of all four months in a single period. In this case, this is the third of all four months in this spring. These do not happen as much as two whole months in a month.
"The name" Blue Moon "has nothing to do with the color of the Moon," Si Gianluca Masi, astrophysicist and director of the Virtual Telescope Project in Rome, wrote in an email. "Every two to three years we have 13 full Moons for a year, so we can have four whole months at a time or two full months a month."
This is the last seasonal blue moon until August 2021.
Tiny, two types of blue moons occur one year; this will take place in 2048, including a monthly blue moon in January and a seasonal one in August.
Sometimes, the moon may actually appear blue in certain conditions of the sky, but it can not be predicted.