By Brandie Jefferson
The rise of Tuesday’s full moon will bring up something special: A Blue Moon.
Before you start turning pages in your favorite astronomy reference book–let’s clear this up. It’s true; the most common usage for Blue Moon (besides referring to that song in that movie with John Travolta) refers to the second full moon in a single month.
And although Tuesday’s full moon will be just the first full moon in August (typically there are two full moons per month), there are several other meanings for the term, according to Space.com.
A less common usage dates back to at least 1937, according to Space.com, in which a Blue Moon is the third of four full moons each season (where a season is the time from the equinox to the solstice, or from the solstice to the equinox).
Tuesday’s Blue Moon, then, is what’s known as a seasonal blue moon: The third this season (that’s summer, if Monday’s fall-like temperatures have you confused).
The rarest Blue Moon is a phenomenon in which the moon actually looks … wait for it … Yes, blue. This is caused by particles in the air—often ash and dust caused by a volcano or a forest fire.
The National Weather Service is forecasting mostly clear skies Tuesday night in Harford County. Why not step outside at about 1:12 a.m. (early Wednesday morning) and look up anyway? No matter what color, a full moon is always a magnificent sight.