BellaOnline Forums Education Astronomy There's a "blue moon" on Friday

You may see in the media that there's a blue Moon on Friday. In one sense of the expression "blue Moon" that's true. Though you should be warned that the Moon won't actually be blue (unless you have a forest fire nearby). You've probably heard the expression "once in a blue moon". Are "blue Moons" really rare?

Find out more in Once in a Blue Moon.

Volcanic dust and forest fires can make the Moon or Sun appear blue. More rarely, it's possible for water droplets in the atmosphere to give a blue Moon, if they're just the right size. Here's a blue Moon in Texas in 2003.

A 4-minute NASA video gives you an overview of blue moons. Lots of illustrations, and at the end it even explains why you're more likely to see a red "blue moon" than a blue "blue moon".

SpaceWeather.com suggests that if you go out to look at tonight's full Moon that you keep an eye out for meteors. The Southern Delta Aquarid meteor shower is on now, may be producing 10-20 meteors per hour. Two nights ago NASA's all-sky meteor camera network detected a Southern Delta Aquarid fireball over North Caroline.

David Yu, San Francisco photographer, got a splendid picture of last night's blue Moon. But not in San Francisco. He caught it just above the California state capitol building in Sacramento.

Low in the sky, the Moon is a vivid reddish orange. I've never seen the Moon looking blue - and certainly not a blue "blue Moon". But I've often seen a Moon low in the sky looking red, orange or red orange, whether or not it was a "blue Moon".

To complement the orange blue Moon over California's capitol by David Yu, complements of NASA/Bill Ingalls, here is the orange blue Moon over the Capitol Building in the USA's capital.