That definition is, itself, a misinterpretation from the 1940's, popularized in the 1980's, and debunked more recently once the sources were finally tracked down. But the new definition has stuck and won't be going away.
Still, it's interesting. All the more so to me... I was born under a blue moon. Yes, I feel a particular affinity for the Soprano's theme song.
The moon won't actually look "blue" (unless we have another Krakatoa between now and then), but for a red moon, here's one that I took of the full lunar eclipse on February 20, 2008. The bright object in the bottom left is Saturn.
I shot the image standing in the middle of 3rd street in Covington with a normal lens, exposing for 5 seconds, which is why Saturn has the smeary star-trail. For even more info you don't need, the blueish tinge around Saturn is a common problem for astrophotography... "fast" lenses curve the light enough on very bright objects that they get a halo of violet where the UV is pulled into the visual spectrum. I've got a v-fringe filter that mostly eliminates it in my telescopes, but I wanted a wide enough field to include Saturn, so for this shot I just used a normal camera on a tripod.
|From Covington Blog 2009|