Blue moons are rare, hence the expression "once in a blue moon," with it only occurring every 2.5 years, according to NASA.

A rare Blue Moon will light up the night skies at the end of May. Sarah Keith-Lucas explains what a Blue Moon is and looks at ...

You’ll be able to get a glimpse in the southwest sky just before dawn on Sunday; here’s more on how blue moons came to be.

We commonly know a blue moon as the second full moon, but this was a mistake from the original meaning and caught on.

NEW ORLEANS (WGNO) – November’s full moon is called the Beaver Moon rising to peak illumination at 8:19 a.m. EDT (so that’s 7:19 a.m. for us) on Wednesday, Nov. 5. Yes, that is when the moon is “below ...

How does a lunar halo form? Halos are often the result of ice crystals in cirrus clouds. When moon or sunlight shines through these crystals, the light refracts or bends. In this case, it does so at ...