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Only when the moon, Earth and the sun are perfectly aligned is the moon 100% full. And sometimes — once in a blue moon — the moon is full twice in a month (or four times in a season ...

Want to capture tonight's “blue supermoon” with your smartphone? Taking a clear photo of the full moon using just a phone is tough due to the small size of the moon in the sky and your phone's ...

The super blue moon sets behind the Balmoral Clock in Edinburgh. (Photo by Jane Barlow/PA Images via ... [+] Getty Images) At 222,023 miles (357,311 km) from Earth it was the closest full moon ...