The nearly full-moon is seen among Christmas lights at a holiday display Thursday, Dec. 24, 2015, in Lenexa, Kan. When the moon turns full, at 5:11am cst., it will be the first full moon to fall on Christmas day since 1977. Named the Long Night Moon because it's the first full moon to follow the winter solstice, it's also known as the Cold Moon. (AP Photo/Charlie Riedel)
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PHILADELPHIA (AP) - Gaze up into the sky and you'll see something rare. And, no, it won't be Santa. He and his reindeers will have already zoomed across the horizon.
On Christmas Day, there will be a full moon, the first since 1977. It will reach its peak at 6:11 a.m. EST.
This full moon, the last one for 2015, is called a Full Cold Moon because it happens during the start of winter. Of course "cold" is relative these days. On the balmy U.S. East Coast, some people will be tempted to celebrate the holiday in shorts and flip flops, more like Hawaiians.
NASA has a spacecraft currently orbiting the Earth's moon. Its Lunar Reconnaissance Orbiter mission has been investigating the moon's surface since 2009. The space agency says the mission has collected a "treasure trove of data" and is "making an invaluable contribution to our knowledge about the moon."
A full moon on Christmas won't happen again until 2034, nearly two decades from now, NASA said. So, unless you have a very good memory, you might want to look up at the sky on Friday and marvel at the moon's magnificence.
The nearly-full moon is seen among Christmas lights at a holiday display Thursday, Dec. 24, 2015, in Lenexa, Kan. When the moon turns full, at 5:11am cst., it will be the first full moon to fall on Christmas day since 1977. Named the Long Night Moon because it's the first full moon to follow the winter solstice, it's also known as the Cold Moon. (AP Photo/Charlie Riedel)
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An airplane crosses a nearly full-moon on its way to Los Angeles International Airport near Whittier, Calif., Thursday, Dec. 24, 2015. Not since 1977 has a full moon dawned in the skies on Christmas. (AP Photo/Nick Ut)
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The Long Night Moon rises behind a cross at Christ Community Church in Lawrence, Kan., Thursday, Dec. 24, 2015. When the moon turns full, at 5:11am cst., it will be the first full moon to fall on Christmas day since 1977. Named the Long Night Moon because it's the first full moon to follow the winter solstice, it's also known as the Cold Moon. (AP Photo/Orlin Wagner)
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A full moon rises over the traditional Norwegian Christmas tree in London's Trafalgar Square, Thursday, Dec. 24, 2015. Not since 1977 has a full moon dawned in the skies on Christmas, but 2015 sees a bright full moon as an added gift for the holidays. Decemberâs full moon, the last of the year, is called the Full Cold Moon because it occurs during the beginning of winter. (AP Photo/Alastair Grant)
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A full moon rises next to a digital stock market feed in London's Trafalgar Square, Thursday, Dec. 24, 2015. Not since 1977 has a full moon shone in the skies on Christmas, but 2015 sees a bright full moon as an added gift for the holidays. Decemberâs full moon, the last of the year, is called the Full Cold Moon because it occurs during the beginning of winter. (AP Photo/Alastair Grant)
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A full moon seen through decorations in Oktyabrskaya Square, decorated to mark the upcoming Christmas and New Year celebrations in Minsk, Belarus, Thursday, Dec. 24, 2015. (AP Photo/Sergei Grits)
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The Full Cold Moon seen through the star of a Christmas tree in Beirut, Lebanon, Thursday, Dec. 24, 2015. The full moon, which is the last of the year, is called the Full Cold Moon because it occurs at the start of winter. The last time there was a full moon on 25 December was 1977, and there won't be another one until 2034. (AP Photo/Hassan Ammar)
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