December 'supermoon' expected to be biggest, brightest of 2017

Nov. 28 (UPI) -- The "supermoon" set for next week is expected to be the brightest of the year as the moon's orbit will be at its closest point to the earth.

Astronomer Marek Kukula at the Royal Observatory Greenwich, Britain, told AGN News a supermoon is when "a full moon happens to occur when the moon is also at its closest point" to the earth and appears brighter and bigger than usual.

It all begins with the December full moon, which will officially occur at 10:47 a.m. EST Sunday, according to National Geographic. Later that night, the "supermoon" will be out and appear 7 percent larger and 16 percent brighter than usual because the lunar orb will be at its closest point to earth in its cycle, coming within 222,443 miles of earth by 4 a.m. EST Monday.

"It is a natural part of the moon cycle and happens around once a year," Kukula said. "The differences in apparent size and brightness amount to few percent but they can enhance the already beautiful sight of the full moon, making a supermoon worth looking up for."

December's supermoon will be the fourth of 2017.