The largest full moon of the year — a “supermoon” — falls on the same night as an annual meteor shower hits its peak.
But don't expect a double show. The moon will be so big and so bright that NASA says there's only a slight chance the Eta Aquarid meteor shower will be visible.
David Kriegler of the University of Nebraska at Omaha's physics department said “a full moon by itself will drown out the Eta Aquarid. And the brighter supermoon will make (viewing) even less favorable.''
A supermoon occurs when the moon hits its full phase while also making its closest approach to Earth for the month, called a perigee.
Saturday, the moon will be within 221,802 miles of Earth — its closest approach of the year. It could appear 14 percent bigger and 30 percent brighter than other full moons.
The best time to view it should be the early evening, just after the moon rises. Forecasters, however, are calling for cloudy skies and a 60 percent chance of rain Saturday night in the Omaha metropolitan area.
The most recent supermoon, in March 2011, was the biggest and brightest full moon in 18 years.
Kriegler said there have been about 12 supermoons since 1954, or about one every five years.
The Eta Aquarid display is one of two meteor showers created by dust from Halley's Comet. Eta Aquarid occurs every April and May when Earth passes through debris cast off by Halley in its 76-year trip around the sun.
Kriegler compared the meteor shower with a character in the Peanuts comic strip.
“Comets are like Pigpen,” he said. “They leave behind in their orbit stuff that comes off them, which means we travel through this left-behind debris. Actually, we go through it twice — again Oct. 20 to 21 each year.''
The Eta Aquarid meteor shower began April 19 and will end May 28, with its peak Saturday night.