For those who have not yet observed any of the supermoons this year, the third and final event of the trilogy of supermoons this summer will occur on Monday, September 8.
The moon will be in its full phase at 9:38 p.m. EDT on Monday but it will be nearest the Earth 22 hours earlier so the moon will appear biggest on Sunday at 11:38 p.m. EDT when it is just 222,698 miles away from the Earth. Astronomers, however, said that only observant lunar spectators would notice that the moon will appear 7 percent bigger and 15 percent brighter than the ordinary full moon.
The National Aeronautics and Space Administration (NASA) said that it is not easy to distinguish the difference between an ordinary full moon and a supermoon citing that a 30 percent difference in the lunar orb's brightness could be masked by clouds and haze.
"Also, there are no rulers floating in the sky to measure lunar diameters," the U.S. space agency wrote on its website. "Hanging high overhead with no reference points to provide a sense of scale, one full Moon looks about the same size as any other."
The full moon on Monday is the nearest to this year's September equinox and is thus known as the Harvest Moon. Although the Harvest Moon is often associated with Autumn, the lunar event on Monday marks the last full moon of the summer season.
As for the best time to catch the finale of the series of summer supermoons that began on July, Geza Gyuk, an astronomer from the Adler Planetarium in Chicago said that as long as the weather permits, a full moon is visible all night and the exact time of perigee and fullness do not really matter so much. Gyuk recommended choosing a convenient time that would allow a few minutes to appreciate and observe the lunar event.
"Try and look for the moon when it is near the horizon, that's when it gives an extra thrill, as it appears larger and more colorful than when it is overhead," Gyuk said.
Gyuk also said that photo enthusiasts could capture the best shots as the moon rises above the horizon and sets at sunrise as it is perched above foreground objects such as trees and bodies of water.
"Slightly after sunset, when the moon is low in the sky and the sky is darkening, is very dramatic for viewing and photography," Gyuk said.