[File photo]

According to astronomers, another “super moon” will hang in the sky on the evening of Dec. 13. The previous two were visible on Oct. 17 and Nov. 14.

A super moon occurs when a full moon or new moon debuts at the same time as the moon's closest approach to Earth in its elliptical orbit, resulting in the largest and roundest appearance of the moon when viewed from Earth.

Shi Zhicheng, a member of the Chinese Astronomy Society and director of Tianjin Astronomy Society, explained that this coincidence is referred to as perigee, and the opposite pairing is called apogee. The moon's distance varies each month because of its elliptical orbit around Earth.

“The moon was not far from perigee when the three full moons appeared this year. Thus, it is not possible for the general public to tell which is the largest or roundest after the moon rises,” Shi stressed.

Astronomy experts pointed out that super moons are neither mysterious nor strange. Though it is relatively rare for super moons to appear in three consecutive months, it is within the realm of normal.