VietNamNet Bridge – In the early morning of August 11, two consecutive astronomical events, a full moon and supermoon, will be visible in Vietnam.

A supermoon is the coincidence of a full moon or a new moon with the closest approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth.

The technical name is the perigee-syzygy of the Earth-Moon-Sun system. The term "supermoon" is not astronomical, but originated in modern astrology.

The association of the Moon with both oceanic and crustal tides has led to claims that the supermoon phenomenon may be associated with increased risk of events such as earthquakes and volcanic eruptions, but the evidence of such a link is widely held to be unconvincing.

The most recent occurrence was on July 12, 2014. The next and closest supermoon of 2014 will be on August 11.

When the supermoon occurs, the moon will be 30% lighter and 14% closer to Earth than the usual moon. However, if observed with the naked eye, the difference is difficult to notice.

Mr. Dang Tuan Duy, from the Ho Chi Minh City Amateur Astronomers’ Club (HAAC), said the full moon will occur at 1.09am (Hanoi time). About 20 minutes before, it will be another phenomenon at 0h44, when the Moon reaches the perigee and this is the nearest place in 2014 at a distance of 356.896 km.

According to astronomers, the moon will not come close to the Earth at a distance similar until September 28, 2015.

"This may be considered the closest and brightest full moon of 2014, also known as the closest super moon in 2014," said Duy.

According to Duy, the previous full moons were also called supermoon, but the distance was larger and the time between the perigee and full moon was somewhat longer, not at the same time, compared to August 11.

S. Tung