晴時多雲

《TAIPEI TIMES》 ‘Real’ full moon shines on festival night

The moon sets behind the Kaohsiung Lighthouse in Cijin District on the Mid-Autumn Festival yesterday morning.
Photo: Chang Chung-yi, Taipei Times

The moon sets behind the Kaohsiung Lighthouse in Cijin District on the Mid-Autumn Festival yesterday morning. Photo: Chang Chung-yi, Taipei Times

2021/09/22 03:00

‘TECHNICALITY’: The full moon was at 7:55am, but the Taipei Astronomical Museum said it technically remained a ‘real’ full moon when it rose again at night

/ Staff writer, with CNA

The Mid-Autumn Festival had a “real” full moon, the first time the astronomical categorization has fallen on the day of the festival since 2013, the Taipei Astronomical Museum said yesterday.

The festival, which falls on the 15th day of the eighth month of the lunar calendar — which this year was yesterday — does not always coincide with an exact full moon, the museum said.

A full moon occurs when the Earth is between the sun and the moon — or, more precisely, when the ecliptic longitudes of the sun and the moon differ by 180° — which has a cycle of about 29.53 days, it said.

Therefore, a “real” full moon can take place from the 14th to the 17th of a lunar month, with 16th being the most likely, the museum said.

The last time a Mid-Autumn Festival coincided with a real full moon was in 2013, the museum said.

This year, the exact time of the full moon was at 7:55am yesterday, but the museum said it technically remained a “real” full moon when it became visible again at 6:18pm.

新聞來源:TAIPEI TIMES