PH to experience 2021's longest day on June 21

The summer solstice will mark the year's longest day and shortest night on Monday, June 21.

During this astronomical event, the sun attains its greatest declination of +23.5 degrees and passes directly overhead at noon for all observers at latitude 23.5 degrees North, which is known as the Tropic of Cancer, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) explained.

"This event marks the start of the apparent southward movement of the Sun in the ecliptic," it added.

PAGASA said that the Philippine nighttime will be at its shortest and daytime at its longest during the summer solstice, which falls on June 21 at 11:32 a.m. (Philippine Standard Time).

On Monday, the country's daytime will last for 12 hours and 59 minutes as the sun will rise at 5:28 a.m. and will set at 6:27 p.m.

The summer solstice is the day of the year with the longest daylight period and hence the shortest night, which usually occurs on June 21 or June 22 in the northern hemisphere. It falls on June 21 this year.

For some countries, particularly those that have four seasons in a year, the solstice marks the start of summer in the northern hemisphere and winter in the southern hemisphere.