MANILA, Philippines (Updated July 25, 2018) — The year 2018 is yet again set to experience another rare astronomical marvel as the world will witness the longest lunar eclipse of the 21st century as July’s blood moon is set to pass by the Earth’s shadow on the night of the 27th to 28th.
According to experts, the total lunar eclipse will last around one hour and 43 minutes, 27 minutes longer than January 31’s Super Blue Blood Moon, which lasted one hour and 16 minutes.
The Philippines, along with the rest of Asia and Australia, will be able to view the blood moon between midnight and sunrise of July 28.
In Philippine time, PAGASA predicts that the lunar eclipse will start with the penumbral eclipse at 1:14 a.m. and the whole eclipse will last until 7:28 a.m., making the totality of the eclipse around 6 hours and 14 minutes.
Weather and astronomy website timeanddate.com presents the same data, showing that after the penumbral eclipse, the country will see the partial eclipse at 2:24 a.m., while the total lunar eclipse will begin at 3:30 a.m.
The maximum eclipse will be at 4:21 a.m. and will end at 5:13 a.m.
PAGASA weather specialist Salvador Quirimit said that starting 5:44 a.m., the country will not be able to view the remaining phases of the eclipse as the moon will set at that time.
Quirimit said the best time to view the eclipse was during the start until 5:13 a.m. and added that the country should look westward to have the best view.
From the perspective of the Philippines, Quirimit said the moon will be setting during the eclipse, which is why the west is the best direction for viewing it.
Why the July eclipse is the longest... plus a blood moon
The July full moon and the July lunar apogee, the moon’s farthest distance from the Earth, both falls on the 27th, making this blood moon appear really small and take more time to pass through the Earth’s shadow.
The blood moon is also set to pass directly through the center of the Earth’s shadow, which makes the duration of the lunar eclipse even longer. The shorter January 31 eclipse only passed through the southern part of the shadow.
A blood moon, sometimes called a “full buck moon,” is called what it is because of the red hue the Sun’s indirect light gives as it bends around the Earth’s atmosphere.
This effect, called “Rayleigh Scattering,” allows the moon to still be seen rather than disappearing completely when blocked by the Earth’s shadow.
The said effect also filters out green and violet light, giving the blood moon its deep orange and red color. — Philstar.com intern Ali Ian Marcelino Biong