What a celestial year for the country.
On Saturday, July 28, people across Vietnam will have the chance to witness the longest total lunar eclipse in the 21st century — which will last for 103 minutes, VnExpress reports. The phenomenon will also be visible in most parts of Australia, Africa, Europe, Asia and South America.
A total lunar eclipse is a condition when the Earth's shadow blocks out the light rays of the sun directly reflecting on the moon, which results in a dull red moon because the sunlight that the moon receives has been refracted by the atmosphere of the Earth.
How long each time the phenomenon happens is influenced by the relative distances between the Earth, the moon and the sun. On July 27, the Moon reaches apogee — the farthest point from Earth — which causes a decrease in orbital speed, lengthening the duration of the total lunar eclipse. July is also a month when the Earth is near its farthest point from the sun, which causes the planet to cast a bigger shadow, which takes the moon a longer time to finish passing through it.
By 12:14am (local time) on Saturday, the moon will start entering the Earth's penumbra. The total eclipse will start at 2:30am when the moon enters Earth's umbra — the darkest part of Earth's shadow — and start turning red. By 3:21am, the moon will reach the center of the Earth's umbra and by 4:13am, the total eclipse will end. The moon will then go phase through a partial eclipse and penumbra eclipse until the phenomenon officially ends at 6:28am the same day.
Unlike a solar eclipse, the lunar eclipse is completely safe to watch with bare eyes. Binoculars, telescopes or cameras with decent zoom lenses would help make the viewing experience more worthwhile. Weather will be the deciding factor on whether Vietnamese can enjoy the phenomenon or not. If it rains or the sky is cloudy, chances are the moon will be hidden from view.
According to the Director of Vietnam's Astrology and Cosmology Association (VACA) Dang Vu Tuan Son, watching the eclipse might get tricky in bad weather: "If there are few clouds in the sky, some parts of the moon will be hidden. However, if you have patience, the moon will come out eventually. If the sky is too foggy, you should cancel your stargazing session or temporarily postpone it with the hope that the clouds will clear soon. If possible, choose a location with less pollution and light, so that the moon can appear clearer."
If one is curious enough to either stay up late or wake up early for the spectacle, it's worth keeping an eye out for Earth's dusty neighbor Mars as well. During July and August, Mars will be at its brightest on Earth's sky ever since 2003.
[Photo: The super-moon full lunar eclipse on September 27, 2015. (via Imgur user SeanKorbitz)]
