Lunar eclipse 2021: Where and when to watch longest Chandra Grahan in 580 yrs online

Lunar eclipse 2021: The Chandra Grahan will last for over 3 hrs, which makes it the longest in 580 years.

Lunar eclipse 2021: NASA says that a lunar eclipse occurs when the Sun, the Earth, and the Moon align. (REUTERS)

Lunar eclipse 2021: Skygazers, buckle up! A magnificent treat is in store as a partial lunar eclipse is all set to happen on November 19. This is the second lunar eclipse of the year. The first lunar eclipse took place in May 2021. Notably, this partial lunar eclipse won't be witnessed across the globe on the same day. While people in North America will witness the celestial event on the night of November 18, people in other parts of the world will witness a deep partial lunar eclipse on November 19. Overall, the eclipse will last for a total of three hours twenty-eight minutes and twenty-four seconds, which makes it the longest in 580 years. Chandra Grahan 2021 will be visible in just a couple of states in India.

NASA explains that a lunar eclipse occurs when the Sun, the Earth, and the Moon align so that the Moon passes into Earth's shadow. In a total lunar eclipse, the entire Moon falls within the darkest part of Earth's shadow, called the umbra. In this eclipse, up to 99.1% of the Moon's disk will be within Earth's umbra.

On the other hand, a partial lunar eclipse is an imperfect alignment of the Sun, the Earth and the Moon, which results in the Moon passing through only part of Earth's umbra. In the case of the partial lunar eclipse, the shadow grows and then recedes without ever entirely covering the Moon.

November 19 lunar eclipse date and time: When to watch

NASA has shared the exact course that the Sun, the Earth and the Moon will be charting on the day of the lunar eclipse. If you want to watch the lunar eclipse, here's how the three celestial bodies will move:

-- At 10:02 PM PST on November 18 [11:32 AM IST on November 19] Penumbral eclipse will begin. The Moon will enter the Earth's penumbra, the outer part of the shadow. After that, the Moon will begin to dim, but the effect is expected to be quite subtle.

-- At 11:19 PM PST on November 18 [12:49 PM IST on November 19] Partial eclipse will begin. The Moon will begin to enter Earth's umbra and the partial eclipse begins. To the naked eye, as the Moon moves into the umbra, it looks like a bite is being taken out of the lunar disk. The part of the Moon inside the umbra will appear very dark.

-- 12:45 AM PST [2:45 PM IST on November 19] on November 19 Red colour will become visible. NASA says that more than 95% of the Moon's disk is in the umbra and the Moon will appear red. The colour might be easier to see in binoculars or a telescope. Using a camera on a tripod with exposures of several seconds will bring out the colour, at the expense of overexposing the lit part of the Moon.

-- At 1:03 AM PST on November 19 [2:33 PM IST on November 19] the eclipse will peak. The peak of the eclipse will occur at 9:03 UTC. This is the best time to see the red colour.

-- At 1:20 AM PST on November 19 [2:33 PM IST on November 19] the red colour will no longer be visible. NASA says that the redness fades as less than 95% of the Moon is in the Earth's umbra. It appears that a bite is taken out of the opposite side of the Moon from earlier.

-- At 2:47 AM PST on November 19 [2:50 PM IST on November 19] the partial lunar eclipse will begin. The whole Moon is in Earth's penumbra, but again, the dimming is subtle.

-- At 4:04 AM PST on November 19 [5:34 PM IST on November 19] the Penumbral eclipse will end. The eclipse will end.

Lunar Eclipse 2021: When to watch Chandra Grahan in India

November 19's lunar eclipse will be visible in India at 2.34 PM as 97% of the Moon will be covered by the Earth's shadow. It will be visible from a few areas in Arunachal Pradesh and Assam just after the moonrise.

Lunar Eclipse 2021: How to watch Chandra Grahan in India

People who live in the North-East part of the country can watch the lunar eclipse using their naked eyes. You can also watch the live stream of the eclipse on the YouTube channel of timeanddate.com.