06 June 2011

Total Lunar Eclipse June 15th 2011

It's been a while since the last total lunar eclipse we witnessed in this part of the world. Way back in 2008 August 17th morning at around 2am we had partial eclipse. The last total lunar eclipse we had the opportunity to observe was in 2007 March. This year we have two total lunar eclipses coming up. First one is on June 15th and the second is on December 10th 2011.

June 15th Lunar eclipse details:

The penumbral eclipse begins at 10:54pm IST, this is hard to detect as the difference in the brightness of the Moon is very less. The umbral eclipse will start at 11:52 IST and we will start to see the moon entering the shadow. The moon will be in total eclipse from 12:52am IST to 02:32am IST. The moon will start coming out the umbral shadow after 02:32am and will be completely out of the umbral shadow cone at 3:32am IST. This will mark the end of noticeable change in the moon's brightness and color, the moon will emerge from the penumbral shadow at 4:30am IST.

Altitude of Moon during Eclipse:

Moon will be at an altitude of 56 degrees above the horizon at the beginning of the penumbral eclipse, well placed above trees and buildings if we are observing from city. Maximum eclipse is when the Moon is at the center of the umbral shadow, this happens at approximately 1:42am IST the moon's altitude will be 46degrees from the horizon. At the time when the Moon completely comes out of the umbral shadow the altitude will be 31 degrees.

Color of Moon during Total Lunar eclipse:

Due to the atmospheric refraction moon may appear dark brown and red to bright orange and yellow depending on the amount and type of dust present in the atmosphere.

French astronomer AndrĂ©-Louis Danjon (6 April 1890 – 21 April 1967) developed a scale depending on the brightness and color of the moon during total eclipse.

L=0 Very dark eclipse, Moon is almost invisible, especially at mid-totality.

L=1 Dark eclipse, gray or brownish in coloration, Details are distinguishable only with difficulty.

L=2 Deep red or rust-colored eclipse, Very dark central shadow, while outer umbra is relatively bright.

L=3 Brick-red eclipse, Umbral shadow usually has a bright or yellow rim.

L=4 Very bright copper-red or orange eclipse umbral shadow has a bluish, very bright rim.

The readings can be taken from observing through naked eye, binoculars and small telescopes. Hope we all get chance to observe, enjoy and photograph the event.

Total Lunar Eclipse on December 10th 2011:

The Umbral eclipse begins at 6:15pm on the 12th of December 2011. Moon will be at an altitude of 18degrees from the eastern horizon. Total eclipse will begin at 7:37pm IST and will be in totality till 8:26pm IST. The moon will be at an altitude of 41degrees from the eastern horizon during maximum eclipse which will occur at 8:00pm IST. Moon will emerge completely out of umbral shadow at 9:48pm IST.

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