Photographer's Note

The December 21 Lunar Eclipse was a spectacular event seen across North America. With 73 minutes of totality, viewers with clear weather were treated to a blood red moon - red due to the Rayleigh scattering from the Earth's atmosphere reflecting the shorter wavelengths away.

Lunar eclipses are rare - since although the moon is full each month, it rarely passes directly into the Earth's umbra. In fact, the last one was almost 3 years ago - the subject of the third photo uploaded here on TE.

Of course, you might wonder what a photograph of the moon is doing on a site called TrekEarth. Which is a valid question - especially since TrekMoon doesn't exist - atleast not yet. However, what you're looking at is indeed the Earth, or rather, it's shadow on the moon. In reality, the moon covers a much larger angular distance across the sky; however, I have arranged the phases so that the umbra of the Earth's shadow is stationary.

If it is difficult to see the shadow of the Earth here, take a look at the workshop I've posted. It's amazing to think that somewhere in that edge of the Earth is a really blurred shadow of the Eiffel tower.

After taking the ratio of the diameters of the terrestrial umbra and the orb of the moon I found, after a bit of calculation, that the current earth-moon distance was about 386000 km. That is at least in the right range (it varies between 405000 and 363000 km).

worldcitizen, CLODO, magalik, ahtiwana, Angshu, bona, happypoppeye trouve(nt) cette note utile

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Additional Photos by Biswaroop Mukherjee (bmukherjee) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 218 W: 72 N: 211] (1516)
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