Astronomy Picture of the Day -- The Umbra of Earth

NASA ^ | December 15, 2011 | (see photo credit)

[SunkenCiv]

Explanation: The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section most easily seen during a lunar eclipse. For example, last Saturday the Full Moon slid across the southern half of Earth's umbral shadow, entertaining moonwatchers around much of the planet. In the total phase of the eclipse, the Moon was completely within the umbra for 51 minutes. Recorded from Beijing, China, this composite eclipse image uses successive pictures from totality (center) and partial phases to trace out a large part of the umbra's curved edge. Background stars are visible in the darker eclipse phases. The result shows the relative size of the shadow's cross section at the distance of the Moon, as well as the Moon's path through Earth's umbra.

[SunkenCiv]

[Credit & Copyright: Wang, Letian]

[SunkenCiv]

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[Jonty30]

Thanks Sunkenciv.

It’s a great pic.

[Graewoulf]

BUMP!

[PA Engineer]

You are a Freeper treasure. Thanks for the post. BTTT.

[unkus]

Awesome, as usual. Thank you, SunkenCiv.

[.30Carbine]

FAS. CIN. NATE. ING!

[ixtl]

Think of all the conditions required to make an eclipse possible. The distance from the sunto the earth/mooon system. The distance between the earth and the moon. The size of the earth. The size of the moon. Nowhere else in the solar system will you find this same combination.

Thanks for the picture.

[brytlea]

BEautiful!

[dfwright]

That is very cool!

[TheOldLady]

Oooooh! That is a perfect picture. The shadow of the earth on the moon showing the relative size of the two bodies. Ahhh! Spectacular! I don’t save many of these APODs, but this one is a keeper.