Astronomy Picture of the Day · December 15, 2011

The Umbra of Earth

The Astronomy Picture of the Day for December 15, 2011 is “The Umbra of Earth,” an image. The picture is copyrighted by its creator (Image Credit & Copyright: Wang, Letian). The original explanation runs about 138 words.

From the 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 .”

— APOD editors, December 15, 2011

Read the full explanation on science.nasa.gov

At a glance

Date: December 15, 2011
Type: Image
Credit: Credit: Image Credit & Copyright: Wang, Letian
Copyright: Copyrighted by the credited creator. Ask the copyright holder before reusing it.
Explanation length: About 138 words

All of December 2011 → · 2011 by month → · Full archive since 1995 →

Topics in this entry

The Moon Eclipses

Topics are matched from words in the title and explanation.

On this day: December 15 in other years

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Source

Astronomy Picture of the Day, December 15, 2011 — science.nasa.gov/image-article/apod-2011-december-15-the-umbra-of-earth

Copy taken Oct 28, 2026, 2:39 AM EDT. The image and explanation belong to their creators. OpenOrbit is not affiliated with or endorsed by NASA.