Astronomy Picture of the Day · February 20, 2011

Mammatus Clouds Over Olympic Valley

The Astronomy Picture of the Day for February 20, 2011 is “Mammatus Clouds Over Olympic Valley,” an image. It is credited to Credit & License: Matt Saal ( Wikipedia ). The original explanation runs about 121 words.

From the explanation

“What’s happened to these clouds? Normal cloud bottoms are flat because moist warm air that rises and cools will condense into water droplets at a very specific temperature, which usually corresponds to a very specific height.”

— APOD editors, February 20, 2011

Read the full explanation on science.nasa.gov

At a glance

Date: February 20, 2011
Type: Image
Credit: Credit & License: Matt Saal ( Wikipedia )
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 121 words

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On this day: February 20 in other years

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Source

Astronomy Picture of the Day, February 20, 2011 — science.nasa.gov/image-article/apod-2011-february-20-mammatus-clouds-over-olympic-valley

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.