Astronomy Picture of the Day ·

Flowing Barchan Sand Dunes on Mars

The Astronomy Picture of the Day for April 20, 2009 is “Flowing Barchan Sand Dunes on Mars,” an image. It is credited to Credit: HiRISE , MRO , LPL (U. Arizona) , NASA. The original explanation runs about 159 words.

Flowing Barchan Sand Dunes on Mars
Credit: HiRISE , MRO , LPL (U. Arizona) , NASA Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“When does Mars act like a liquid? Although liquids freeze and evaporate quickly into the thin atmosphere of Mars, persistent winds may make large sand dunes appear to flow and even drip like a liquid.”

— APOD editors, April 20, 2009

Read the full explanation on science.nasa.gov

At a glance

Date
April 20, 2009
Type
Image
Credit
Credit: HiRISE , MRO , LPL (U. Arizona) , NASA
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 159 words

All of April 2009 → · 2009 by month → · Full archive since 1995 →

Topics in this entry

Mars

Topics are matched from words in the title and explanation.

On this day: April 20 in other years

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Source

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.