Astronomy Picture of the Day ·

The Same Color Illusion

The Astronomy Picture of the Day for December 18, 2023 is “The Same Color Illusion,” an image. It is credited to Image Credit: Edward H. Adelson , Wikipedia. The original explanation runs about 125 words.

A checkerboard is shown with squares colored light and dark grey. A green tube sits on the board and casts a shadow. The image has a letter A typed on a dark square, and a letter B types on a light square cast in shadow. The question is ask
Credit: Image Credit: Edward H. Adelson , Wikipedia Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“Are squares A and B the same color? They are!”

— APOD editors, December 18, 2023

Read the full explanation on science.nasa.gov

At a glance

Date
December 18, 2023
Type
Image
Credit
Credit: Image Credit: Edward H. Adelson , Wikipedia
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 125 words

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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.