Astronomy Picture of the Day ·

Confirmed Muon Wobble Remains Unexplained

The Astronomy Picture of the Day for April 13, 2021 is “Confirmed Muon Wobble Remains Unexplained,” an image. It is credited to Image Credit: Fermi National Accelerator Laboratory ; Photographer: Reidar Hahn. The original explanation runs about 181 words.

A picture of the center of the Flame Nebula is shown, with the bright star Alnitak off on the left. For more details, please read the explanation.
Credit: Image Credit: Fermi National Accelerator Laboratory ; Photographer: Reidar Hahn Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“How fast do elementary particles wobble? A surprising answer to this seemingly inconsequential question came out of Brookhaven National Laboratory in New York , USA in 2001, and indicated that the Standard Model of Particle Physics , adopted widely in physics, is incomplete.”

— APOD editors, April 13, 2021

Read the full explanation on science.nasa.gov

At a glance

Date
April 13, 2021
Type
Image
Credit
Credit: Image Credit: Fermi National Accelerator Laboratory ; Photographer: Reidar Hahn
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 181 words

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On this day: April 13 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.