Astronomy Picture of the Day - The Einstein Cross Gravitational Lens

NASA ^ | 4 Jan, 2026 | Image Credit & License: NSF, NOIRLab, AURA, WIYN; Processing: J. Rhoads (Arizona State U.) et al.

[MtnClimber]

Explanation: Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image. The central cloverleaf is rather light emitted from a background quasar. The gravitational field of the visible foreground galaxy breaks light from this distant quasar into four distinct images. The quasar must be properly aligned behind the center of a massive galaxy for a mirage like this to be evident. The general effect is known as gravitational lensing, and this specific case is known as the Einstein Cross. Stranger still, the images of the Einstein Cross vary in relative brightness, enhanced occasionally by the additional gravitational microlensing effect of specific stars in the foreground galaxy.

[MtnClimber]

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For more detail go to the link and click on the image for a high definition image. You can then move the magnifying glass cursor then click to zoom in and click again to zoom out. When zoomed in you can scan by moving the side bars on the bottom and right side of the image.

[MtnClimber]

[MtnClimber]

Pinging the APOD list

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[coloradan]

Pictures or it didn’t happen

[telescope115]

For some reason APOD won’t load….

[MtnClimber]

It is loading for me. That is unusual.

[MikelTackNailer]

I couldn't get it to load yesterday, either.
It's clearly the Space Communists

retaliating for Venezuela.

[Diogenesis]