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Astronomy Picture of the Day - The Einstein Cross Gravitational Lens
APOD.NASA.gov ^
| 17 Oct, 2021
| Image Credit & License: J. Rhoads (Arizona State U.) et al., WIYN, AURA, NOIRLab, NSF
Posted on 10/17/2021 2:16:06 PM PDT by 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.
TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: astronomy; einsteincross; haltonarp; nasa; physics; quasar; quasars; science; stringtheory
To be added or removed from the Astronomy Picture of the Day ping list please send me a request via "Private Reply" (Mail). 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.
To: MtnClimber
2
posted on
10/17/2021 2:16:24 PM PDT
by
MtnClimber
(For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
To: 21stCenturion; 21twelve; 4everontheRight; abb; AFB-XYZ; America_Right; AZ .44 MAG; BBB333; ...
Pinging the APOD list.
🪐 🌟 🌌 🍔
3
posted on
10/17/2021 2:16:59 PM PDT
by
MtnClimber
(For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
To: MtnClimber
Maybe there's a sale. Or a Broadway opening.
4
posted on
10/17/2021 2:33:26 PM PDT
by
Larry Lucido
(Donate! Don't just post clickbait!)
To: MtnClimber
Dang gravity gets in the way of everything...
At my age, keep telling myself that every time I look into a mirror while shaving...
5
posted on
10/17/2021 2:35:34 PM PDT
by
SuperLuminal
(Where is another Sam Adams now that we desperately need him?)
To: SuperLuminal
Don’t know if anyone else has noticed but gravity has increased as I’ve gotten older.
6
posted on
10/17/2021 2:42:11 PM PDT
by
Hootowl
To: MtnClimber
That’s just what it looked like right before that truck hit me.
Knocked my cheeseburger right out of my hand.
7
posted on
10/17/2021 2:47:18 PM PDT
by
blueunicorn6
("A crack shot and a good dancer”)
To: MtnClimber
Beep-boop-boop-beep-beeeeeeep . . . (tune from Close Encounters of the Third Kind). :-)
8
posted on
10/17/2021 2:47:45 PM PDT
by
AFB-XYZ
(Stand up, or bend over)
To: Hootowl
Don’t know if anyone else has noticed but gravity has increased as I’ve gotten older. Stoppit! Yer killin' me! LOL
9
posted on
10/17/2021 2:48:51 PM PDT
by
AFB-XYZ
(Stand up, or bend over)
To: Larry Lucido
A long long time ago, in a galaxy far, far away…….
10
posted on
10/17/2021 2:52:12 PM PDT
by
telescope115
(Proud member of the ANTIFAuci movement. )
To: 6SJ7; AdmSmith; AFPhys; Arkinsaw; allmost; aristotleman; autumnraine; bajabaja; ...
11
posted on
10/17/2021 8:21:02 PM PDT
by
SunkenCiv
(Imagine an imaginary menagerie manager imagining managing an imaginary menagerie.)
To: SunkenCiv
To: M_Continuum
13
posted on
10/18/2021 8:32:27 AM PDT
by
SunkenCiv
(Imagine an imaginary menagerie manager imagining managing an imaginary menagerie.)
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