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Astronomy Picture of the Day - The Observable Universe
NASA ^ | 23 Nov, 2025 | Illustration Credit & Licence: Wikipedia, Pablo Carlos Budassi

Posted on 11/23/2025 1:06:41 PM PST by MtnClimber

Explanation: How far can you see? Everything you can see, and everything you could possibly see, right now, assuming your eyes could detect all types of radiations around you -- is the observable universe. In light, the farthest we can see comes from the cosmic microwave background, a time 13.8 billion years ago when the universe was opaque like thick fog. Some neutrinos and gravitational waves that surround us come from even farther out, but humanity does not yet have the technology to detect them. The featured image illustrates the observable universe on an increasingly compact scale, with the Earth and Sun at the center surrounded by our Solar System, nearby stars, nearby galaxies, distant galaxies, filaments of early matter, and the cosmic microwave background. Cosmologists typically assume that our observable universe is just the nearby part of a greater entity known as "the universe" where the same physics applies. However, there are several lines of popular but speculative reasoning that assert that even our universe is part of a greater multiverse where either different physical constants occur, different physical laws apply, higher dimensions operate, or slightly different-by-chance versions of our standard universe exist.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa
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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.

1 posted on 11/23/2025 1:06:41 PM PST by MtnClimber
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To: MtnClimber

2 posted on 11/23/2025 1:06:58 PM PST by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: 21stCenturion; 21twelve; 4everontheRight; A Navy Vet; A_perfect_lady; abb; AFB-XYZ; AFPhys; ...
Pinging the APOD list

πŸͺ 🌟 🌌 πŸ”

3 posted on 11/23/2025 1:07:57 PM PST by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber
thank you!!


4 posted on 11/23/2025 1:21:54 PM PST by Diogenesis (Si vis pacem, para bellum)
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To: Diogenesis

It’s not just the Earth that is flat.
The entire Universe is flat!


5 posted on 11/23/2025 1:43:59 PM PST by sjmjax
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To: MtnClimber

Looks like we are in a big, ole sink hole...


6 posted on 11/23/2025 2:27:54 PM PST by goodnesswins (Make educ institutions return to the Mission...reading, writing, math...not Opinions & propaganda)
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