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Astronomy Picture of the Day - Dark Matter in a Simulated Universe
NASA ^ | 20 Oct, 2024 | Illustration Credit & Copyright: Tom Abel & Ralf Kaehler (KIPAC, SLAC), AMNH

Posted on 10/20/2024 1:01:17 PM PDT by MtnClimber

Explanation: Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and why visible matter is distributed as it is both in the local universe and on the cosmic microwave background. The featured image from the American Museum of Natural History's Hayden Planetarium Space Show Dark Universe highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer simulation, complex filaments of dark matter, shown in black, are strewn about the universe like spider webs, while the relatively rare clumps of familiar baryonic matter are colored orange. These simulations are good statistical matches to astronomical observations. In what is perhaps a scarier turn of events, dark matter -- although quite strange and in an unknown form -- is no longer thought to be the strangest source of gravity in the universe. That honor now falls to dark energy, a more uniform source of repulsive gravity that seems to now dominate the expansion of the entire universe.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa
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1 posted on 10/20/2024 1:01:17 PM PDT by MtnClimber
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To: MtnClimber

2 posted on 10/20/2024 1:01:41 PM PDT by MtnClimber (For photos of scenery and wildlife, click on my screen name for my FR home page. More photos added.)
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To: 21stCenturion; 21twelve; 4everontheRight; A Navy Vet; abb; AFB-XYZ; AFPhys; Agatsu77; ...
Pinging the APOD list

🪐 🌟 🌌 🍔

3 posted on 10/20/2024 1:02:30 PM PDT by MtnClimber (For photos of scenery and wildlife, click on my screen name for my FR home page. More photos added.)
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To: MtnClimber

Looks like a bunch of fireflies in a bunch of tree limbs.


4 posted on 10/20/2024 1:05:51 PM PDT by SkyDancer ( ~ Am Yisrael Chai ~)
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To: MtnClimber

Would have been good for a Hallowe’en post...


5 posted on 10/20/2024 1:14:08 PM PDT by Jamestown1630 ("A Republic, if you can keep it.")
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To: MtnClimber

Looks like Hell!


6 posted on 10/20/2024 1:14:39 PM PDT by Harpotoo (Being a socialist is a lot easier than having to WORK like the rest of US:-))
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To: MtnClimber

Why don’t they just call dark matter God? The theory is as close to religion as you can get.


7 posted on 10/20/2024 1:16:54 PM PDT by wildcard_redneck (He who sacrifices freedom for security deserves neither.)
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To: wildcard_redneck
Midori was sitting in the breakfast nook enjoying a coffee while watching a TV science documentary about the Hubble Space Telescope on her Android tablet. Her teenage daughter, Suguha, looked in the frig for some leftovers while trying to ignore the audio.

A man was speaking: "The Hubble Ultra Deep Field image is incredibly important. When NASA aimed the world's most powerful telescope at an empty patch of sky the size of a grain of sand at arm's length, a patch that seemed utterly empty and devoid of any stars or galaxies or anything else, it captured an image of over 10,000 galaxies, each with hundreds of billions of stars. That image should be physically impossible."

A woman, possibly the interviewer, asked, "How do you mean 'impossible'?"

Suguha poked her head deep inside the refrigerator.

Where is that leftover KFC?

"Well, you have to understand the mathematics of it. It has to do with something called the alpha opacity function, a concept familiar to video game designers. In a 3-D video game, every object or texel is assigned an RGBA value: red, green, blue, alpha. The alpha value determines the the opacity of that the object or texel at that point. This determines its transparency: 0.0 is fully transparent, and 1.0 is fully opaque, typically scaled on integral values from 0 to 255. Video games are of course discrete, not continuous, simulations and therefore the RGBA values either quickly saturate - go to 1.0 - or remain at 0.0, nothing in-between.

"You see, achieving partial transparency that doesn't enfog the player is incredibly hard, and many video game designers simply cheat and create a fake fog that kicks in at a fixed distance. Creating a 3-D simulation over unimaginable distances while still revealing interesting objects at those distances is practically impossible."

"So you're saying it is probably not random."

Ah, there is the chicken bucket.

"The opacity gradient has to be inconceivably precise to be able to see such interesting details on literally the far side of the universe. For it to be merely random would be like hitting the Power Ball Jackpot. And you can't hand-wave it away with the Anthropic Principle either."

"So, in your opinion, the fact that we can see all those lovely swirling galaxies is not a coincidence?"

"No, it is not. And they shouldn't be 'swirling' either."

Hey, who ate all the drumsticks?

"How do you mean?"

"The pinwheel structure of a galaxy is mathematically impossible. Spiral galaxies simply shouldn't exist. Computational physicists have tried for decades to create computer simulations that would create a long-term pinwheel structure of a typical spiral galaxy and it just doesn't work, at least not without cheating. It always smears into a blob."

Suguha rolled her eyes while trying to ignore the audio.

Everyone in this house is a geek. Mom, Kazuto, Sachi. Why am I the only normal one?

"Then dark matter (DM) was discovered. Why does dark matter exist? There's no reason for it. It definitely exists - gravitational lensing reveals it everywhere in the cosmos - but there's nothing in the Standard Model that explains it. It's just there. But why? It's only use seems to be for creating interesting and beautiful galactic structures that we can actually see at cosmological distances."

"But why is it like that?"

Suguha sat on a chair at the breakfast nook and ate a cold chicken breast with her fingers.

The man's voice was getting excited. "Exactly! Don't you see what this means? The Hubble Ultra Deep Field is the 'smoking gun', so to speak. The fact that miraculous photo exists, that the Universe seems to be carefully crafted so that we as humans can actually see all these amazing, beautiful, and glorious galaxies by the billions, strongly implies that someone or something..."

Suguha rolled her eyes.

You want to see a miracle?

Suguha picked up another piece of cold chicken as she tried to tune out the annoying video, which Midori continued to watch with keen interest.

The miracle is how my geek mother ever managed to marry a normal guy and make babies.

Suguha dug into the chicken wing.

8 posted on 10/20/2024 1:24:07 PM PDT by Gideon7
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To: Gideon7; Darksheare

A post worthy of Darks!


9 posted on 10/20/2024 1:34:11 PM PDT by null and void (If the government won't protect the vote, the border, the citizens, then why have that government?)
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To: MtnClimber

Interesting.


10 posted on 10/20/2024 1:36:32 PM PDT by No name given ( Anonymous is who you’ll know me as )
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To: null and void; Gideon7

Yes.
Not my fault


11 posted on 10/20/2024 1:47:20 PM PDT by Darksheare (Those who support liberal "Republicans" summarily support every action by same. )
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To: Darksheare

Dark matter? Dark energy?
You disavow them both?
Color me skeptical...


12 posted on 10/20/2024 1:58:35 PM PDT by null and void (If the government won't protect the vote, the border, the citizens, then why have that government?)
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To: null and void

It is not for me to reveal the method of action.


13 posted on 10/20/2024 2:11:32 PM PDT by Darksheare (Those who support liberal "Republicans" summarily support every action by same. )
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To: null and void

More worthless nasa coloring book images


14 posted on 10/20/2024 2:24:43 PM PDT by George from New England (escaped CT back in 2006tt)
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To: MtnClimber

The science is settled but they cannot even explain what dark matter is.

Parallel universes or some such weird stuff?


15 posted on 10/20/2024 2:47:16 PM PDT by doorgunner69 (I don't know what he said at the end of that sentence. i don't think he knows what he said either)
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To: MtnClimber

My take on dark matter is scientists are in the dark about what is going on so they create a mathematical black box to fudge results. The Webb space telescope observations already have scientists scrambling to revisit what they think they know..


16 posted on 10/20/2024 2:56:10 PM PDT by EVO X ( )
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To: MtnClimber

Still running with the dark-matter scam because they can’t admit that they don’t know enough about gravity yet.


17 posted on 10/20/2024 3:09:57 PM PDT by Excuse_My_Bellicosity (Liberalism is a social disease.)
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To: Darksheare

Fair enough.


18 posted on 10/20/2024 3:13:58 PM PDT by null and void (If the government won't protect the vote, the border, the citizens, then why have that government?)
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To: EVO X

There’s several theories about what’s going on there. The scientific community has latched onto dark-matter because the top half-dozen Ph.D.’s in the field have said that is THE theory and you’ll be blackballed if you suggest something else might be going on.


19 posted on 10/20/2024 3:14:22 PM PDT by Excuse_My_Bellicosity (Liberalism is a social disease.)
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To: MtnClimber

Looks like a cluster of neurons, dendrites and axons.


20 posted on 10/20/2024 3:19:14 PM PDT by going hot (Happiness is a Momma deuce)
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