APOD: Milky Way over a Turquoise Wonderland (2023 May 29)

[APOD Robot]

Milky Way over a Turquoise Wonderland

Explanation: What glows there? The answer depends: sea or sky? In the sea, the unusual blue glow is bioluminescence. Specifically, the glimmer arises from Noctiluca scintillans, single-celled plankton stimulated by the lapping waves. The plankton use their glow to startle and illuminate predators. This mid-February display on an island in the Maldives was so intense that the astrophotographer described it as a turquoise wonderland. In the sky, by contrast, are the more familiar glows of stars and nebulas. The white band rising from the artificially-illuminated green plants is created by billions of stars in the central disk of our Milky Way Galaxy. Also visible in the sky is the star cluster Omega Centauri, toward the left, and the famous Southern Cross asterism in the center. Red-glowing nebulas include the bright Carina Nebula, just right of center, and the expansive Gum Nebula on the upper right.

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[Ann]

Milky Way over a Turquoise Wonderland. Image Credit & Copyright: Petr Horálek / Institute of Physics in Opava, Sovena Jani

---

Milky Way over Bioluminscent Border. Pay attention, people, because this is a sight that you will not find anywhere else in the Universe. Well, the Milky Way will look very much the same from any nearby exoplanet - hey, Proxima Centauri b and d - But the Bioluminescent Border? Forget it.

Unless, of course, Swedish-American physicist Max Tegmark is right that the Universe is "so infinite" that it is bound to repeat itself, and that there is, therefore, a perfect copy not only of the Solar System and the Earth and the bioluminescence but also of every one of us. If so, the likely distance to this perfect copy of you, me and bioluminescence would be 10 to the power of 10 to the power of 28 meters:

Illustration: Alfred T. Kamajian

Max Tegmark of Massachusetts Institute of Technology wrote:

Is there a copy of you reading this article? A person who is not you but who lives on a planet called Earth, with misty mountains, fertile fields and sprawling cities, in a solar system with eight other planets? The life of this person has been identical to yours in every respect. But perhaps he or she now decides to put down this article without finishing it, while you read on.

The idea of such an alter ego seems strange and implausible, but it looks as if we will just have to live with it, because it is supported by astronomical observations. The simplest and most popular cosmological model today predicts that you have a twin in a galaxy about 10 to the 10²⁸ meters from here. This distance is so large that it is beyond astronomical, but that does not make your doppelgänger any less real. The estimate is derived from elementary probability and does not even assume speculative modern physics, merely that space is infinite (or at least sufficiently large) in size and almost uniformly filled with matter, as observations indicate. In infinite space, even the most unlikely events must take place somewhere. There are infinitely many other inhabited planets, including not just one but infinitely many that have people with the same appearance, name and memories as you, who play out every possible permutation of your life choices.

Well, that's a nifty idea, Max. I'm not so sure I believe you.

So let's enjoy the bioluminiscence here on Earth, when and if we can!

Ann

[Chris Peterson]

Milky Way over Bioluminscent Border. Pay attention, people, because this is a sight that you will not find anywhere else in the Universe. Well, the Milky Way will look very much the same from any nearby exoplanet - hey, Proxima Centauri b and d - But the Bioluminescent Border? Forget it.

Oh, I expect that bioluminescent lifeforms are common enough in the Universe, even all over our own galaxy. That's a very simple form of life, which I can easily believe is common. This exact scene? Unique. The bigger picture? Maybe not so much.

[zendae]

This photo reminds me of when I snuck up to the very tippy top of a cruise liner one very late clear night. No land, but the sky and the sea were similar. I was transfixed for hours; finally climbed down when the first hint of dawn appeared. If ever you take a cruise, do this...

[Fred the Cat]

Milky Way over Bioluminscent Border. Pay attention, people, because this is a sight that you will not find anywhere else in the Universe. Well, the Milky Way will look very much the same from any nearby exoplanet - hey, Proxima Centauri b and d - But the Bioluminescent Border? Forget it.

Oh, I expect that bioluminescent lifeforms are common enough in the Universe, even all over our own galaxy. That's a very simple form of life, which I can easily believe is common. This exact scene? Unique. The bigger picture? Maybe not so much.

A common denominator

[VictorBorun]

I wonder why this bio-light runs blue-to-cyan range.
I mean, if the all the planktoners use the same chemistry, the spectrum function shape must be the same, must it not?

[Chris Peterson]

I wonder why this bio-light runs blue-to-cyan range.
I mean, if the all the planktoners use the same chemistry, the spectrum function shape must be the same, must it not?

There is a wide range of chemistries and colors produced by bioluminescence, from blue to red. In the ocean it's likely that blue/green colors evolved because of the fact that such light penetrates the most deeply in water, so the bioluminescence aligns with light sensors adapted to that environment. The plankton that light up our surface waters normally exist much deeper.

[johnnydeep]

So, about those multiverses Ann mentioned. I have not read all of Tegmark's stuff, but I'm imagining the (or a) Level I multiverse in his hierarchy as a ridiculously large region of "normal" space-time (that is, exactly like the one we exist in) containing an infinite number of smaller regions (like ours) that are each expanding due to the overall cosmic expansion of the larger space-time volume in which they are all embedded. So, I would also imagine that all these smaller regions would be moving ridiculously fast away from each other, with that speed only increasing all the time due to the ever accelerating expansion of the overall humongous space-time volume that contains them all. No?

[beryllium732]

Beautiful image but you really see the galaxy disc and it's dust and H II regions so clearly?

[VictorBorun]

Beautiful image but you really see the galaxy disc and it's dust and H II regions so clearly?

but it was snapshots with exposures 15-25s, getting what human eye (exposure=0.1 s) can't see

[orin stepanek]

I'll never get a screen background; from this;
but it sure is beautiful!

[VictorBorun]

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful!

I wonder if there is a place on Earth where the Plankton Way would be annotated with two different oceans to the left and to the right.
Near Cape of Good Hope?

[johnnydeep]

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful!

Why?

[Chris Peterson]

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful! 8-) 💫 ⭐️ 🌟 ✨

Why?

Aspect ratio?

[orin stepanek]

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful!

Why?

Aspect ratio?

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful!

Why?

Chris has it covered! I'd have to cut it up so much; it just wouldn't look so good & I'd want it to cover the whole screen! I could stretch and skew it so much to make it work with the aspect; but ugh!

[Chris Peterson]

Why?

Aspect ratio?

SeaBlueSky_Horalek_960_annotated.jpg
I'll never get a screen background; from this;
but it sure is beautiful! 8-) 💫 ⭐️ 🌟 ✨

Why?

Chris has it covered! I'd have to cut it up so much; it just wouldn't look so good & I'd want it to cover the whole screen! I could stretch and skew it so much to make it work with the aspect; but ugh! :evil:

It would work as a phone wallpaper, though.

[Fred the Cat]

So, about those multiverses Ann mentioned. I have not read all of Tegmark's stuff, but I'm imagining the (or a) Level I multiverse in his hierarchy as a ridiculously large region of "normal" space-time (that is, exactly like the one we exist in) containing an infinite number of smaller regions (like ours) that are each expanding due to the overall cosmic expansion of the larger space-time volume in which they are all embedded. So, I would also imagine that all these smaller regions would be moving ridiculously fast away from each other, with that speed only increasing all the time due to the ever accelerating expansion of the overall humongous space-time volume that contains them all. No?

To me it’s easy to imagine multiverses. Being a living time machine every choice I make branches into the next multiverse. Do the choices I don’t make exist – that’s the tough question.

[johnnydeep]

Aspect ratio?

Why?

Chris has it covered! I'd have to cut it up so much; it just wouldn't look so good & I'd want it to cover the whole screen! I could stretch and skew it so much to make it work with the aspect; but ugh!

It would work as a phone wallpaper, though.

Or a tablet. Or a PC screen just by taking only the top half of the image. Would still look fine and show all the features.

[johnnydeep]

So, about those multiverses Ann mentioned. I have not read all of Tegmark's stuff, but I'm imagining the (or a) Level I multiverse in his hierarchy as a ridiculously large region of "normal" space-time (that is, exactly like the one we exist in) containing an infinite number of smaller regions (like ours) that are each expanding due to the overall cosmic expansion of the larger space-time volume in which they are all embedded. So, I would also imagine that all these smaller regions would be moving ridiculously fast away from each other, with that speed only increasing all the time due to the ever accelerating expansion of the overall humongous space-time volume that contains them all. No?

To me it’s easy to imagine multiverses. Being a living time machine every choice I make branches into the next multiverse. Do the choices I don’t make exist – that’s the tough question.

Yeah, but that's the Level III multiverse you get via "quantum branching". The Level I is much easier to understand, as it's merely a gargantuanly BIG yet still familiar-to-us "normal" space-time!

[orin stepanek]

SeaBlueSky_Horalek_960

Hey! You know what? It's still Pretty; Thanks guys! Bent out of
shape; but still!

[VictorBorun]

So, about those multiverses Ann mentioned. I have not read all of Tegmark's stuff, but I'm imagining the (or a) Level I multiverse in his hierarchy as a ridiculously large region of "normal" space-time (that is, exactly like the one we exist in) containing an infinite number of smaller regions (like ours) that are each expanding due to the overall cosmic expansion of the larger space-time volume in which they are all embedded. So, I would also imagine that all these smaller regions would be moving ridiculously fast away from each other, with that speed only increasing all the time due to the ever accelerating expansion of the overall humongous space-time volume that contains them all. No?

To me it’s easy to imagine multiverses. Being a living time machine every choice I make branches into the next multiverse. Do the choices I don’t make exist – that’s the tough question.

Yeah, but that's the Level III multiverse you get via "quantum branching". The Level I is much easier to understand, as it's merely a gargantuanly BIG yet still familiar-to-us "normal" space-time!

I wonder how do we know if branching is chaotic. Mathematically the fractal can be regular, like this paper challenge


offtopic. Tried to do it, using a used sheet of paper, scissors and no planning

...

Click to view full size image 1 or image 2