Bernard Valeur

For #molluscmonday the the red-lined bubble snail (Bullina lineata). Although delicate looking, they are voracious predators on small worms.

Hypnotic photo of a curtain aurora that truly looks like a flying dragon.The image is extraordinary: an enormous serpentine green shape twisting through the night sky above a snow-covered landscape, with tiny human silhouettes that emphasize the epic scale. It looks like something straight out of a fantasy story, yet it is completely real.

🧵
'Dragon Aurora over Norway' is an enchanting pic showing an impressive auroral curtain, captured by Marco Bastoni above Tromsø in Northern Norway.

The aurora's glittering green glow somehow reminds of a large dragon. 🔭

➡️ apod.nasa.gov/apod/ap18041...

🧪 ⚛️ #sciart #astrophotography #science

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Le saviez-vous ?
La médaille d'or des Jeux olympiques contient 6 g d'or et 500 g d'argent.
Elle vaut 1640 €... sans compter sa valeur symbolique et affective.

The Cone Nebula This is the iconic pillar in NGC 2264, ~2,500 away in Monoceros, rising from a fiery red sea. It looks dark and monstrous against a glowing crimson hydrogen backdrop, blue crest shining with scattered stars. Hits me hard every time—how stars savage the gas cloud to shape it, yet spark brand-new suns in the exact same chaos. Total proof the cosmos is raw, alive, and insanely gorgeous. Source: https://esahubble.org/images/heic0206f/ Credits: NASA, H. Ford (JHU), G. Illingworth (UCSC/LO), M. Clampin (STScI), G. Hartig (STScI), the ACS Science Team, and ESA.

Mystic Mountain in the Carina Nebula This picture never fails to mess with me—like I’ve accidentally stepped into some brutal, jagged fantasy landscape that’s actively on fire. Hubble snagged it in 2010: a rough spike of gas & dust lost in the insane storm that is the Carina Nebula, sitting about 7,500 light-years out. Tiny new stars are losing their minds inside, shooting Herbig-Haro jets everywhere like they’re trying to escape. At the same time the monster stars right next door are sandblasting the whole thing with radiation, eating the edges away. The palette is ridiculous—sharp electric blue oxygen, warm green-gold from hydrogen and nitrogen, angry red sulfur glowing through it all. Feels straight-up like a Tolkien mountain caught in an apocalypse, pure violent energy. Just stars being born the hard way, screaming into existence. Wild. Source: https://science.nasa.gov/asset/hubble/hubble-captures-view-of-mystic-mountain/ Credits: NASA, ESA, M. Livio and the Hubble 20th Anniversary Team (STScI).

The Veil Nebula This pic always creeps me out in the best way—like catching the faint leftover smoke from a star that blew up around 8,000 years ago. It was a heavy one, roughly 20× our Sun, and now we’ve got this huge expanding shell called the Cygnus Loop, about 2,100 light-years out. Spreads over 110 light-years and still racing away at insane speed. When Hubble gets close you see these thin, wispy threads curling everywhere: soft blue-green oxygen, red hydrogen, some sulfur mixed in—looks like torn lace or drifting cosmic smoke. Quietly brutal. All that’s left of a massive star, yet those threads are basically planting the seeds for the next round of planets and suns. Eerie, gorgeous, and kind of humbling. Source: https://science.nasa.gov/image-detail/veil-nebula/ Credits: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

NGC 2014 and NGC 2020 in the Large Magellanic Cloud (Cosmic Reef) Way out in the Large Magellanic Cloud—163,000 light-years from home—you see this big angry red patch (NGC 2014) getting blasted bright by a bunch of really heavy stars, 10–20 times our Sun’s size. Then, right next to it, that perfect electric-blue bubble (NGC 2020) carved clean by one single Wolf-Rayet monster throwing out 200,000× the Sun’s light. The reds/oranges scream hydrogen + nitrogen; the sharp blue ring is oxygen going nuts. Looks exactly like some underwater coral reef… except the whole scene is only about 5 million years old. Source: https://science.nasa.gov/asset/hubble/cosmic-reef/ Credits: NASA, ESA and STScI

"...it's a mysterious and marvelous fact that our universe obeys laws of nature that always turn out to be expressible in the language of calculus as sentences called differential equations."

— Steven Strogatz, 'Infinite Powers'

🔭 🧪 #Hubble images' description, sources, credits in the ALT text

volcan etna en éruption de nuit

Vous voulez du beau aujourd'hui ?

Voici l'Etna (Sicile) photographié par Gianluca Gianferrari lauréat du grand prix photo de HIPA.
😍

"Je suis de ceux qui pensent que la science est d'une grande beauté.

Un scientifique dans son laboratoire est, non seulement un technicien, il est aussi un enfant placé devant des phénomènes naturels qui l'impressionnent comme des contes de fées."

Marie Curie

You can also see History of Quantim Dots
➡️ youtu.be/6qEWG8xu6wQ?...

Thamserku right there, all snowy and razor-sharp in Nepal, and above it this cloud that looks straight out of a dream. Pale pink, light green, turquoise fading into almost-nothing violet, all happening along the edges—like the light just shattered into little colored bits.It's not a full rainbow, nah, just pieces of one. Tiny tiny droplets, all the same size, scattering the sun in exactly that way. The mountain underneath stays freezing, white and icy blue, but the cloud is glowing warm, almost unreal, with that low sun hitting it from behind.

🧵
Do you know the effect called cloud iridescence or irisation?🧪

When parts of clouds are thin and have similar size droplets, diffraction can make them shine with colours like a corona.🔭

In fact, the colours are essentially corona fragments. ⚛️

➡️ apod.nasa.gov/apod/ap14070...

#sky #Nature

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Le vert des plumes d'oiseaux résulte de la superposition du jaune d'un pigment et du bleu structurel résultant de la diffusion de la lumière par les barbules.
C'est le cas notamment de la perruche verte. Si le pigment jaune n'est pas produit en raison d'une mutation génétique, la perruche est bleue.

A rainbow of red light over land

A rainbow of red light over land

Just observed a “red rainbow”, a rainbow of atmospherically refracted red/orange light just prior to sunrise.

📸 @stephanieg3.bsky.social

Dans ce débat sur La nuit étoilée de Van Gogh, on oublie de dire que ce peintre, passionné d’astronomie, lisait régulièrement la revue L’Astronomie, éditée par son ami Camille Flammarion, revue dans laquelle figuraient des représentations de "nébuleuses cosmiques". Son inspiration vient de là !

Trois choses à savoir sur les aurores boréales

Que se cache-t-il derrière les aurores boréales ?
Jean Lilensten, astronome et planétologue, décrypte les trois choses à savoir pour comprendre les aurores boréales.

Merci d'avoir pensé à moi !
N'étant pas abonné à Sciences et Avenir, je ne peux pas me procurer cet article, mais je dispose d'une large documentation sur ce sujet que j'ai traité en détail dans mon livre "Lumière et luminescence".

Color isn’t real the way you think it is.

It’s a private hallucination your brain creates from three cleverly overlapping sensors in your eyes.

The author explains it so cleanly it hurts (in a good way).

150th color post. Don’t miss it.🧪 ⚛️

#ColorPerception #Optics #Light #Science #VisionScience

Thank you so much for your nice comments on my post.

Slender glowing ribbon of gas, tilted like a narrow pencil, stretches diagonally through the deep space. Delicate red and blue threads weave and shimmer along its sharp form, brightest at the upper-right tip. Distant stars dot the void behind, dominated by the red of ionized hydrogen.

What is this? Maybe a painting?

No!

It's about NGC 2736, or Pencil Nebula, a small part of the Vela Supernova Remnant. 🔭

It's thought to be formed from part of its shock wave, plowing through interstellar space at over 500,000 km per hour!

Image by Greg Turgeon & Utkarsh Mishra

🧪 #science 1/3

Rien d'autre qu'un nuancier pour la couture.

La Lune et le Soleil sont chacun entourés d'un ensemble complexe de halos de glace sur ces photos du ciel au-dessus de Chamonix-Mont-Blanc, et enregistrées une nuit (à gauche) et le lendemain, à la fin du mois de décembre 2025.

La réflexion de la lumière dans les particules de glace en suspension dans l'atmosphère donnent parfois lieu à des phénomènes lumineux magnifiques entourant la Lune ou le Soleil (ci-dessous).

On les appelle respectivement parasélènes et parhélies.

www.cidehom.com/apod.php?_da...

Que sont les couleurs ? Retour aux fondamentaux Pour le 150ème billet de ce blog consacré aux couleurs, il n’est pas inutile de revenir aux fondamentaux, car force est de constater que les propos sur le concept de couleur sont souvent imprécis e…

QUE SONT LES COULEURS ?
Vaste question d’une immense difficulté.
Pour le 150ème billet de mon blog consacré aux couleurs, un retour aux fondamentaux me paraît utile.
⤵️ tinyurl.com/yszsbec8

Tous mes vœux pour une très belle année haute en couleur !

📷 B. Valeur

Trees on a hilltop are seen in a starry sky but with clouds on the far horizon. A strange red circular band of light is seen in the sky. Near this band's center, some bright jellyfish like structures are visible. Please see the explanation for more detailed information.

🔭 Red Sprites and Circular Elves Lightning over Italy

Image Credit & Copyright: Valter Binotto

apod.nasa.gov/apod/ap25122...

The image shows a celestial spectacle over Manitoba, Canada, on a cold winter morning. The moonlight, refracted, reflected and diffracted by millions of falling ice crystals, creates extraordinary optical phenomena. At the center, the Moon is surrounded by a colored halo, called the corona, generated by the diffraction of small droplets of water or ice. A 22-degree halo is seen around it, formed by the refraction of moonlight through six-sided cylindrical ice crystals. On either side of the moon are "moon dogs," bright spots caused by the refraction of light through thin, hexagonal ice plates floating toward the ground. Above and below the 22-degree halo are upper and lower tangent arcs, created by refraction through nearly horizontal ice cylinders. The sky, captured in three combined exposures, appears surreal, transforming the moon into an icon of another world.

🔭 🧪 ⚛️ #sciart

This breathtaking photo by Brent Mckean features a few atmospheric optics phenomena due to refraction, reflection and diffraction of moonlight from millions of falling ice crystals.

Image source➡️ apod.nasa.gov/apod/ap20022...

L'histoire des boîtes quantiques YouTube video by C2N Centre de Nanosciences et de Nanotechnologies

History of Quantum Dots: It was a pleasure to collaborate to this movie on the history of quantum dots. Produced as part of of the PÉPITES program of the French Optical Society, SFO. @c2n-nanos.bsky.social

youtu.be/p89chOVElSA?...

In a Finnish myth, when an arctic fox runs so fast that its bushy tail brushes the mountains, flaming sparks are cast into the heavens creating the northern lights. In fact the Finnish word "revontulet", a name for the aurora borealis or northern lights, can be translated as fire fox. So that evocative myth took on a special significance for the photographer of this northern night skyscape from Finnish Lapland near Kilpisjarvi Lake. The snowy scene is illuminated by moonlight. Saana, an iconic fell or mountain of Lapland, rises at the right in the background. But as the beautiful nothern lights danced overhead, the wild fire fox in the foreground enthusiastically ran around the photographer and his equipment, making it difficult to capture in this lucky single shot.

🔭 Northern Fox Fires

Image Credit & Copyright: Dennis Lehtonen

apod.nasa.gov/apod/ap25121...

Merci de m'avoir signalé cet article !

Un article qui va plaire à @bvaleur.bsky.social

2 anecdotes #louphoques 🐺🦭 :

- c'est actuellement le meilleur rendement connu pour la production de lumière

- l'enzyme et la molécule mises en jeu dans le processus doivent leur nom à Lucifer : "le porteur de lumière"

Trois choses à savoir sur les coraux A l’heure où la communauté scientifique tire la sonnette d’alarme concernant la survie des coraux et le maintien des écosystèmes marins, Serge Plane, écologue

A l’heure où la communauté scientifique tire la sonnette d’alarme concernant la survie des coraux et le maintien des écosystèmes marins, Serge Plane, écologue 🌊 🪸

Sur Mars, le ciel ocre se colore de bleu lorsque les couchers de soleil.

The matte flowers of A. majus (A) and C. bipinnatus (F) and the glossy flowers of Ranunculus repens (K) and Anthurium andraeanum (P) are analyzed. Cross sections show the cone-shaped (B and G) or flat (L and Q) epidermal cells.

A new #ScienceAdvances study finds glossiness helps flowers attract bumblebees from a distance—but at a cost to color up close. https://scim.ag/4oe2JUv

Réponse de l'image-mystère :

Que se passe-t-il lorsque l’on injecte un laser multicolore dans un film de savon de quelques centaines de nanomètres d’épaisseur?
La lumière du laser se ramifie au contact du film et les différentes composantes colorées se séparent pour former un bouquet bariolé.

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