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14/11/2024

ASTRONOMY - IC 348 and Barnard 3

 2024 November 14

See Explanation.  Clicking on the picture will download
the highest resolution version available.

IC 348 and Barnard 3
Image Credit & CopyrightAshraf Abu Sara

Explanation: A great nebulous region near bright star omicron Persei offers this study in cosmic contrasts. Captured in the telescopic frame the colorful complex of dust, gas, and stars spans about 3 degrees on the sky along the edge of the Perseus molecular cloud some 1000 light-years away. Surrounded by a bluish halo of dust reflected starlight, omicron Persei itself is just left of center. Immediately below it lies the intriguing young star cluster IC 348 recently explored by the James Webb Space Telescope. In silhouette against the diffuse reddish glow of hydrogen gas, dark and obscuring interstellar dust cloud Barnard 3 is at upper right. Of course the cosmic dust also tends to hide newly formed stars and young stellar objects or protostars from prying optical telescopes. At the Perseus molecular cloud's estimated distance, this field of view would span about 50 light-years.

13/11/2024

BIOMES - Madagascar


Dans les forêts des basses terres de Madagascar, une précieuse biodiversité

FuturaSciences

ASTRONOMY - Barred Spiral Galaxy NGC 1365 from Webb

 2024 November 13

See Explanation.  Clicking on the picture will download
the highest resolution version available.

Barred Spiral Galaxy NGC 1365 from Webb
Image Credit: NASAESACSA, Janice Lee (NOIRLab) - Processing: Alyssa Pagan (STScI)

Explanation: A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That's twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope's Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light. Webb's field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy's core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy's central bar. Astronomers suspect the gravity field of NGC 1365's bar plays a crucial role in the galaxy's evolution, funneling gas and dust into a star-forming maelstrom and ultimately feeding material into the active galaxy's central, supermassive black hole.

12/11/2024

MUSIQUE - Antonín dvořák - Sérénade pour cordes en mi majeur (1876)

 

"Sérénade pour cordes en mi majeur"

BIOMES - Canada


Au Canada, il y a aussi des forêts tempérées

FuturaSciences

ASTRONOMY - NGC 6888: The Crescent Nebula

 2024 November 12

A starfield is shown with a unusual textured nebula
in the center colored in brown with blue trimmings. Diffuse
red nebula appear around the edges. In the center is an
opaque brown object. 
Please see the explanation for more detailed information.

NGC 6888: The Crescent Nebula
Image Credit & Copyright: Team ARO

Explanation: How was the Crescent Nebula created? Looking like an emerging space cocoon, the Crescent Nebula, visible in the center of the featured image, was created by the brightest star in its center. A leading progenitor hypothesis has the Crescent Nebula beginning to form about 250,000 years ago. At that time, the massive central star had evolved to become a Wolf-Rayet star (WR 136), shedding its outer envelope in a strong stellar wind, ejecting the equivalent of our Sun's mass every 10,000 years. This wind impacted surrounding gas left over from a previous phase, compacting it into a series of complex shells, and lighting it up. The Crescent Nebula, also known as NGC 6888, lies about 4,700 light-years away in the constellation of Cygnus. Star WR 136 will probably undergo a supernova explosion sometime in the next million years.

11/11/2024

BIOMES - Le Pantanal


Le Pantanal, la plus grande prairie humide de la Planète

FuturaSciences

ASTRONOMY - The Unusual Tails of Comet Tsuchinshan-Atlas

 2024 November 11

A starfield is shown that includes a bright comet.
A bright tail points to the upper right but has an
unusual dark streak in it. A thin anti-tail points
toward the lower left. 
Please see the explanation for more detailed information.

The Unusual Tails of Comet Tsuchinshan-Atlas
Image Credit & Copyright: Bray Falls

Explanation: What created an unusual dark streak in Comet Tsuchinshan-Atlas's tail? Some images of the bright comet during mid-October not only caught its impressively long tail and its thin anti-tail, but a rather unexpected feature: a dark streak in the long tail. The reason for the dark streak is currently unclear and a topic of some debate. Possible reasons include a plume of dark dust, different parts of the bright tail being unusually superposed, and a shadow of a dense part of the coma on smaller dust particles. The streak is visible in the featured image taken on October 14 from Texas, USA. To help future analyses, if you have taken a good image of the comet that clearly shows this dark streak, please send it in to APOD. Comet Tsuchinshan–ATLAS has now faded considerably and is returning to the outer Solar System.

10/11/2024

BIOMES - Le Deadvlei


Le Deadvlei, un marais mort au cœur du désert.

FuturaSciences

ASTRONOMY - Valles Marineris: The Grand Canyon of Mars

 


2024 November 10
A picture of Mars is shown as a large orange globe.
Across the center of the planet a long canyon is visible. 
Please see the explanation for more detailed information.

Valles Marineris: The Grand Canyon of Mars
Image Credit: NASAUSGSViking Project

Explanation: The largest canyon in the Solar System cuts a wide swath across the face of Mars. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris remains unknown, although a leading hypothesis holds that it started as a crack billions of years ago as the planet cooled. Several geologic processes have been identified in the canyon. The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s. 

METEOROLOGIE - Ciel de feu à Barcelone

Ce ciel de feu spectaculaire a été pris en photo à Barcelone en Espagne : on peut y voir des nuages lenticulaires très bien formés, par l&...