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15/08/2022

ASTRONOMY - The Cygnus Wall of Star Formation

 2022 August 15

The featured image shows the Cygnus Wall of star formation,
a jagged line of bright gas and dark dust set in blue background
and near very dark expanse of dark dust.
Please see the explanation for more detailed information.

The Cygnus Wall of Star Formation
Image Credit & Copyright: Johan Bogaerts

Explanation: The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as Central America and Mexico is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall. The featured image shows the star forming wall lit and eroded by bright young stars, and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 15 light years and lies about 1,500 light years away toward the constellation of the Swan (Cygnus).

14/08/2022

ASTRONOMY - 4000 Exoplanets

 2022 August 14

4000 Exoplanets
Video Credit: SYSTEM Sounds (M. RussoA. Santaguida); Data: NASA Exoplanet Archive

Explanation: Over 4000 planets are now known to exist outside our Solar System. Known as exoplanets, this milestone was passed last month, as recorded by NASA's Exoplanet Archive. The featured video highlights these exoplanets in sound and light, starting chronologically from the first confirmed detection in 1992 and continuing into 2019. The entire night sky is first shown compressed with the central band of our Milky Way Galaxy making a giant U. Exoplanets detected by slight jiggles in their parents-star's colors (radial velocity) appear in pink, while those detected by slight dips in their parent star's brightness (transit) are shown in purple. Further, those exoplanets imaged directly appear in orange, while those detected by gravitationally magnifying the light of a background star (microlensing) are shown in green. The faster a planet orbits its parent star, the higher the accompanying tone played. The retired Kepler satellite has discovered about half of these first 4000 exoplanets in just one region of the sky, while the TESS mission is on track to find even more, all over the sky, orbiting the brightest nearby stars. Finding exoplanets not only helps humanity to better understand the potential prevalence of life elsewhere in the universe, but also how our Earth and Solar System were formed.

ASTRONOMY - Herschel Crater on Mimas

 2022 August 13

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

Herschel Crater on Mimas
Image Credit Cassini Imaging TeamISSJPLESANASA

Explanation: Mimas, small 400 kilometer-diameter moon of Saturn, is host to 130 kilometer-diameter Herschel crater, one of the larger impact craters in the entire Solar System. The robotic Cassini spacecraft orbiting Saturn in 2010 recorded this startling view of small moon and big crater while making a 10,000-kilometer record close pass by the diminutive icy world. Shown in contrast-enhanced false color, the image data reveal more clearly that Herschel's landscape is colored slightly differently from heavily cratered terrain nearby. The color difference could yield surface composition clues to the violent history of Mimas. Of course, an impact on Mimas any larger than the one that created the 130-kilometer Herschel might have destroyed the small moon of Saturn.

12/08/2022

MERVEILLEUX MONDE SOUS-MARIN - Ponte de gorgone rouge


Méditerranée - France - Archipel des Iles d'Hyères - Ile du Levant.

Ponte de gorgone rouge (Paramuricea clavata - Purple gorgonian).

© Alexis Rosenfeld

ASTRONOMY - Portrait of the Eagle Nebula

 2022 August 12

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

Portrait of the Eagle Nebula
Image Credit & CopyrightCharles Bonafilia

Explanation: A star cluster around 2 million years young surrounded by natal clouds of dust and glowing gas, Messier 16 (M16) is also known as The Eagle Nebula. This beautifully detailed image of the region adopts the colorful Hubble palette and includes cosmic sculptures made famous in Hubble Space Telescope close-ups of the starforming complex. Described as elephant trunks or Pillars of Creation, dense, dusty columns rising near the center are light-years in length but are gravitationally contracting to form stars. Energetic radiation from the cluster stars erodes material near the tips, eventually exposing the embedded new stars. Extending from the ridge of bright emission left of center is another dusty starforming column known as the Fairy of Eagle Nebula. M16 lies about 7,000 light-years away, an easy target for binoculars or small telescopes in a nebula rich part of the sky toward the split constellation Serpens Cauda (the tail of the snake). As framed, this telescopic portrait of the Eagle Nebula is about 70 light-years across.

11/08/2022

MUSIC - Franz Schubert - Marche militaire

"Marche militaire"

ASTRONOMY - Perseids and MAGIC

 2022 August 11

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

Perseids and MAGIC
Image Credit & CopyrightUrs Leutenegger

Explanation: On August 11, 2021 a multi-mirror, 17 meter-diameter MAGIC telescope reflected this starry night sky from the Roque de los Muchachos European Northern Observatory on the Canary Island of La Palma. MAGIC stands for Major Atmospheric Gamma Imaging Cherenkov. The telescopes can see the brief flashes of optical light produced in particle air showers as high-energy gamma rays impact the Earth's upper atmosphere. To the dark-adapted eye the mirror segments offer a tantalizing reflection of stars and nebulae along the plane of our Milky Way galaxy. But directly behind the segmented mirror telescope, low on the horizon, lies the constellation Perseus. And on that date the dramatic composite nightscape also captured meteors streaming from the radiant of the annual Perseid meteor shower. This year the Perseid shower activity will again peak around August 13 but perseid meteors will have to compete with the bright light of a Full Moon.

10/08/2022

ASTRONOMY - Dust Clouds of the Pacman Nebula

 2022 August 10

The featured image shows the interstellar dust structures that 
occur on in interior of NGC 281, the Pacman Nebula. The
dark structures are seen against a red glowing background.
Please see the explanation for more detailed information.

Dust Clouds of the Pacman Nebula
Image Credit & Copyright: Douglas J. Struble (Future World Media)

Explanation: Stars can create huge and intricate dust sculptures from the dense and dark molecular clouds from which they are born. The tools the stars use to carve their detailed works are high energy light and fast stellar winds. The heat they generate evaporates the dark molecular dust as well as causing ambient hydrogen gas to disperse and glow red. Pictured here, a new open cluster of stars designated IC 1590 is nearing completion around the intricate interstellar dust structures in the emission nebula NGC 281, dubbed the Pac-man Nebula because of its overall shape. The dust cloud on the upper left is classified as a Bok Globule as it may gravitationally collapse and form a star -- or stars. The Pacman Nebula lies about 10,000 light years away toward the constellation of Cassiopeia.

09/08/2022

SANTé/MéDECINE - Les vertus du cannabidiol (CBD)


Difficile de passer à côté de la popularité du cannabidiol. Depuis pas mal d’années maintenant, cet extrait issu du chanvre voit sa notoriété monter en flèche, notamment car il se présente sous diverses formes et offre des vertus non négligeables. Parmi elles, la capacité à relaxer et détendre la personne qui en consomme. Mais pas seulement : problèmes d’articulations, douleurs musculaires, manque de sommeil, crises d’angoisse à répétition…consommé régulièrement et à dose raisonnable, le CBD peut avoir un impact positif sur de nombreux problèmes que l’on rencontre au quotidien, jour et nuit. Pour tester les effets procurés par le CBD, partez à sa rencontre. Dans les grandes lignes l'huile composée à 12% de CBD et quasiment dépourvue de THC, aide à se défaire de l’anxiété et du stress, et de retrouver un sommeil profond, le tout naturellement et sans addiction.

MUSIQUE CLASSIQUE - Frederic Chopin - Tristesse

"Tristesse"

AERONAUTIQUE - La grande épopée des ballons dirigeables - 1904 : Baldwin's Airship

Né en 1854, Thomas Scott Baldwin a commencé sa carrière comme serre-freins dans une compagnie de chemin de fer de l'Illinois (États-Uni...