ASTRONOMIE - Les plus beaux astres de la voie lactée - Mars

Planète externe la plus proche de notre Terre, Mars passionne les astronautes. Cette représentation de la Planète rouge est une mosaïque assemblée à partir d'images prises par l'orbiteur Viking 1 le 22 février 1980. Il s'agit du deuxième vaisseau à se poser sur Mars et à réussir sa mission. On peut apercevoir Valles Marineris, qui fait presque 4.000 km de long.

© Nasa, Wikimedia Commons, DP

VEGETAUX - Cyprès dans la brume - Cyprès chauve - Texas - USA

 

Le sud-est des États-Unis compte de nombreux marais, lacs et bayous où de grands cyprès chauves émergent de l'eau. La photo a été prise depuis un kayak à l'aube brumeuse sur un lac à l'est du Texas.

© Doron Talmi 

ASTRONOMY - Full Moons of August

 2023 August 30

Full Moons of August
Image Credit & Copyright: Gianni Tumino

Explanation: Near perigee, the closest point in its almost moonthly orbit, a Full Moon rose as the Sun set on August 1. Its brighter than average lunar disk was captured in this dramatic moonrise sequence over dense cloud banks along the eastern horizon from Ragusa, Sicily. Illuminating night skies around planet Earth it was the second supermoon of 2023. Yet again near perigee, the third supermoon of 2023 will also shine on an August night. Rising as the Sun sets tonight this second Full Moon in August will be known to some as a Blue Moon, even though scattered sunlight gives the lunar disk a reddened hue. Defined as the second full moon in a calendar month, blue moons occur only once every 2 or 3 years. That's because lunar phases take 29.5 days, almost a calendar month, to go through a complete cycle. Tonight an August Blue Moon will find itself beside bright planet Saturn.

ASTRONOMY - Unusual Spiral Galaxy M66 from Webb

 2023 August 29

Unusual Spiral Galaxy M66 from Webb
Image Credit: NASA, ESA, CSA, JWST; Processing: Brian Tomlinson

Explanation: Why isn't spiral galaxy M66 symmetric? Usually, density waves of gas, dust, and newly formed stars circle a spiral galaxy's center and create a nearly symmetric galaxy. The differences between M66's spiral arms and the apparent displacement of its nucleus are all likely caused by previous close interactions and the tidal gravitational pulls of nearby galaxy neighbors M65 and NGC 3628. The galaxy, featured here in infrared light taken by the James Webb Space Telescope, spans about 100,000 light years, lies about 35 million light years distant, and is the largest galaxy in a group known as the Leo Triplet. Like many spiral galaxies, the long and intricate dust lanes of M66 are seen intertwined with the bright stars and intergalactic dust that follow the spiral arms.

MUSICA - Chris Botti - Ave Maria / Caruso

"Ave Maria / Caruso"

MUSIC - Chris Botti & Yo-Yo Ma - Cinema Paradiso

"Cinema Paradiso"

ASTRONOMY - Star Formation in the Pacman Nebula

 2023 August 28

Star Formation in the Pacman Nebula
Image Credit & Copyright: Craig Stocks

Explanation: Look through the cosmic cloud cataloged as NGC 281 and you might miss the stars of open cluster IC 1590. Formed within the nebula, that cluster's young, massive stars ultimately power the pervasive nebular glow. The eye-catching shapes looming in the featured portrait of NGC 281 are sculpted dusty columns and dense Bok globules seen in silhouette, eroded by intense, energetic winds and radiation from the hot cluster stars. If they survive long enough, the dusty structures could also be sites of future star formation. Playfully called the Pacman Nebula because of its overall shape, NGC 281 is about 10,000 light-years away in the constellation Cassiopeia. This sharp composite image was made through narrow-band filters. It combines emission from the nebula's hydrogen and oxygen atoms to synthesize red, green, and blue colors. The scene spans well over 80 light-years at the estimated distance of NGC 281.

ASTRONOMY - Three Galaxies and a Comet

 2023 August 27

Three Galaxies and a Comet
Credit & Copyright: Miloslav Druckmuller (Brno University of Technology)

Explanation: Diffuse starlight and dark nebulae along the southern Milky Way arc over the horizon and sprawl diagonally through this gorgeous nightscape. The breath-taking mosaic spans a wide 100 degrees, with the rugged terrain of the Patagonia, Argentina region in the foreground. Along with the insider's view of our own galaxy, the image features our outside perspective on two irregular satellite galaxies - the Large and Small Magellanic Clouds. The scene also captures the broad tail and bright coma of Comet McNaught, the Great Comet of 2007.

AERONAUTIQUE - LES INVENTIONS QUI N'ONT JAMAIS VOLE - L'Ariel

Breveté en 1842, l'Ariel est un aéroplane équipé d'un moteur à vapeur très perfectionné pour l'époque. Cinquante mètres d'envergure, 26 mètres de longueur et 10 mètres de largeur d'ailes : cet avion était pour le moins impressionnant. Cependant, lors de son premier essai, le moteur n'a pas résisté à sa taille et l'Ariel n'a jamais pris son envol. William Samuel Henson, découragé, a abandonné le projet.

© Frederick Marriott

ASTRONOMY - Crescents of Venus

 2023 August 26

Crescents of Venus
Image Credit & Copyright: Roberto Ortu

Explanation: Just as the Moon goes through phases, Venus' visible sunlit hemisphere waxes and wanes. This sequence of telescopic images illustrates the steady changes for Venus during its recent 2023 apparition as our evening star. Gliding along its interior orbit between Earth and Sun, Venus grows larger during that period because it is approaching planet Earth. Its crescent narrows though, as the inner planet swings closer to our line-of-sight to the Sun. Closest to the Earth-Sun line but passing about 8 degrees south of the Sun, on August 13 Venus reached its (non-judgmental) inferior conjunction. And now Venus shines above the eastern horizon in predawn skies, completing its transition to planet Earth's morning star. On August 21, NASA's Parker Solar Probe completed its sixth gravity assist flyby of Venus, using the encounter to maneuver the probe toward its closest approach yet to the Sun.