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12/11/2022
AVIATION IMAGINEE - L'avion du futur selon Douglas Rolfe
11/11/2022
ASTRONOMY - Blood Moon, Ice Giant
2022 November 11
Image Credit & Copyright: Ryan Han
Explanation: On November 8 the Full Moon turned blood red as it slid through Earth's shadow in a beautiful total lunar eclipse. During totality it also passed in front of, or occulted, outer planet Uranus for eclipse viewers located in parts of northern America and Asia. For a close-up and wider view these two images were taken just before the occultation began, captured with different telescopes and cameras from the same roof top in Shanghai, China. Normally very faint compared to a Full Moon, the tiny, pale, greenish disk of the distant ice giant is just to the left of the Moon's edge and about to disappear behind the darkened, red lunar limb. Though only visible from certain locations across planet Earth, lunar occultations of planets are fairly common. But for this rare "lunar eclipse occultation" to take place, at the time of the total eclipse the outer planet had to be both at opposition and very near the ecliptic plane to fall in line with Sun, Earth, and Moon.
10/11/2022
ASTRONOMY - Total lunar eclipse
022 November 10
Image Credit: KPNO / NOIRLab / NSF / AURA / Petr Horalek (Institute of Physics in Opava)
Explanation: The beginning, middle, and end of a journey through planet Earth's colorful umbral shadow is captured in this timelapse composite image of a total lunar eclipse. Taken on November 8 from Kitt Peak National Observatory this eclipse's 1 hour and 25 minute long total phase starts on the right and finishes on the left. Reddened sunlight, scattered into the central shadow by Earth's dusty atmosphere produces the dramatic dark red hues reflected by the lunar disk. For this eclipse, additional reddening is likely due to scattering from ash lingering in the atmosphere after a large volcanic eruption in the southern Pacific earlier this year. Seen at the right and left, the Earth's shadow is still lighter along its edge though. That faint bluish fringe along the lunar limb is colored by sunlight filtered through Earth's stratospheric ozone layer.
09/11/2022
ASTRONOMY - The Asymmetric Nebula Surrounding Wolf-Rayet Star 18
2022 November 9
Image Credit & Copyright: Alex Woronow
Explanation: Why does the nebula around the star WR-18 shine brighter on one side? Also known as NGC 3199, this active star and its surrounding nebula lie about 12,000 light-years away toward the nautical southern constellation of Carina. The featured deep image has been highly processed to bring out filamentary details of the glowing gas in the bubble-shaped nebula. The nebula is about 75 light-years across. Near the nebula's center is a Wolf-Rayet star, WR-18, which is a massive, hot, short-lived star that generates an intense and complex stellar wind. In fact, Wolf-Rayet stars are known to create nebulas with interesting shapes as their powerful winds sweep up surrounding interstellar material. In this case, the bright right edge was initially thought to indicate that a bow shock was being produced as the star plowed through a uniform medium, like a boat through water. Recent measurements and analyses, however, have shown the star is not moving quickly toward the bright edge. A more likely explanation has emerged that the material surrounding the star is not uniform, but clumped and denser near the bright edge.
08/11/2022
ASTRONOMY - Galaxies: Wild's Triplet from Hubble
Image Credit: ESA/Hubble, NASA, Dark Energy Survey/DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA, J. Dalcanton
Explanation: How many galaxies are interacting here? This grouping of galaxies is called the Wild Triplet, not only for the discoverer, but for the number of bright galaxies that appear. It had been assumed that all three galaxies, collectively cataloged as Arp 248, are interacting, but more recent investigations reveal that only the brightest two galaxies are sparring gravitationally: the big galaxies at the top and bottom. The spiral galaxy in the middle of the featured image by the Hubble Space Telescope is actually far in the distance, as is the galaxy just below it and all of the other numerous galaxies in the field. A striking result of these giants jousting is a tremendous bridge of stars, gas, and dust that stretches between them -- a bridge almost 200,000 light-years long. Light we see today from Wild's Triplet left about 200 million years ago, when dinosaurs roamed the Earth. In perhaps a billion years or so, the two interacting galaxies will merge to form a single large spiral galaxy.
07/11/2022
AVIATION IMAGINEE - La machine volante pour faire partir l’amant de Madame
ASTRONOMY - A Total Lunar Eclipse Over Tajikistan
2022 November 7
Video Credit & Copyright: Jean-Luc Dauvergne (Ciel et Espace); Music: Valère Leroy & Sophie Huet (Space-Music)
Explanation: If the full Moon suddenly faded, what would you see? The answer was recorded in a dramatic time lapse video taken during the total lunar eclipse in 2011 from Tajikistan. During a total lunar eclipse, the Earth moves between the Moon and the Sun, causing the moon to fade dramatically. The Moon never gets completely dark, though, since the Earth's atmosphere refracts some light. As the featured video begins, the scene may appear to be daytime and sunlit, but actually it is a nighttime and lit by the glow of the full Moon. As the Moon becomes eclipsed and fades, background stars become visible and here can be seen reflected in a lake. Most spectacularly, the sky surrounding the eclipsed moon suddenly appears to be full of stars and highlighted by the busy plane of our Milky Way Galaxy. The sequence repeats with a closer view, and the final image shows the placement of the eclipsed Moon near the Eagle, Swan, Trifid, and Lagoon nebulas. Nearly two hours after the eclipse started, the moon emerged from the Earth's shadow and its bright full glare again dominated the sky. Later today or tomorrow, depending on your location relative to the International Date Line, a new total lunar eclipse will take place -- with totality being primarily visible over northeastern Asia and northwestern North America.
06/11/2022
MACROPHOTOGRAPHIE - Insectes - Une mouche assez peu commune
05/11/2022
MICROPHOTOGRAPHIE - De petits monstres sous vitamine C
ASTRONOMY - Lunar Eclipse at the South Pole
2022 November 5
Image Credit & Copyright: Aman Chokshi
Explanation: Last May 16 the Moon slid through Earth's shadow, completely immersed in the planet's dark umbra for about 1 hour and 25 minutes during a total lunar eclipse. In this composited timelapse view, the partial and total phases of the eclipse were captured as the Moon tracked above the horizon from Amundsen-Scott South Pole Station. There it shared a cold and starry south polar night with a surging display of the aurora australis and central Milky Way. In the foreground are the BICEP (right) and South Pole telescopes at the southernmost station's Dark Sector Laboratory. But while polar skies can be spectacular, you won't want to go to the South Pole to view the total lunar eclipse coming up on November 8. Instead, that eclipse can be seen from locations in Asia, Australia, the Pacific, the Americas and Northern Europe. It will be your last chance to watch a total lunar eclipse until 2025.
ASTRONOMY - An Evening Sky Full of Planets
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