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12/11/2022

AVIATION IMAGINEE - L'avion du futur selon Douglas Rolfe

Avez-vous déjà imaginé votre transport du futur ? C’est l’idée du magazine Popular Science qui a laissé à Douglas Rolfe tout le loisir de créer son avion personnel. Le résultat est plutôt réaliste et bluffant, ce qui peut s’expliquer par le fait qu'en 1944 l’aviation avait déjà fait un grand bon avec la Première et la Seconde Guerre mondiale.

© Douglas Rolfe, juillet 1944, revue Popular Science
FuturaSciences

11/11/2022

ASTRONOMY - Blood Moon, Ice Giant

 2022 November 11

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

Blood Moon, Ice Giant
Image Credit & CopyrightRyan 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

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

Total Lunar Eclipse
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

The featured image shows a complex nebula that is 
more dense and more blue on one side than the other.
Please see the explanation for more detailed information.

The Asymmetric Nebula Surrounding Wolf-Rayet Star 18
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

2022 November 8
The featured image shows a several interacting
spiral galaxies with a bridge of stars and gas connecting
the two brightest galaxies. 
Please see the explanation for more detailed information.

Galaxies: Wild's Triplet from Hubble
Image Credit: ESA/HubbleNASADark Energy Survey/DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURAJ. 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


L’illustration française n’est pas en reste pour imaginer les machines volantes du futur. En 1901, Monnier imaginait la « machine à faire partir l’amant de Madame très vite » du siècle suivant. Bien que le dessin ne montre rien d’autre qu’une hélice agrémentée d’une paire d’ailes, on imagine l’engin équipé d’un moteur extrêmement puissant, capable de faire déguerpir le malheureux avant l’arrivée de Monsieur.

© Monnier

ASTRONOMY - A Total Lunar Eclipse Over Tajikistan

 2022 November 7

A Total Lunar Eclipse Over Tajikistan
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 EagleSwanTrifid, 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


Il est rare d'en voir d'aussi près ! Appartenant à l'espèce Cylindromyia bicolor, cette petite mouche d'une dizaine de millimètres appartient à la famille des Tachinidés. On la trouve en France métropolitaine, dans des prairies ou des lisières de bois. D'une forme très allongée, elle possède un abdomen de couleur rouge principalement, et noir à la base. Mais, sur la photo, ce sont surtout ses yeux qui fascinent ! En comparaison avec ceux d'un humain qui peuvent visualiser 24 images par seconde, la mouche en voit 200 ! Chaque petite facette de son œil consiste en une lentille qui focalise la lumière sur un capteur individuel, l'ommatidie. Son champ de vision lui permet aussi d'avoir des yeux derrière la tête, et elle est sensible aux ultraviolets. Bien que la mouche ne voie pas les plus petits détails, elle est tout de même très difficile à attraper ! 

© Pierre Anquet
FuturaSciences

05/11/2022

MICROPHOTOGRAPHIE - De petits monstres sous vitamine C


Comme des petits monstres tapis dans le noir, ces étranges créatures aux yeux dorés, et irradiant une inquiétante lueur bleue, semblent observer... ceux qui les observent. Sommes-nous transportés sur une planète lointaine peuplée d'êtres diffus ? Ou avons-nous pénétré par magie l'esprit d'un petit garçon un peu trop rêveur ? Qu'importe la réponse. Une fois encore, Marek Miś met ici son talent artistique au service de cette beauté naturelle qui reste trop souvent cachée à nos yeux.

En saisissant tout simplement quelques cristaux d'acide ascorbique magnifiés par une lumière polarisée et un champ sombre, sous un grossissement de 100 fois. L'acide ascorbique... Un nom étrange pour une substance dont l'un des stéréo-isomères nous est pourtant des plus familiers puisqu'il s'agit de la vitamine C. Une vitamine qui participe, entre autres, au bon fonctionnement de notre système immunitaire. Une fonction qui, avec un zeste d'imagination, se voit révélée au grand jour par ce cliché.

Cliché réalisé à l'aide d'un microscope Olympus BH-2 et d'un appareil Pentax K5. 

© Marek Miś
FuturaSciences

ASTRONOMY - Lunar Eclipse at the South Pole

 2022 November 5

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

Lunar Eclipse at the South Pole
Image Credit & CopyrightAman 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

 2025 January 11 An Evening Sky Full of Planets Image Credit &  Copyright :   Dario Giannobile Explanation:  Only Mercury is missing fro...