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29/07/2024

ASTRONOMY - Milky Way over Uluru

Milky Way over Uluru
Image Credit & Copyright: Max Inwood

Explanation: What's happening above Uluru? A United Nations World Heritage SiteUluru is an extraordinary 350-meter high mountain in central Australia that rises sharply from nearly flat surroundings. Composed of sandstone, Uluru has slowly formed over the past 300 million years as softer rock eroded away. The Uluru region has been a home to humans for over 22,000 years. Recorded last month, the starry sky above Uluru includes the central band of our Milky Way galaxy, complete with complex dark filaments of dust, bright red emission nebulas, and billions of stars.

2024 July 29

28/07/2024

INVENTIONS DE DEMAIN - Le vaccin qui vous fera écraser

 

Un vaccin aidera-t-il les fumeurs à écraser ? Trois sociétés pharmaceutiques ont commencé les essais cliniques d’un vaccin antinicotine. Celui de la société américaine Nabi Pharmaceuticals est le plus avancé. Le NicVAX stimulerait la production d’anticorps qui se lieraient dans le sang à la nicotine et empêcheraient celle-ci de se rendre au cerveau, diminuant ainsi la dépendance du fumeur. Les résultats, pour l’instant, sont comparables à ceux des substituts nicotiniques.

Lactualité

ASTRONOMY - Sun Dance

 2024 July 28

Sun Dance
Video Credit: NASASDOProcessing: Alan Watson via Helioviewer

Explanation: Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer. The dramatic explosion was captured in ultraviolet light in the featured time-lapse video covering about three hours. A looping magnetic field directed the flow of hot plasma on the Sun. The scale of the dancing prominence is huge -- the entire Earth would easily fit under the flowing arch of hot gas. A quiescent prominence typically lasts about a month and may erupt in a Coronal Mass Ejection (CME), expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. Like in 2012, this year the Sun's surface is again quite active and features many filaments and prominences.

27/07/2024

ASTRONOMY - Saturn at the Moon's Edge

 2024 July 27

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

Saturn at the Moon's Edge
Image Credit & CopyrightChengcheng Xu

Explanation: Saturn now rises before midnight in planet Earth's sky. On July 24, the naked-eye planet was in close conjunction, close on the sky, to a waning gibbous Moon. But from some locations on planet Earth the ringed gas giant was occulted, disappearing behind the Moon for about an hour from skies over parts of Asia and Africa. Because the Moon and bright planets wander through the sky near the ecliptic plane, such occultation events are not uncommon, but they can be dramatic. In this telescopic view from Nanjing, Jiangsu, China, Saturn is caught moments before its disappearance behind the lunar disk. The snapshot gives the illusion that Saturn hangs just above Glushko crater, a 43 kilometer diameter, young, ray crater near the Moon's western edge. Of course, the Moon is 400 thousand kilometers away, compared to Saturn's distance of 1.4 billion kilometers.

26/07/2024

SANTé/MEDECINE - Gregory Pincus : créateur de la pilule contraceptive


Gregory Pincus est un endocrinologue américain, né le 9 avril 1903 dans le New Jersey et décédé à Boston le 22 août 1967. Il a travaillé sur les propriétés des stéroïdes dans la fertilité et mis au point la première pilule contraceptive en 1956 ; celle-ci sera mise sur le marché en 1960. L'invention de la pilule contraceptive s'inscrit dans le contexte d'un vaste mouvement féministe aux États-Unis.

© Matthew Bowden, OTRS

ASTRONOMY - Facing NGC 6946

 2024 July 26

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

Facing NGC 6946
Image Credit & CopyrightRoberto Marinoni

Explanation: From our vantage point in the Milky Way Galaxy, we see NGC 6946 face-on. The big, beautiful spiral galaxy is located just 20 million light-years away, behind a veil of foreground dust and stars in the high and far-off constellation Cepheus. In this sharp telescopic portrait, from the core outward the galaxy's colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the loose, fragmented spiral arms. NGC 6946 is also bright in infrared light and rich in gas and dust, exhibiting a high star birth and death rate. In fact, since the early 20th century ten confirmed supernovae, the death explosions of massive stars, were discovered in NGC 6946. Nearly 40,000 light-years across, NGC 6946 is also known as the Fireworks Galaxy.

25/07/2024

SANTé/MEDECINE - Louis Pasteur - père de la vaccination


Louis Pasteur, né à Dole (Jura) le 27 décembre 1822, est un scientifique français, chimiste et physicien de formation, pionnier de la microbiologie et père de la vaccination. Il est connu pour ses travaux sur la fermentation, sur les maladies du vin (travaux à l'origine de la technique de pasteurisation) et pour avoir réfuté la théorie de la génération spontanée. Il est également célèbre pour avoir mis au point le premier vaccin antirabique. Il est décédé à Marnes-la-Coquette le 28 septembre 1895.

© Félix Nadar, CCO

INVENTIONS DE DEMAIN - Ressentez la peur du héros


Le son et l’image plongent les mordus de cinéma au cœur de l’action. Les ingénieurs de la société néerlandaise Philips vont encore plus loin : ils veulent mettre à contribution le sens du toucher des cinéphiles en leur faisant ressentir physiquement les émotions des personnages, grâce à une « veste émotionnelle » bardée de capteurs. L’héroïne est angoissée ? La veste se contracte légèrement pour vous oppresser. Elle a l’estomac noué ? Vous aussi, quand la veste vous serre à cet endroit. Difficile pour l’instant de savoir si elle sera destinée au marché des cinémas ou… des cinémas maison.

Lactualité
(Capital Photos/Frank van Beek)

ASTRONOMY - NGC 7023: The Iris Nebula

2024 July 25
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

NGC 7023: The Iris Nebula
Image Credit & CopyrightRobert Shepherd

Explanation: These cosmic clouds have blossomed 1,300 light-years away in the fertile starfields of the constellation Cepheus. Called the Iris Nebula, NGC 7023 is not the only nebula to evoke the imagery of flowers. Still, this deep telescopic image shows off the Iris Nebula's range of colors and symmetries embedded in surrounding fields of interstellar dust. Within the Iris itself, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the reflection nebula glow with a faint reddish photoluminescence as some dust grains effectively convert the star's invisible ultraviolet radiation to visible red light. Infrared observations indicate that this nebula contains complex carbon molecules known as PAHs. The dusty blue petals of the Iris Nebula span about six light-years. 

24/07/2024

ASTRONOMY - Exaggerated Moon

2024 July 24
Earth's Moon is shown with the heights of surface
features all greatly exaggerated. Also, the colors of the
Moon have been exaggerated so areas of blue and red are
more easily seen. 
Please see the explanation for more detailed information.

Exaggerated Moon
Credit: Data: NASALunar Orbiter Laser Altimeter; Image & Processing: Ildar Ibatullin

Explanation: Our Moon doesn't really have craters this big. Earth's Moon, Luna, also doesn't naturally show this spikey texture, and its colors are more subtle. But this digital creation is based on reality. The featured image is a digital composite of a good Moon image and surface height data taken from NASA's Lunar Orbiter Laser Altimeter (LOLA) mission -- and then exaggerated for educational understanding. The digital enhancements, for example, accentuate lunar highlands and show more clearly craters that illustrate the tremendous bombardment our Moon has been through during its 4.6-billion-year history. The dark areas, called maria, have fewer craters and were once seas of molten lava. Additionally, the image colors, although based on the moon's real composition, are changed and exaggerated. Here, a blue hue indicates a region that is iron rich, while orange indicates a slight excess of aluminum. Although the Moon has shown the same side to the Earth for billions of years, modern technology is allowing humanity to learn much more about it -- and how it affects the Earth

ASTRONOMY - Interplanetary Earth

 2024 November 23 Interplanetary Earth Image Credit:  Cassini Imaging Team ,  SSI ,  JPL ,  ESA ,  NASA  &  NASA  /  JHU Applied Physics...