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15/03/2024

ASTRONOMY - Portrait of NGC 1055

 2024 March 15

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

Portrait of NGC 1055
Image Credit & CopyrightDave Doctor

Explanation: Big, beautiful spiral galaxy NGC 1055 is a dominant member of a small galaxy group a mere 60 million light-years away toward the aquatically intimidating constellation Cetus. Seen edge-on, the island universe spans over 100,000 light-years, a little larger than our own Milky Way galaxy. The colorful, spiky stars decorating this cosmic portrait of NGC 1055 are in the foreground, well within the Milky Way. But the telltale pinkish star forming regions are scattered through winding dust lanes along the distant galaxy's thin disk. With a smattering of even more distant background galaxies, the deep image also reveals a boxy halo that extends far above and below the central bulge and disk of NGC 1055. The halo itself is laced with faint, narrow structures, and could represent the mixed and spread out debris from a satellite galaxy disrupted by the larger spiral some 10 billion years ago.

14/03/2024

SANTé/MEDECINE - Cancer du sein : attention à ces 5 symptômes - Un sein rouge et gonflé, chaud au toucher (1/5)


Cela peut être le signe d’une infection ou d’une inflammation systémique. Chez certaines femmes, la texture de la peau ressemble à celle d’une orange. “Cette texture alvéolée pourrait être un symptôme d’un cancer du sein inflammatoire, une forme rare et agressive de cancer du sein. Pour déterminer la cause de votre symptôme, vous devez contacter votre médecin généraliste pour une évaluation et un diagnostic.”

CaMinteresse

ASTRONOMY - Moon Pi and Mountain Shadow

 2024 March 14

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

Moon Pi and Mountain Shadow
Image Credit & Copyright: Daniel Lopez (El Cielo de Canarias)

Explanation: What phase of the Moon is 3.14 radians from the Sun? The Full Moon, of course. Even though the Moon might look full for several days, the Moon is truly at its full phase when it is Pi radians (aka 180 degrees) from the Sun in ecliptic longitude. That's opposite the Sun in planet Earth's sky. Rising as the Sun set on March 9, 2020, only an hour or so after the moment of its full phase, this orange tinted and slightly flattened Moon still looked full. It was photographed opposite the setting Sun from Teide National Park on the Canary Island of Tenerife. Also opposite the setting Sun, seen from near the Teide volcano peak about 3,500 meters above sea level, is the mountain's rising triangular shadow extending into Earth's dense atmosphere. Below the distant ridge line on the left are the white telescope domes of Teide Observatory. Again Pi radians from the Sun, on March 25 the Full Moon will dim slightly as it glides through Earth's outer shadow in a penumbral lunar eclipse.

13/03/2024

SANTé/MEDECINE - HISTOIRE - 1561 : Ambroise Paré, le père de la chirurgie moderne


Considéré comme le père de la chirurgie moderne, Ambroise Paré est l'inventeur d'instruments chirurgicaux. Il a mis au point la ligature des artères, qui remplacera la cautérisation. En 1561 et 1562, Ambroise Paré publie un ouvrage intitulé Anatomie universelle du corps humain.

© William Holl
FuturaSciences

ASTRONOMY - The Seagull Nebula

 2024 March 13

A starfield features a large nebula, mostly red, partly blue,
which seems to have the shape of a bird. 
Please see the explanation for more detailed information.

The Seagull Nebula
Credit & Copyright: Gianni Lacroce

Explanation: A broad expanse of glowing gas and dust presents a bird-like visage to astronomers from planet Earth, suggesting its popular moniker: the Seagull NebulaThis portrait of the cosmic bird covers a 1.6-degree wide swath across the plane of the Milky Way, near the direction of Sirius, the alpha star of the constellation of the Big Dog (Canis Major). Of course, the region includes objects with other catalog designations: notably NGC 2327, a compact, dusty emission and reflection nebula with an embedded massive star that forms the bird's head. Dominated by the reddish glow of atomic hydrogen, the complex of gas and dust clouds with bright young stars spans over 100 light-years at an estimated 3,800 light-year distance.

12/03/2024

ASTRONOMIE - Exoplanète


Une exoplanète, aussi connue sous le nom de planète extrasolaire, est une planète ne tourne pas autour du Soleil mais qui orbite autour d'une étoile en dehors de notre Système solaire. Le préfixe exo signifie « extérieur », donc une exoplanète est essentiellement une planète extérieure à notre propre Système solaire.

FuturaSciences

ASTRONOMY - A Galaxy-Shaped Rocket Exhaust Spiral

 2024 March 12

A field of snow is shown, lined with trees along the back.
Above the horizon is an unusual white spiral cloud. 
Stars dot the background, and faint green and red aurora
are also visible. 
Please see the explanation for more detailed information.

A Galaxy-Shaped Rocket Exhaust Spiral
Credit & Copyright: Seung Hye Yang

Explanation: What's that over the horizon? What may look like a strangely nearby galaxy is actually a normal rocket's exhaust plume -- but unusually backlit. Although the SpaceX Falcon 9 rocket was launched from Cape Canaveral in FloridaUSA, its burned propellant was visible over a much wider area, with the featured photograph being taken from AkureyriIceland. The huge spaceship was lifted off a week ago, and the resulting spectacle was captured soon afterward with a single 10-second smartphone exposure, before it quickly dissipated. Like noctilucent clouds, the plume's brightness is caused by the Twilight Effect, where an object is high enough to be illuminated by the twilight Sun, even when the observer on the ground experiences the darkness of night. The spiral shape is likely caused by high winds pushing the expelled gas into the shape of a corkscrew, which, when seen along the trajectory, looks like a spiral. Stars and faint green and red aurora appear in the background of this extraordinary image.

11/03/2024

SANTé/MEDECINE - HISTOIRE - La saignée


La saignée était une technique employée pour éliminer les maladies par le prélèvement de sang. Elle est préconisée par les défenseurs de la théorie des humeurs (Hippocrate), mais progressivement abandonnée.

© DR
FuturaSciences

SANTé/MEDECINE - L'IRM pour mesurer le flux sanguin


À partir de données récoltées depuis une analyse IRM d'un organe, il est possible d'en déduire un certain nombre de détails. Ici, il s'agit d'une simulation du flux sanguin dans une artère carotide. En bleu, les zones où le sang s'écoule mal, à cause d'une plaque d'athérome bouchant le vaisseau.

© CNRS Photothèque, Loïc Boussel
FuturaSciences

ASTRONOMY - A Full Plankton Moon

 2024 March 11

Several images of a full moon setting are superposed.
The moon images are nearly white near the top, but turn
orange and then are covered by low clouds near the horizon.
Unusually, the setting moon images line up almost vertically.
In the foreground is a beach with waves illuminated by
blue-glowing plankton.
Please see the explanation for more detailed information.

A Full Plankton Moon
Credit & Copyright: Petr Horálek / Institute of Physics in Opava

Explanation: What glows in the night? This night featured a combination of usual and unusual glows. Perhaps the most usual glow was from the Moon, a potentially familiar object. The full Moon's nearly vertical descent results from the observer being near Earth's equator. As the Moon sets, air and aerosols in Earth's atmosphere preferentially scatter out blue light, making the Sun-reflecting satellite appear reddish when near the horizon. Perhaps the most unusual glow was from the bioluminescent plankton, likely less familiar objects. These microscopic creatures glow blue, it is thought, primarily to surprise and deter predators. In this case, the glow was caused primarily by plankton-containing waves crashing onto the beach. The image was taken on Soneva Fushi IslandMaldives just over one year ago.

ASTRONOMY - Comet C/2025 R2 (SWAN)

2025 September 18 Comet C/2025 R2 (SWAN) Image Credit &  Copyright :   Team Ciel Austral Explanation:  A new visitor  from the outer  So...