ASTRONOMY - ELT and the Milky Way

 2024 March 16

ELT and the Milky Way
Image Credit & License: European Southern Observatory - Courtesy: Jens Scheidtmann

Explanation: The southern winter Milky Way sprawls across this night skyscape. Looking due south, the webcam view was recorded near local midnight on March 11 in dry, dark skies over the central Chilean Atacama desert. Seen below the graceful arc of diffuse starlight are satellite galaxies of the mighty Milky Way, also known as the Large and Small Magellanic clouds. In the foreground is the site of the European Southern Observatory's 40-metre-class Extremely Large Telescope (ELT). Under construction at the 3000 metre summit of Cerro Armazones, the ELT is on track to become planet Earth's biggest Eye on the Sky.

SANTé/MEDECINE - Cancer du sein : attention à ces 5 symptômes - Une inversion du mamelon (2/5)

 

Un autre signe doit vous interroger : lorsque votre mamelon commence à s’inverser et s’enfoncer vers l’intérieur. Cela peut vouloir dire qu’une tumeur se développe dans le sein et qu’elle tire une partie du tissu mammaire vers elle, indique la médecin.

CaMinteresse

ASTRONOMY - Portrait of NGC 1055

 2024 March 15

Portrait of NGC 1055
Image Credit & Copyright: Dave 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.

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

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.

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

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 Nebula. This 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.

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 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 Florida, USA, its burned propellant was visible over a much wider area, with the featured photograph being taken from Akureyri, Iceland. 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.

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