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04/07/2021

ASTRONOMY - The Face on Mars

 2021 July 4

The picture shows a Martian rock formation nicknamed the Face on Mars.
Please see the explanation for more detailed information.

The Face on Mars
Image Credit: NASAViking 1 Orbiter

Explanation: Wouldn't it be fun if clouds were castles? Wouldn't it be fun if the laundry on the bedroom chair was a superhero? Wouldn't it be fun if rock mesas on Mars were interplanetary monuments to the human face? Clouds, though, are floating droplets of water and ice. Laundry is cotton, wool, or plastic, woven into garments. Famous Martian rock mesas known by names like the Face on Mars appear quite natural when seen more clearly on better images. Is reality boring? Nobody knows why some clouds make rain. Nobody knows if life ever developed on Mars. Nobody knows why the laundry on the bedroom chair smells like root beer. Scientific exploration can not only resolve mysteries, but uncover new knowledge, greater mysteries, and yet deeper questions. As humanity explores our universe, perhaps fun -- through discovery -- is just beginning.

03/07/2021

SANTé/MéDECINE - L'alcool et le foie


Les discours anti-alcool, ça fait plusieurs années que les professionnels de la santé ne cessent d’en faire. Pourtant, le nombre de buveurs continue de grimper et ils sont de plus en plus jeunes. Si l’alcool en soi ne pose pas problème, c’est son excès qui est vivement pointé du doigt en raison de son impact sur la santé notamment le foie, et vous allez vite comprendre pourquoi.

Les toxines d’alcool annihilent le filtre hépatique

Le foie est, avec les reins, l’un des organes qui s’assurent d’assainir notre organisme. L’un de ses rôles est de débarrasser notre organisme des toxines en filtrant le sang et cette fonction de filtre, c’est à cellules que le foie le doit.
Or, la capacité du foie à filtrer les toxines d’alcool est limitée. Plus vous buvez, plus vous acculez votre foie. Ce qui dégrade la capacité à filtrer de ce dernier, conduisant à une inflammation, puis à la mort des cellules hépatiques.

Conséquences de la dégradation du filtre hépatique

Malheureusement, la dégradation des cellules du foie n’est que le début d’un long processus de dégradation. À termes, les buveurs chroniquent et les alcooliques encore plusieurs conséquences graves à savoir :
  • La fibrose qui est une accumulation de tissu cicatriciel dans le foie
  • La cirrhose qui se manifeste par un dysfonctionnement total des fonctions hépatiques.
Il en résulte l’envahissement de votre organisme par les toxiques que le foie n’arrive plus à éliminer.

ASTRONOMY - Along the Milky Way

 2021 July 3

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

Along the Milky Way
Image Credit & Copyright: Rolf Weisenfeld

Explanation: You can't walk along the Milky Way. Still, under a dark sky you can explore it. To the eye the pale luminous trail of light arcing through the sky on a dark, moonless night does appear to be a path through the heavens. The glowing celestial band is the faint, collective light of distant stars cut by swaths of obscuring interstellar dust clouds. It lies along the plane of our home galaxy, so named because it looks like a milky way. Since Galileo's time, the Milky Way has been revealed to telescopic skygazers to be filled with congeries of innumerable stars and cosmic wonders.

02/07/2021

ASTRONOMY - AR2835: Islands in the Photosphere

 2021 July 2

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

AR2835: Islands in the Photosphere
Image Credit & Copyright: Michael Teoh, Heng Ee Observatory, Penang, Malaysia

Explanation: Awash in a sea of incandescent plasma and anchored in strong magnetic fields, sunspots are planet-sized dark islands in the solar photosphere, the bright surface of the Sun. Found in solar active regions, sunspots look dark only because they are slightly cooler though, with temperatures of about 4,000 kelvins compared to 6,000 kelvins for the surrounding solar surface. These sunspots lie in active region AR2835. The largest active region now crossing the Sun, AR2835 is captured in this sharp telescopic close-up from July 1 in a field of view that spans about 150,000 kilometers or over ten Earth diameters. With powerful magnetic fields, solar active regions are often responsible for solar flares and coronal mass ejections, storms which affect space weather near planet Earth.

01/07/2021

ASTRONOMY - Perseverance Selfie with Ingenuity

 2021 July 1

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

Perseverance Selfie with Ingenuity
Image Credit: NASAJPL-CaltechMSSS

Explanation: On sol 46 (April 6, 2021) the Perseverance rover held out a robotic arm to take its first selfie on Mars. The WATSON camera at the end of the arm was designed to take close-ups of martian rocks and surface details though, and not a quick snap shot of friends and smiling faces. In the end, teamwork and weeks of planning on Mars time was required to program a complex series of exposures and camera motions to include Perseverance and its surroundings. The resulting 62 frames were composed into a detailed mosiac, one of the most complicated Mars rover selfies ever taken. In this version of the selfie, the rover's Mastcam-Z and SuperCam instruments are looking toward WATSON and the end of the rover's outstretched arm. About 4 meters (13 feet) from Perseverance is a robotic companion, the Mars Ingenuity helicopter.

PRATIQUE - Enfin une Astuce Pour Que la Grille du Barbecue ne colle plus

Vous en avez assez que de la nourriture reste collée sur la grille du barbecue ? Que ça soit du poisson, comme les sardines, ou de la viande, ça s'accroche toujours sur la grille. Résultat, il faut frotter bien fort pour nettoyer la grille, sinon elle s'encrasse rapidement. Heureusement, il existe un truc incroyable pour que les aliments ne restent plus accrochés sur le bbq. L'astuce est de frotter un oignon sur la grille avant de faire cuire les aliments.

28/06/2021

ASTRONOMY - A Paper Moon Solar Eclipse

 2021 June 28

The picture shows an artistic photograph of a partial solar eclipse.
Please see the explanation for more detailed information.

A Paper Moon Solar Eclipse
Image Credit & Copyright: Wang Letian (Eyes at Night)

Explanation: It may look like a paper Moon. Sailing past a canvas Sun. But those are not cardboard clouds. And it's not make believe.  The featured picture of an orange colored sky is real -- a digital composite of two exposures of the solar eclipse that occurred earlier this month. The first exposure was taken with a regular telescope that captured an overexposed Sun and an underexposed Moon, while the second image was taken with a solar telescope that captured details of the chromosphere of the background Sun. The Sun's canvas-like texture was brought up by imaging in a very specific shade of red emitted by hydrogen. Several prominences can be seen around the Sun's edge. The image was captured just before sunset from XilingolInner MongoliaChina. It's also not make-believe to imagine that the Moon is made of dense rock, the Sun is made of hot gas, and clouds are made of floating droplets of water and ice.

26/06/2021

ASTRONOMY - Pixels in the Sun

 2021 June 26

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

Pixels in the Sun
Image Credit & Copyright: Wang Letian (Eyes at Night)

Explanation: These two panels, composed of video frames made with a safe solar telescope and hydrogen alpha filter, show remarkably sharp details on the solar disk and giant prominences along the Sun's edge on June 6 (top) and June 18. Taken from Beijing, China, they also show a transit of the International Space Station and China's new Tiangong Space Station in silhouette against the bright Sun. The International Space Station is near center in the bottom panel, crossing the solar disk left of bright active region AR2833 and below a large looping solar filament. The Chinese space station is below solar active region AR2827 and right of center in the top panel, seen as a smaller, combined "+" and "-" shape. The pictures of the transiting orbital outposts were taken with the same equipment and at the same pixel scale, with the International Space Station some 492 kilometers away. The Chinese space station was over 400 kilometers from the camera.

24/06/2021

ASTRONOMY - Messier 99

 2021 June 24

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

Messier 99
Image Credit: NASAESAHubbleJanice LeeProcessing & Copyright: Leo Shatz

Explanation: Grand design spiral galaxy Messier 99 looks majestic on a truly cosmic scale. This recently processed full galaxy portrait stretches over 70,000 light-years across M99. The sharp view is a combination of ultraviolet, visible, and infrared image data from the Hubble Space Telescope. About 50 million light-years distant toward the well-groomed constellation Coma Bernices, the face-on spiral is a member of the nearby Virgo Galaxy Cluster. Also cataloged as NGC 4254, a close encounter with another Virgo cluster member has likely influenced the shape of its well-defined, blue spiral arms.

23/06/2021

ASTRONOMY - HD 163296: Jet from a Star in Formation

 2021 June 22

The picture shows the the star forming system HD 163296 as captured by
ALMA and VLT, including a disk and two jets. 
Please see the explanation for more detailed information.

HD 163296: Jet from a Star in Formation
Image Credit: Visible: VLT/MUSE (ESO); Radio: ALMA (ESO/NAOJ/NRAO)

Explanation: How are jets created during star formation? No one is sure, although recent images of the young star system HD 163296 are quite illuminating. The central star in the featured image is still forming but seen already surrounded by a rotating disk and an outward moving jet. The disk is shown in radio waves taken by the Atacama Large Millimeter Array (ALMA) in Chile, and show gaps likely created by the gravity of very-young planets. The jet, shown in visible light taken by the Very Large Telescope (VLT, also in Chile), expels fast-moving gas -- mostly hydrogen -- from the disk center. The system spans hundreds of times the Earth-Sun distance (au). Details of these new observations are being interpreted to bolster conjectures that the jets are generated and shaped, at least in part, by magnetic fields in the rotating disk. Future observations of HD 163296 and other similar star-forming systems may help fill in details.

SANTé/MEDECINE - A la découverte de l'oreille - Étrier droit - vue antérieure

L'enclume (en vert) s'articule avec l'étrier (en jaune) dans la chaîne des osselets de l'oreille. Au niveau de l'étrier,...