Jean-Luc Dauvergne : The Giants of Summer - (Science & Technologie - Astronomy picture of the day)

2020 July 30
The Giants of Summer
Image Credit & Copyright: Jean-Luc Dauvergne

Explanation: As Comet NEOWISE sweeps through northern summer skies, Jupiter and Saturn are shining brightly, near opposition. With Jupiter opposite the Sun on July 14 and Saturn on July 21, the giant planets are still near their closest to planet Earth in 2020. Sharing the constellation Sagittarius they are up all night, and offer their best and brightest views at the telescope. Both captured on July 22 from a balcony in Paris these two sharp telescopic images don't disappoint, showing off what the giant planets are famous for, Saturn's bright rings and Jupiter's Great Red Spot. These giants of the Solar System are worth following during 2020. On December 21, skygazers can watch the once-in-20-year great conjunction of Jupiter and Saturn.

Observador - Portugal : Vacina contre Covid-19 ja està a ser testada nos Estados Unidos (Ciência & Tecnologia - Saude/Medecina)

A vacina desenvolvida pela Moderna, empresa de biotecnologia de Massachussetts, em parceria com o National Institutes of Health, a agência norte-americana de investigação médica, já está a ser testada com a colaboração de 30 mil voluntários, em 87 locais nos Estados Unidos.

Na primeira fase do estudo, os testes mostraram que todos os voluntários apresentaram respostas imunes. O resultado preliminar foi publicado há duas semanas no New England Journal of Medicine e, apesar de desencadear efeitos secundários leves — fadiga, calafrios, dor de cabeça, dor muscular, dor no local da injeção — a resposta imunológica foi positiva.

Nessa altura, os testes foram feitos a apenas 45 adultos saudáveis, com idades entre 18 e 55 anos, que receberam duas vacinas com 28 dias de intervalo. Agora é diferente, com a fase final de testes a envolver 30 mil participantes, incluindo pessoas que estão em grupos de risco — metade recebendo a vacina, de facto, e a outra metade um placebo.

Anthony S. Fauci, o especialista em doenças infecciosas que integra o grupo de trabalhado criado por Donald Trump para lidar com a pandemia, disse em conferência de imprensa, citada pelo Washington Post, que este é “o lançamento de um evento verdadeiramente histórico na história da vacinologia”. Fauci prevê que em nos últimos meses do ano já seja possível saber se a vacina é ou não eficaz.

Em breve deverão começar também outros 30 mil testes em 120 locais por todo o mundo, feitos pela farmacêutica Pfizer, de acordo com o Washigton Post.

Ariel L. Cappelletti : NGC 6188: The Dragons of Ara (Astronomy picture of the day - Science & Technology)

2020 July 28
NGC 6188: The Dragons of Ara
Image Credit & Copyright: Ariel L. Cappelletti

Explanation: Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark and large molecular cloud in the southern constellation Ara, about 4,000 light-years away. Born in that region only a few million years ago, the massive young stars of the embedded Ara OB1 association sculpt the fantastic shapes and power the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas. The featured image accumulated over 10 hours through a backyard telescope in Córdoba, Argentina and was false-colored using the Hubble palette highlighting emission from sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. The field of view spans about four full Moons, corresponding to about 150 light years at the estimated distance of NGC 6188.

Jeff Dai (TWAN) : Tianwen-1 Mission to Mars (Science & Technology - Astronomy picture of the day)

2020 July 26
Tianwen-1 Mission to Mars
Image Credit & Copyright: Jeff Dai (TWAN)

Explanation: On July 23, this Long March 5 heavy-lift rocket rose into a blue morning sky from China's Hainan Island Wenchang Satellite Launch Center. The rocket carried an orbiter, lander, and rover to ask Heavenly Questions on the ambitious Tianwen-1 mission to Mars. In fact Tianwen-1 was the second of three missions scheduled for a July departure to the Red Planet. The United Arab Emirates launched its Amal (Hope) Mars probe on July 19. NASA's launch of its Mars Perseverance Rover from Cape Canaveral Air Force Station, USA is scheduled for July 30. That is the last planned Mars launch for 2020 though. The minimum-energy launch window for an expedition to Mars is coming to a close in 2020 and will reopen in 2022.

Urs Leutenegger : MAGIC NEOWISE (Science & Technology - Astronomy picture of the day)

2020 July 24
MAGIC NEOWISE
Image Credit & Copyright: Urs Leutenegger

Explanation: The multi-mirror, 17 meter-diameter MAGIC telescopes reflect this starry night sky from the Roque de los Muchachos European Northern Observatory on the Canary Island of La Palma. MAGIC stands for Major Atmospheric Gamma Imaging Cherenkov and the telescopes can see the brief flashes of optical light produced in particle air showers as high-energy gamma rays impact the Earth's upper atmosphere. On July 20, two of the three telescopes in view were looking for gamma rays from the center of our Milky Way galaxy. In reflection they show the bright stars of Sagittarius and Scorpius near the galactic center to the southeast. Beyond the segmented-mirror arrays, above the northwest horizon and below the Big Dipper is Comet NEOWISE. NEOWISE stands for Near Earth Object Wide-field Infrared Survey Explorer. That's the Earth-orbiting satellite used to discover the comet designated C/2020 F3, but you knew that.

Korii : Les médicaments anti-âge (Science & Technologie - Santé/Médecine)

Une première vague de médicaments anti-âge est entrée dans sa phase de test sur des êtres humains. Ils ne vous feront –pour l'instant– pas vivre plus longtemps mais cibleront des problèmes de santé spécifiques liés à l'âge. Appelés les «sénolytiques», ces traitements suppriment certaines cellules que l'on accumule avec le temps.

De premiers résultats ont été observés sur des cas d'arthrites dégénératives, et d'autres molécules pourraient s'intéresser aux maladies des yeux, des poumons ou encore à Parkinson et Alzheimer.

Zixuan Lin : The Structured Tails of Comet NEOWISE - (Science & Technology - Astronomy picture of the day)

2020 July 23
The Structured Tails of Comet NEOWISE
Image Credit & Copyright: Zixuan Lin (Beijing Normal U.)

Explanation: What is creating the structure in Comet NEOWISE's tails? Of the two tails evident, the blue ion tail on the left points directly away from the Sun and is pushed out by the flowing and charged solar wind. Structure in the ion tail comes from different rates of expelled blue-glowing ions from the comet's nucleus, as well as the always complex and continually changing structure of our Sun's wind. Most unusual for Comet C/2020 F3 (NEOWISE), though, is the wavy structure of its dust tail. This dust tail is pushed out by sunlight, but curves as heavier dust particles are better able to resist this light pressure and continue along a solar orbit. Comet NEOWISE's impressive dust-tail striations are not fully understood, as yet, but likely related to rotating streams of sun-reflecting grit liberated by ice melting on its 5-kilometer wide nucleus. The featured 40-image conglomerate, digitally enhanced, was captured three days ago through the dark skies of the Gobi Desert in Inner Mongolia, China. Comet NEOWISE will make it closest pass to the Earth tomorrow as it moves out from the Sun. The comet, already fading but still visible to the unaided eye, should fade more rapidly as it recedes from the Earth.

Nasa : La Terre vue de l'Espace - "Les dunes en étoile du Grand Erg Oriental, en Algérie" - (Science & Technologie)

Dans le désert du Sahara algérien, le Grand Erg Oriental se caractérise par ses dunes en étoile de forme pyramidale qui sont façonnées par des vents dont l'orientation ne cesse de changer. Ainsi, d'est en été, les vents tournent en ouest une fois l'hiver venu. C'est la combinaison de ces vents changeant avec les spécificités géographiques de cette région et les tempêtes qui la traversent qui façonnent ces dunes en étoile.

Cette image satellite a été obtenue en associant de la lumière proche infrarouge et visible. Le sable est de couleur ocre, les ombres sont noires ou grises. Les zones bleutées représentent des roches évaporites.

© Nasa

Science & Technologie - La Terre vue de l'Espace : Eruption du mont Saint Helens

Photo prise le 8 mars 2005, une semaine après l'éruption de poussière et de vapeur. La dernière éruption depuis ce réveil du mont Saint Helens datait alors de septembre 2004. La végétation est en vert et la neige en bleu.

© Nasa/GSFC/METI/ERSDAC/JAROS et U.S./Japan Aster Science Team

NASA : Iron in the Butterfly Nebula (Science & Technology - Astronomy picture of the day)

2020 July 21
Iron in the Butterfly Nebula
Image Credit: NASA, ESA, Hubble; Processing & License: Judy Schmidt

Explanation: Can stars, like caterpillars, transform themselves into butterflies? No, but in the case of the Butterfly Nebula -- it sure looks like it. Though its wingspan covers over 3 light-years and its estimated surface temperature exceeds 200,000 degrees, C, the dying central star of NGC 6302, the featured planetary nebula, has become exceptionally hot, shining brightly in visible and ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up was recorded by the Hubble Space Telescope and is reprocessed here to show off the remarkable details of the complex planetary nebula, highlighting in particular light emitted by iron, shown in red. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius). Planetary nebulas evolve from outer atmospheres of stars like our Sun, but usually fade in about 20,000 years.

Somak Raychaudhury : Eclipse under the Bamboo (Science & Technology - Astronomy picture of the day)

                   Eclipse under the Bamboo
Image Credit & Copyright: Somak Raychaudhury (Inter-University Centre for Astronomy & Astrophysics)

Explanation: Want to watch a solar eclipse safely? Try looking down instead of up, though you might discover you have a plethora of images to choose from. For example, during the June 21st solar eclipse this confusing display appeared under a shady bamboo grove in Pune, India. Small gaps between close knit leaves on the tall plants effectively created a network of randomly placed pinholes. Each one projected a separate image of the eclipsed Sun. The snapshot was taken close to the time of maximum eclipse in Pune when the Moon covered about 60 percent of the Sun's diameter. But an annular eclipse, the Moon in silhouette completely surrounded by a bright solar disk at maximum, could be seen along a narrow path where the Moon's dark shadow crossed central Africa, south Asia, and China.

Tom Masterson : Finding NEOWISE - Science & Technology - Astronomy picture of the day

Finding NEOWISE
Image Credit & Copyright: Tom Masterson

Explanation: If you can see the stars of the Big Dipper, you can find comet NEOWISE in your evening sky tonight. After sunset look for the naked-eye comet below the bowl of the famous celestial kitchen utensil of the north and above your northwestern horizon. You're looking for a fuzzy 'star' with a tail, though probably not so long a tail as in this clear sky snapshot taken from Los Padres National Forest in California on the evening of July 16. Recent photographs of C/2020 F3 (NEOWISE) often show this comet's broad dust tail and fainter but separate ion tail extending farther than the eye can follow. Skygazers around the world have been delighted to find NEOWISE, surprise visitor from the outer Solar System.

Christouf Prod - "Hyper tsunami" - Science & Technologie - Tsunami

Youtube : Océan inconnu - Science & Technologie - Océans - Video

Une médecine ultra personnalisée : Maladies génétiques très rares (Science & Technologie - Santé/Médecine)

En médecine, de nouveaux médicaments contre les maladies génétiques très rares sont en train de voir le jour. L'un des premiers cas est celui de Mila Makovec, une jeune fille souffrant d'une maladie génétique unique, qui a reçu un traitement conçu spécifiquement pour elle.

Remplacer, modifier ou supprimer des gènes n'a jamais été aussi facile. Reste à répondre à une question cruciale: qui paiera pour ces médicaments alors qu'ils n'aident à chaque fois qu'une seule personne et demandent de lourds investissements humains?

Philipp Salzgeber, foto-webcam.eu; Text: Adam Block : Comet NEOWISE over the Swiss Alps (Science & Technology - Astronomy picture of the day)

2020 July 15
Comet NEOWISE over the Swiss Alps
Image Credit & Copyright: Philipp Salzgeber, foto-webcam.eu; Text: Adam Block

Explanation: Comet NEOWISE has been wowing photographers around much of the world during dawn and dusk, at the margins of day and night. For the most northern residents of planet Earth, however, the comet circles the North Star and never sets. The night part of this circular arc is apparent in the featured composite of images assembled from a webcam located at a ski resort in the Swiss Alps. Images were selected at 30-minute intervals throughout the night from July 12th -13th. Comet NEOWISE (C/2020 F3) will continue to become more accessible to northern hemisphere observers as its motion places it higher in the sky each evening after sunset over the next few weeks, as it begins its outbound journey. As with all comets, departure from the inner Solar System comes with inevitable fading. Binoculars are the best way to find and observe the comet visually.

Declan Deval : Comet NEOWISE over Stonehenge (Science & Technology - Astronomy picture of the day)

2020 July 14
Comet NEOWISE over Stonehenge
Image Credit & Copyright: Declan Deval Explanation: Have you ever seen a comet? Tonight -- and likely the next few nights -- should be a good chance. Go outside just at sunset and look to your northwest. The lower your horizon, the better. Binoculars may help, but if your sky is cloudless and dark, all you should need is your unaided eyes and patience. As the Sun sets, the sky will darken, and there will be an unusual faint streak pointing diagonally near the horizon. That is Comet NEOWISE. It is a 5-kilometer-wide evaporating dirty iceberg visiting from -- and returning to -- the outer Solar System. As the Earth turns, the comet will soon set, so you might want to take a picture. In the featured image, Comet C/2020 F3 (NEOWISE) was captured two mornings ago rising over Stonehenge in the UK. Discovered with the NASA satellite NEOWISE toward the end of March, Comet NEOWISE has surprised many by surviving its closest approach to the Sun, brightening dramatically, and developing impressive (blue) ion and (white) dust tails. 

Usine Nouvelle : [Made in France] Un masque à la durée de vie illimitée conçu par des PME de Haute-Savoie et Saint-Gobain (Science & Technologie - Santé/Médecine)

Alors que plusieurs médecins appellent à rendre obligatoire le port du masque dans tous les lieux publics clos, en réponse à une légère reprise du nombre de personnes infectées par le coronavirus en France, gros plan sur un projet original. Un masque Made in France sans limite de réutilisation conçu en Haute-Savoie par les PME Precise France et Nanoceram, avec l'aide du spécialiste des matériaux Saint-Gobain.

Avec le déconfinement, une nouvelle plaie apparaît : les masques jetés sur le trottoir. En réponse, deux PME de Haute-Savoie – Precise France, à Peillonnex, et Nanoceram, à Marnaz – développent une solution plus durable : Precimask, un masque basé sur un système de filtration à particule en céramique. Celui-ci peut être stocké 30 ou 40 ans, sans perte d’efficacité...

Lire la suite sur : Usine Nouvelle

Stelvision : "Observez la comète NEOWISE, belle surprise de l’été !" (Science & Technologie)

Programmez vos réveils !

Il faut se lever très tôt pour admirer la belle chevelue : car aux latitudes tempérées de l’hémisphère nord, elle apparaît en fin de nuit durant toute la première quinzaine de juillet… c’est à dire entre 3h et 5h. À partir du 14 juillet, elle deviendra ensuite visible tout au long de la nuit, mais sa magnitude aura sans doute faibli.

À partir du 12 juillet au soir, l’observation à la tombée de la nuit devient possible au dessus de l’horizon nord-ouest après 23h (heure de Paris) pour les latitudes supérieures à 47° nord. En se déplaçant de jour en jour vers la constellation de la Grande Ourse, la comète NEOWISE gagne progressivement en hauteur et devient observable toute la nuit en rasant l’horizon nord, y compris pour les latitudes inférieures (jusqu’à 35° nord). Mais n’attendez pas forcément que la comète soit bien visible le soir pour tenter de la voir : maintenant qu’elle s’éloigne du Soleil, son éclat va progressivement baisser.

La Terre vue de l'Espace : "Hautes dunes dans le désert de Namibie" (Science & Technologie)

ESA, Rosetta, NAVCAM : Comet CG Creates Its Dust Tail (Science & Technology - Astronomy picture of the day)

2020 July 12
Comet CG Creates Its Dust TailImage Credit & License: ESA, Rosetta, NAVCAM

Explanation: Where do comet tails come from? There are no obvious places on the nuclei of comets from which the jets that create comet tails emanate. One of the best images of emerging jets is shown in the featured picture, taken in 2015 by ESA's robotic Rosetta spacecraft that orbited Comet 67P/Churyumov-Gerasimenko (Comet CG) from 2014 to 2016. The picture shows plumes of gas and dust escaping numerous places from Comet CG's nucleus as it neared the Sun and heated up. The comet has two prominent lobes, the larger one spanning about 4 kilometers, and a smaller 2.5-kilometer lobe connected by a narrow neck. Analyses indicate that evaporation must be taking place well inside the comet's surface to create the jets of dust and ice that we see emitted through the surface. Comet CG (also known as Comet 67P) loses in jets about a meter of radius during each of its 6.44-year orbits around the Sun, a rate at which will completely destroy the comet in only thousands of years. In 2016, Rosetta's mission ended with a controlled impact onto Comet CG's surface.

Emmanuel Paoly : Noctilucent Clouds and Comet NEOWISE (Science & Technology - (Astronomy picture of the day)

2020 july 9

Noctilucent Clouds and Comet NEOWISE
Image Credit & Copyright: Emmanuel Paoly

Explanation: These silvery blue waves washing over a tree-lined horizon in the eastern French Alps are noctilucent clouds. From high in planet Earth's mesosphere, they reflect sunlight in this predawn skyscape taken on July 8. This summer, the night-shining clouds are not new to the northern high-latitudes. Comet NEOWISE is though. Also known as C/2020 F3, the comet was discovered in March by the Earth-orbiting Near Earth Object Wide-field Infrared Survey Explorer (NEOWISE) satellite. It's now emerging in morning twilight only just visible to the unaided eye from a clear location above the northeastern horizon.

Le Monde - France - L’origine du coronavirus SARS-CoV-2 (Science & Technologie - Santé/Médecine)

D’où vient ce virus ? La communauté scientifique n’a pas encore tranché la question. Une forte parenté génétique entre le SARS-CoV-2 et des coronavirus prélevés sur des chauves-souris a été constatée. Mais cela n’explique pas tout : les spécialistes estiment qu’un hôte intermédiaire l’a transmis à l’homme, comme c’est souvent le cas. Pour le SRAS et le MERS, par exemple, la civette et le dromadaire avaient été respectivement identifiés comme porteurs intermédiaires.

En ce qui concerne le coronavirus actuel, le pangolin figure actuellement parmi les principaux « suspects », puisqu’il est porteur d’un coronavirus au profil génétique très proche de celui du SARS-CoV-2, mais cette hypothèse reste à confirmer.

Science & Technology - Astronomy picture of the day : Comet NEOWISE over Lebanon:

2020 July 7
Comet NEOWISE over Lebanon
Image Credit & Copyright: Maroun Habib (Moophz)

Explanation: A comet has suddenly become visible to the unaided eye. Comet C/2020 F3 (NEOWISE) was discovered in late March and brightened as it reached its closest approach to the Sun, inside the orbit of Mercury, late last week. The interplanetary iceberg survived solar heating, so far, and is now becoming closer to the Earth as it starts its long trek back to the outer Solar System. As Comet NEOWISE became one of the few naked-eye comets of the 21st Century, word spread quickly, and the comet has already been photographed behind many famous sites and cities around the globe. Featured, Comet NEOWISE was captured over Lebanon two days ago just before sunrise. The future brightness of Comet NEOWISE remains somewhat uncertain but the comet will likely continue to be findable not only in the early morning sky, but also next week in the early evening sky.

Science & Technologie - La Terre vue de l'Espace : La dépression de Turpan (Chine)

La dépression de Turpan, nichée au pied de montagnes de Bogda en Chine, est un mélange étrange de lacs de sel et de dunes de sable. C'est l'un des rares endroits dans le monde qui se trouve en-dessous du niveau de la mer.

© USGS, Nasa

Science & Technology - Astronomy picture of the day : Meeting in the Mesosphere:

2020 July 4
Meeting in the Mesosphere
Image Credit & Copyright: Stephane Vetter (TWAN, Nuits sacrees)

Explanation: A sensitive video camera on a summit of the Vosges mountains in France captured these surprising fireworks above a distant horizon on June 26. Generated over intense thunderstorms, this one about 260 kilometers away, the brief and mysterious flashes have come to be known as red sprites. The transient luminous events are caused by electrical breakdown at altitudes of 50 to 100 kilometers. That puts them in the mesophere, the coldest layer of planet Earth's atmosphere. The glow beneath the sprites is from more familiar lighting though, below the storm clouds. But on the right, the video frames have captured another summertime apparition from the mesophere. The silvery veins of light are polar mesospheric clouds. Also known as noctilucent or night shining clouds, the icy clouds still reflect the sunlight when the Sun is below the horizon.

Science & Technologie - La Terre vue du ciel : Images à couper le souffle

Thomas Pesquet