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22/10/2023

ASTRONOMY - Ghost Aurora over Canada

 2023 October 22

A landscape is pictured with snow and a line of evergreen
trees. In the sky is a field of stars but also notable
green aurora. The largest aurora appears similar in form
to a Halloween ghost,
Please see the explanation for more detailed information.

Ghost Aurora over Canada
Image Credit & Copyright: Yuichi TakasakaTWAN

Explanation: What does this aurora look like to you? While braving the cold to watch the skies above northern Canada early one morning in 2013, a most unusual aurora appeared. The aurora definitely appeared to be shaped like something, but what? Two ghostly possibilities recorded by the astrophotographer were "witch" and "goddess of dawn", but please feel free to suggest your own Halloween-enhanced impressions. Regardless of fantastical pareidolic interpretations, the pictured aurora had a typical green color and was surely caused by the scientifically commonplace action of high-energy particles from space interacting with oxygen in Earth's upper atmosphere. In the image foreground, at the bottom, is a frozen Alexandra Falls, while evergreen trees cross the middle.

21/10/2023

ASTRONOMY - Quarter Moons

 023 October 21

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

Quarter Moons
Image Credit & Copyright: Marcella Giulia Pace

Explanation: Half way between New Moon and Full Moon is the Moon's first quarter phase. That's a quarter of the way around its moonthly orbit. At the first quarter phase, half the Moon's visible side is illuminated by sunlight. For the Moon's third quarter phase, half way between Full Moon and New Moon, sunlight illuminates the other half of the visible lunar disk. At both first and third quarter phases, the terminator, or shadow line separating the lunar night and day, runs down the middle. Near the terminator, long shadows bring lunar craters and mountains in to sharp relief, making the quarter phases a good time to observe the Moon. But in case you missed some, all the quarter phases of the Moon and their calendar dates during 2022 can be found in this well-planned array of telephoto images. Of course, you can observe a first quarter Moon tonight.

20/10/2023

SANTE/MEDECINE - Le CBD et le Sommeil (3/3)

Les avantages du CBD sous forme de tisane

Le principal atout de l’infusion de CBD est son goût agréable puisque sous d’autres aspects la saveur peut sembler amer chez certains consommateurs. D’ailleurs, la plante de chanvre est souvent couplée avec d’autres plantes reconnues pour favoriser la détente et la relaxation, ce qui aurait pour effet de décupler les bénéfices. On pense notamment à la verveine qui aide à lutter contre l’anxiété, à la camomille qui a des vertus apaisantes ou encore au tilleul qui facilite l’endormissement. Les infusions aromatisées (aux fruits ou aux légumes) permettent aussi de varier les saveurs et les senteurs.

La préparation est on ne peut plus simple : quelques grammes de tisane à infuser dans de l’eau frémissante entre 5 et 10 minutes selon les recommandations et vous pourrez déguster votre boisson chaude pour absorber naturellement tous ses principes actifs. Pour en maximiser les effets, il est conseillé d’ajouter un peu de matière grasse comme un soupçon de beurre, du lait ou encore de l’huile végétale.

De plus, la consommation de tisane est facile à intégrer dans une routine quotidienne en prenant 1 à 3 tasses au cours de la journée, la dernière étant bien souvent associée au rituel du soir. Il suffit alors de s’installer confortablement pour boire votre boisson chaude, idéalement en limitant les écrans avant le coucher.

FuturaSciences

ASTRONOMY - Galaxies and a Comet

 2023 October 20

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

Galaxies and a Comet
Image Credit & Copyright: Dan Bartlett

Explanation: Galaxies abound in this sharp telescopic image recorded on October 12 in dark skies over June Lake, California. The celestial scene spans nearly 2 degrees within the boundaries of the well-trained northern constellation Canes Venatici. Prominent at the upper left 23.5 million light-years distant is big, beautiful spiral galaxy NGC 4258, known to some as Messier 106. Eye-catching edge-on spiral NGC 4217 is above and right of center about 60 million light-years away. Just passing through the pretty field of view is comet C/2023 H2 Lemmon, discovered last April in image data from the Mount Lemmon Survey. Here the comet sports more of a lime green coma though, along with a faint, narrow ion tail stretching toward the top of the frame. This visitor to the inner Solar System is presently less than 7 light-minutes away and still difficult to spot with binoculars, but it's growing brighter. Comet C/2023 H2 Lemmon will reach perihelion, its closest point to the Sun, on October 29 and perigee, its closest to our fair planet, on November 10 as it transitions from morning to evening northern skies.

19/10/2023

ASTRONOMY - Dust and the Western Veil Nebula

 2023 October 18

Brown glowing dust appears to the left of the blue and 
red filamentary gas that composes the western edge of the
Veil Nebula, a supernova remnant. 
Please see the explanation for more detailed information.

Dust and the Western Veil Nebula
Image Credit & Copyright: Jiang Wu

Explanation: It's so big it is easy to miss. The entire Veil Nebula spans six times the diameter of the full moon, but is so dim you need binoculars to see it. The nebula was created about 15,000 years ago when a star in the constellation of the Swan (Cygnus) exploded. The spectacular explosion would have appeared brighter than even Venus for a week - but there is no known record of it. Pictured is the western edge of the still-expanding gas cloud. Notable gas filaments include the Witch's Broom Nebula on the upper left near the bright foreground star 52 Cygni, and Fleming's Triangular Wisp (formerly known as Pickering's Triangle) running diagonally up the image middle. What is rarely imaged -- but seen in the featured long exposure across many color bands -- is the reflecting brown dust that runs vertically up the image left, dust likely created in the cool atmospheres of massive stars.

17/10/2023

ASTRONOMY - PDS 70: Disk, Planets, and Moons

 2023 October 17

An orange elliptical ring is shown that is a disk of
gas and dust around the star PDS 70. In the center of the disk
is a fuzzy spot and near the inner right edge of the disk is
another fuzzy spot. 
Please see the explanation for more detailed information.

PDS 70: Disk, Planets, and Moons
Image Credit: ALMA (ESO/NAOJ/NRAO); M. Benisty et al.

Explanation: It's not the big ring that's attracting the most attention. Although the big planet-forming ring around the star PDS 70 is clearly imaged and itself quite interesting. It's also not the planet on the right, just inside the big disk, that’s being talked about the most. Although the planet PDS 70c is a newly formed and, interestingly, similar in size and mass to Jupiter. It's the fuzzy patch around the planet PDS 70c that's causing the commotion. That fuzzy patch is thought to be a dusty disk that is now forming into moons -- and that had never been seen before. The featured image was taken in 2021 by the Atacama Large Millimeter Array (ALMA) of 66 radio telescopes in the high Atacama Desert of northern Chile. Based on ALMA data, astronomers infer that the moon-forming exoplanetary disk has a radius similar to our Earth's orbit, and may one day form three or so Luna-sized moons -- not very different from our Jupiter's four.

SANTE/MEDECINE - Le CBD et le sommeil (2/3)


Idéal pour contrer des effets négatifs du stress, le CBD agit beaucoup sur l’humeur permettant d’être moins irritable, de ne plus ressentir cette impression d’être submergé ou dépassé, de se sentir libéré de certaines tensions, qu’elles soient physiques ou psychologiques et enfin de mieux dormir.

Rappelons que le cannabidiol vendu en France ne contient pas de THC (ou du moins sous le seuil 0,3 % comme le prévoit la législation) et qu’il n’a ni effet psychoactif, ni risque de dépendance quelconque.

Des études se penchent sur la question

Au cœur de nombreuses études scientifiques en cours, le CBD n’a pas encore révélé tous ses secrets. Même si on ne peut pas encore lui accorder des bienfaits définitifs, les recherches jusqu’à présent ont montré une certaine efficacité pour de nombreux consommateurs, ce qui explique en grande partie son succès dans les boutiques physiques comme sur les sites de commerce en ligne.

En 2021, l’étude nommée Radicle ACES (pour Advancing CBD Education and Science) initiée par Radicle Science avait pour but de déterminer les avantages thérapeutiques du CBD auprès de 3 000 participants. Cette étude a mis en lumière des améliorations cliniquement significatives sur 5 pans de la vie quotidienne : la qualité de vie, les douleurs sur le long terme, le bien-être général, l’anxiété ainsi que la qualité du sommeil. Et sur ce dernier point, 61 % des personnes interrogées ont constaté une évolution positive. Et pour la plupart, dès la première semaine d’expérimentation.

Une autre étude, menée cette fois par l’UFR des sciences pharmaceutiques de l’université de Bordeaux, a mis en évidence le potentiel thérapeutique du cannabidiol. On y apprend notamment que la sérotonine fait partie des neurotransmetteurs impliqués dans les états anxieux ainsi que le rythme du sommeil et le stress. Ce n’est pas pour rien si on l’appelle l’hormone du bonheur. La prise du CBD stimule justement la production de sérotonine !

FuturaSciences

16/10/2023

SANTE/MEDECINE - Le CBD et le sommeil - 1/3

Considéré comme une alternative naturelle aux solutions médicamenteuses contre les insomnies et les troubles du sommeil, le CBD poursuit son épopée comme en témoignent les nombreux avis sur Internet. Cette molécule aurait des propriétés bienfaitrices et représenterait une ressource pour les personnes qui souffrent de nuits non réparatrices.

Le potentiel du CBD est reconnu des scientifiques et apprécié des consommateurs. Le CBD peut être consommé sous des formes aussi diverses que variées : en e-liquide pour les cigarettes électroniques, en huile pour les applications cutanées, en gélules pour une prise quotidienne ou encore en fleurs pour l’incorporer dans vos recettes de cuisine favorites. Quelles que soient les méthodes d’assimilation, un spécialiste du CBD en France partage les multiples promesses de cette molécule. Entre autres : c’est un remède efficace contre le stress, l’anxiété et même les états dépressifs ;
on lui prête aussi des vertus antalgiques pour atténuer les douleurs chroniques et les courbatures ;
elle réduit l’inflammation, notamment sur le plan digestif et diminue les troubles gastro-intestinaux;
on lui attribue également des pouvoirs antioxydants qui participent au renforcement du système immunitaire.

FuturaSciences

ASTRONOMY - Eclipse Rings

 2023 October 16

An annular solar eclipse appears in the background with
the dark Moon appearing completely internal to the bright Sun.
In the foreground is a ridge with the silhouettes of two people, 
one standing, and one kneeling. 
Please see the explanation for more detailed information.

Eclipse Rings
Image Credit & Copyright: Jerry Zhang (left), Baolong Chen (photographer) & Amber Zhang (right)

Explanation: She knew everything but the question. She was well aware that there would be a complete annular eclipse of the Sun visible from their driving destination: Lake Abert in Oregon. She knew that the next ring-of-fire eclipse would occur in the USA only in 16 more years, making this a rare photographic opportunity. She was comfortable with the plan: that she and her boyfriend would appear in front of the eclipse in silhouette, sometimes alone, and sometimes together. She knew that the annular phase of this eclipse would last only a few minutes and she helped in the many hours of planning. She could see their friend who set up the camera about 400 meters away at the bottom of a ridge. What she didn't know was the question she would be asked. But she did know the answer: "yes".

15/10/2023

ASTRONOMY - Circular Sun Halo

 2023 October 14

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

Circular Sun Halo
Image Credit & Copyright: Vincenzo Mirabella

Explanation: Want to see a ring around the Sun? It's easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows. This one was captured by smart phone photography on May 29, 2021 near Rome, Italy. Carefully blocking the Sun, for example with a finger tip, is usually all that it takes to reveal the common bright halo ring. The halo's characteristic angular radius is about equal to the span of your hand, thumb to little finger, at the end of your outstretched arm. Want to see a ring of fire eclipse? That's harder. The spectacular annular phase of today's (October 14) solar eclipse, known as a ring of fire, is briefly visible only when standing along the Moon's narrow shadow track that passes over limited parts of North, Central, and South America. The solar eclipse is partial though, when seen from broader regions throughout the Americas.

ASTRONOMY - Christmas Tree Aurora

 2024 December 23 Christmas Tree Aurora Image Credit & Copyright:  Jingyi Zhang Explanation:  It was December and the sky lit up like a ...