ASTRONOMY - Colorful Aurora over New Zealand

 2024 October 16

Colorful Aurora over New Zealand
Image Credit & Copyright: Tristian McDonald

Explanation: Sometimes the night sky is full of surprises. Take the sky over Lindis Pass, South Island, New Zealand one-night last week. Instead of a typically calm night sky filled with constant stars, a busy and dynamic night sky appeared. Suddenly visible were pervasive red aurora, green picket-fence aurora, a red SAR arc, a STEVE, a meteor, and the Moon. These outshone the center of our Milky Way Galaxy and both of its two satellite galaxies: the LMC and SMC. All of these were captured together on 28 exposures in five minutes, from which this panorama was composed. Auroras lit up many skies last week, as a Coronal Mass Ejection from the Sun unleashed a burst of particles toward our Earth that created colorful skies over latitudes usually too far from the Earth's poles to see them. More generally, night skies this month have other surprises, showing not only auroras -- but comets.

VILLES BIONIQUES DU FUTUR - L’arche bionique de Taiwan : la nature à la verticale

Dans le parc Gateway de Taichung, à Taiwan, cette tour est comme une forêt dans la ville. Des prairies et des jardins s'étalent en palier sur 390 m de hauteur dans un bâtiment autosuffisant, grâce aux énergies solaire et éolienne. On s'y promène pour apprécier la nature et pour trouver une vision panoramique sur la mégalopole. La tour sert aussi pour les relais de télécommunications.

© Vincent Callebaut

MUSIC - Strauss : Morgen (extrait de 4 Lieder) | Musica Sancta Ensemble

"Morgen"

LES NUAGES DIEUX DU CIEL - Qu'est-ce qu'un cirrus ?

Cirrus fibratus undulatus et cirrus fibratus, en Allemagne. Le cirrus est un nuage appartenant à l'étage supérieur (aux latitudes tempérées, sa base se situe entre 6.000 et 12.500 m de hauteur avec une épaisseur de l'ordre de 300 m). Il est constitué de bancs, de bandes ou de filaments séparés, blancs le plus souvent, qui revêtent un aspect fibreux ou un éclat soyeux (les deux apparences pouvant se conjuguer). Il n'est pas associé aux précipitations.

© Bernhard Mühr, Der Karlsruher Wolkenatlas, www.wolkenatlas.de

ASTRONOMY - Animation: Comet Tsuchinshan-ATLAS Tails Prediction

 2024 October 15

Animation: Comet Tsuchinshan-ATLAS Tails Prediction
Credit & Copyright: Nico Lefaudeux

Explanation: How bright and strange will the tails of Comet Tsuchinshan-ATLAS become? The comet has brightened dramatically over the few weeks as it passed its closest to the Sun and, just three days ago, passed its closest to the Earth. C/2023 A3 (Tsuchinshan–ATLAS) became of the brightest comets of the past century over the past few days, but was unfortunately hard to see because it was so nearly superposed on the Sun. As the comet appears to move away from the Sun, it is becoming a remarkable sight -- but may soon begin to fade. The featured animated video shows how the comet's tails have developed, as viewed from Earth, and gives one prediction about how they might further develop. As shown in the video, heavier parts of the dust tail that trails the comet have begun to appear to point in nearly the opposite direction from lighter parts of the dust tail as well as the comet's ion tail, the blue tail that is pushed directly out from the Sun by the solar wind.

INVENTIONS A L'HORIZON 2050 - Certaines plantes deviendront éternelles

Aujourd'hui, 70% des grandes cultures nécessitent de ressemer des graines chaque année : ce sont des plantes "annuelles". Or, selon les auteurs d'un article paru dans le magazine Science en juin 2010, les plantes vivaces (qui repoussent naturellement chaque année) nécessitent cinq fois moins d'eau et 35 fois moins d'engrais que les cultures classiques pour pousser.

Leur objectif est donc de transformer les semences classiques (le blé notamment) par transgénèse. "Ce serait la plus grande avancée de l'agriculture depuis 10 000 ans", s'enthousiasment les auteurs de l'article. Ils prévoient un aboutissement des recherches pour 2030.

JournalDuNet

ASTRONOMY - Comet Tsuchinshan-ATLAS Over the Lincoln Memorial

 2024 October 14

Comet Tsuchinshan-ATLAS Over the Lincoln Memorial
Credit & Copyright: Brennan Gilmore

Explanation: Go outside at sunset tonight and see a comet! C/2023 A3 (Tsuchinshan–ATLAS) has become visible in the early evening sky in northern locations to the unaided eye. To see the comet, look west through a sky with a low horizon. If the sky is clear and dark enough, you will not even need binoculars -- the faint tail of the comet should be visible just above the horizon for about an hour. Pictured, Comet Tsuchinshan-ATLAS was captured two nights ago over the Lincoln Memorial monument in Washington, DC, USA. With each passing day at sunset, the comet and its changing tail should be higher and higher in the sky, although exactly how bright and how long its tails will be can only be guessed.

ASTRONOMY - Aurora Timelapse Over Italian Alps

 2024 October 13

Aurora Timelapse Over Italian Alps
Video Credit & Copyright: Cristian Bigontina

Explanation: Did you see last night's aurora? This question was relevant around much of the world a few days ago because a powerful auroral storm became visible unusually far from the Earth's poles. The cause was a giant X-class solar flare on Tuesday that launched energetic electrons and protons into the Solar System, connecting to the Earth via our planet's magnetic field. A red glow of these particles striking oxygen atoms high in Earth's atmosphere pervades the frame, while vertical streaks dance. The featured video shows a one-hour timelapse as seen from Cortina d'Ampezzo over Alps Mountain peaks in northern Italy. Stars from our Milky Way Galaxy dot the background while streaks from airplanes and satellites punctuate the foreground. The high recent activity of our Sun is likely to continue to produce picturesque auroras over Earth during the next year or so.

LES NUAGES DIEUX DU CIEL - Stratocumulus au Nouveau-Mexique

Photo prise à Abique, au Nouveau-Mexique. Les stratocumulus sont constitués de gouttelettes d'eau, accompagnées parfois de gouttes de pluie ou de neige roulée et, plus rarement, de cristaux et de flocons de neige. S'il existe éventuellement des cristaux de glace, ils sont généralement trop clairsemés pour donner au nuage un aspect fibreux. Par temps extrêmement froid cependant, il arrive que les stratocumulus donnent naissance à d'abondantes virgæ de cristaux de glace, qui peuvent s'accompagner d'un halo.

© John Day, Cloudman's Gallery, www.cloudman.com,

ASTRONOMY - Northern Lights West Virginia

 

Northern Lights, West Virginia
Image Credit & Copyright: Jonathan Eggleston

Explanation: A gravel country lane gently winds through this colorful rural night skyscape. Captured from Monroe County in southern West Virginia on the evening of October 10, the starry sky above is a familiar sight. Shimmering curtains of aurora borealis or northern lights definitely do not make regular appearances here, though. Surprisingly vivid auroral displays were present on that night at very low latitudes around the globe, far from their usual northern and southern high latitude realms. The extensive auroral activity was evidence of a severe geomagnetic storm triggered by the impact of a coronal mass ejection (CME), an immense magnetized cloud of energetic plasma. The CME was launched toward Earth from the active Sun following a powerful X-class solar flare.