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28/09/2023

ASTRONOMY - The Deep Lagoon

 2023 September 28

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

The Deep Lagoon
Image Credit & Copyright: Josep DrudisChristian Sasse

Explanation: Ridges of glowing interstellar gas and dark dust clouds inhabit the turbulent, cosmic depths of the Lagoon Nebula. Also known as M8, The bright star forming region is about 5,000 light-years distant. It makes for a popular stop on telescopic tours of the constellation Sagittarius toward the center of our Milky Way Galaxy. Dominated by the telltale red emission of ionized hydrogen atoms recombining with stripped electrons, this deep telescopic view of the Lagoon's central reaches is about 40 light-years across. The bright hourglass shape near the center of the frame is gas ionized and sculpted by energetic radiation and extreme stellar winds from a massive young star.

27/09/2023

ASTRONOMY - STEVE and Milky Way Cross over Rural Road

 2023 September 27


A rural road is pictured running to the horizon with rural
grassy fields on both sides. Rising from the lower left is the
central band of our Milky Way Galaxy. Rising from the horizon
-- just at the visible end of the road, is a thin twisting band
of light twisting green and red bands -- a STEVE. The STEVE
crosses in front of the Milky Way band making a big

STEVE and Milky Way Cross over Rural Road
Image Credit & Copyright: Theresa Clarke

Explanation: Not every road ends in a STEVE. A week ago, a sky enthusiast's journey began with a goal: to photograph an aurora over Lake Huron. Driving through rural OntarioCanada, the forecasted sky show started unexpectedly early, causing the photographer to stop before arriving at the scenic Great Lake. Aurora images were taken toward the north -- but over land, not sea. While waiting for a second round of auroras, a peculiar band of light was noticed to the west. Slowly, the photographer and friends realized that this western band was likely an unusual type of aurora: a Strong Thermal Emission Velocity Enhancement (STEVE). Moreover, this STEVE was putting on quite a show: appearing intertwined with the central band of our Milky Way Galaxy while intersecting the horizon just near the end of the country road. After capturing this cosmic X on camera, the photographer paused to appreciate the unexpected awesomeness of finding extraordinary beauty in an ordinary setting.

26/09/2023

ASTRONOMY - A Ring of Fire Sunrise Solar Eclipse

 2023 September 24

A Ring of Fire Sunrise Solar Eclipse
Video Credit: Colin Legg & Geoff SimsMusic: Peter Nanasi

Explanation: What's rising above the horizon behind those clouds? It's the Sun. Most sunrises don't look like this, though, because most sunrises don't include the Moon. In the early morning of 2013 May 10, however, from Western Australia, the Moon was between the Earth and the rising Sun. At times, it would be hard for the uninformed to understand what was happening. In an annular eclipse, the Moon is too far from the Earth to block the entire Sun, and at most leaves a ring of fire where sunlight pours out around every edge of the Moon. The featured time-lapse video also recorded the eclipse through the high refraction of the Earth's atmosphere just above the horizon, making the unusual rising Sun and Moon appear also flattened. As the video continues, the Sun continues to rise, while the Sun and Moon begin to separate. The next annular solar eclipse will occur in less than three weeks. On Saturday, October 14, a ring of fire will be visible through clear skies from a thin swath crossing both North and South America.

25/09/2023

MUSICA -Julie Fuchs (Mozart) - Fra i pensier piu funesti

"Fra i pensier piu funesti"

AERONAUTIQUE - INVENTIONS QUI N'ONT JAMAIS VOLE - Les machines volantes : Charles Guillé et Thilorier

 

Cette image de nombreuses machines volantes a été conservée par la Library of Congress (la bibliothèque du Congrès, aux États-Unis). Elle date de 1885 environ. On peut y voir 45 projets, tous plus inventifs les uns que les autres, dont certains ont vraiment essayé de voler. C'est le cas du numéro 32 (en bas, au-dessus de la Tour Eiffel) qui illustre le planeur ballon dirigeable de Charles Guillé dont il s'est servi pour une ascension (ratée) à Paris le 13 novembre 1814. Le très innovant numéro 24 (à gauche sur l'image) représente la machine de Jean-Charles Thilorier, qui devait amener les troupes françaises en Angleterre dans le but de l'envahir. © Library of Congress

FuturaSciences

23/09/2023

ASTRONOMY - Afternoon Analemma

 2023 September 23

See Explanation.  Clicking on the picture will download
and animated gif.

Afternoon Analemma
Image Credit & Copyright: Ian Griffin (Otago Museum)

Explanation: An analemma is that figure-8 curve you get when you mark the position of the Sun at the same time each day for one year. To make this one, a 4x5 pinhole camera was set up looking north in southern New Zealand skies. The shutter was briefly opened each clear day in the afternoon at 4pm local time exposing the same photosensitized glass plate for the year spanning September 23, 2022 to September 19, 2023. On two days, the winter and summer solstices, the shutter was opened again 15 minutes after the main exposure and remained open until sunset to create the sun trails at the bottom and top of the curve. The equinox dates correspond to positions in the middle of the curve, not the crossover point. Of course, the curve itself is inverted compared to an analemma traced from the northern hemisphere. And while fall begins today at the Autumnal Equinox for the northern hemisphere, it's the Spring Equinox in the south.

22/09/2023

AERONAUTIQUE - LES INVENTIONS QUI N'ONT JAMAIS VOLE - Le Hughes H-4 Hercules d'Howard Hugues


Le Hughes H-4 Hercules d'Howard Hugues est un avion a demandé des moyens de conception à la hauteur de sa démesure (18 millions de dollars). Pendant son unique vol, il réussit à rester en l'air durant une minute à 21 mètres au-dessus de l'eau. Il a donc décollé, me direz-vous ! Pas tout à fait, son envol aurait eu lieu uniquement à cause de l'effet de sol. Cet échec cuisant le mit définitivement au garage.

FuturaSciences

ASTRONOMY - Cosmos in Reflection

 2023 September 21

See Explanation.  Clicking on the picture will download
and animated gif.

Cosmos in Reflection
Image Credit & Copyright: Jeff Dai (TWAN)

Explanation: During the day, over 12,000 large mirrors reflect sunlight at the 100-megawatt, molten-salt, solar thermal power plant at the western edge of the Gobi desert near Dunhuang, Gansu Province, China. Individual mirror panels turn to track the sun like sunflowers. They conspire to act as a single super mirror reflecting the sunlight toward a fixed position, the power station's central tower. During the night the mirrors stand motionless though. They reflect the light of the countless distant stars, clusters and nebulae of the Milky Way and beyond. This sci-fi night skyscape was created with a camera fixed to a tripod near the edge of the giant mirror matrix on September 15. The camera's combined sequence of digital exposures captures concentric arcs of celestial star trails through the night with star trails in surreal mirrored reflection.

21/09/2023

ASTRONOMY - Tagging Bennu

 2023 September 21

See Explanation.  Clicking on the picture will download
and animated gif.

Tagging Bennu
Image Credit: OSIRIS-RExUniversity of ArizonaNASAGoddard Scientific Visualization Studio

Explanation: The OSIRIS-REx spacecraft's arm reached out and touched asteroid 101955 Bennu on October 20, 2020, after a careful approach to the small, near-Earth asteroid's boulder-strewn surface. Dubbed a Touch-And-Go (TAG) sampling event, the 30 centimeter wide sampling head (TAGSAM) appears to crush some of the rocks in this close-up recorded by the spacecraft's SamCam. The image was snapped just after surface contact some 321 million kilometers from planet Earth. One second later, the spacecraft fired nitrogen gas from a bottle intended to blow a substantial amount of Bennu's regolith into the sampling head, collecting the loose surface material. And now, nearly three years later, on Sunday, September 24, that sample of asteroid Bennu is scheduled to arrive on planet Earth. The sample return capsule will be dropped off by the OSIRIS-Rex spacecraft as it makes a close flyby of Earth. Twenty minutes after the drop-off, the spacecraft will fire its thrusters to divert past Earth and continue on to orbit near-Earth asteroid 99942 Apophis.

20/09/2023

ASTRONOMY - Methane Discovered on Distant Exoplanet

 2023 September 20

An artist's illustration pictures a cloudy red planet
orbiting a distant red star. Near the exoplanet is a moon.
Please see the explanation for more detailed information.

Methane Discovered on Distant Exoplanet
Illustration Credit: Ahmad Jabakenji (ASU LebanonNorth Star Space Art); Data: NASAESACSAJWST

Explanation: Where else might life exist? One of humanity's great outstanding questions, locating planets where extrasolar life might survive took a step forward in 2019 with the discovery of a significant amount of water vapor in the atmosphere of distant exoplanet K2-18b. The planet and its parent star, K2-18, lie about 124 light years away toward the constellation of the Lion (Leo). The exoplanet is significantly larger and more massive than our Earth, but orbits in the habitable zone of its home star. K2-18, although more red than our Sun, shines in K2-18b's sky with a brightness similar to the Sun in Earth's sky. The 2019 discovery of atmospheric water was made in data from three space telescopes: HubbleSpitzer, and Kepler, by noting the absorption of water-vapor colors when the planet moved in front of the star. Now in 2023, further observations by the Webb Space Telescope in infrared light have uncovered evidence of other life-indicating molecules -- including methane. The featured illustration imagines exoplanet K2-18b on the far right orbited by a moon (center), which together orbit a red dwarf star depicted on the lower left.

ASTRONOMY - Fox Fur, Cone, and Christmas Tree

 2024 December 24 Fox Fur, Cone, and Christmas Tree Image Credit & Copyright:  Tim White Explanation:  What do the following things have...