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27/07/2022

ASTRONOMY - Crepuscular Moon Rays over Denmark

 2022 July 27

The featured image shows the Moon rising over water surrounded by
bright rays that peek through clouds. 
Please see the explanation for more detailed information.

Crepuscular Moon Rays over Denmark
Image Credit & Copyright: Ruslan Merzlyakov (astrorms)

Explanation: This moon made quite an entrance. Typically, a moonrise is quiet and serene. Taking a few minutes to fully peek above the horizon, Earth's largest orbital companion can remain relatively obscure until it rises high in the nighttime sky. About a week ago, however, and despite being only half lit by the Sun, this rising moon put on a show -- at least from this location. The reason was that, as seen from Limfjord in Nykøbing MorsDenmark, the moon rose below scattered clouds near the horizon. The result, captured here in a single exposure, was that moonlight poured through gaps in the clouds to created what are called crepuscular rays. These rays can fan out dramatically across the sky when starting near the horizon, and can even appear to converge on the other side of the sky. Well behind our Moon, stars from our Milky Way galaxy dot the background, and our galaxy's largest orbital companion -- the Andromeda galaxy -- can be found on the upper left.

26/07/2022

MICROPHOTOGRAPHIE - Une tête de fourmi psychédélique

 

Voilà à quoi ressemble une fourmi vue de très près. On peut apercevoir les deux antennes (en jaune), qui servent à de nombreuses fonctions sensorielles, comme l'odorat, le toucher et le goût. Elles sont tapissées de sensilles, des structures qui abritent des neurones sensoriels responsables de la détection des stimuli extérieurs. On peut également distinguer les mandibules (en orange), utilisées pour la mastication.

FuturaSciences

25/07/2022

ASTRONOMY - Find the new moon

 2022 July 25

The featured image shows an orange sky over water with 
a very faint, slight crescent Moon in the sky. 
Please see the explanation for more detailed information.

Find the New Moon
Image Credit & Copyright: Mohamad Soltanolkotabi

Explanation: Can you find the Moon? This usually simple task can be quite difficult. Even though the Moon is above your horizon half of the time, its phase can be anything from crescent to full. The featured image was taken in late May from Sant Martí d'EmpúriesSpain, over the Mediterranean Sea in the early morning. One reason you can't find this moon is because it is very near to its new phase, when very little of the half illuminated by the Sun is visible to the Earth. Another reason is because this moon is near the horizon and so seen through a long path of Earth's atmosphere -- a path which dims the already faint crescent. Any crescent moon is only visible near the direction the Sun, and so only locatable near sunrise of sunset. The Moon runs through all of its phases in a month (moon-th), and this month the thinnest sliver of a crescent -- a new moon -- will occur in three days.

23/07/2022

ASTRONOMY - Apollo 11 Landing Panorama

 2022 July 23

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

Apollo 11 Landing Panorama
Neil ArmstrongApollo 11NASA

Explanation: Have you seen a panorama from another world lately? Assembled from high-resolution scans of the original film frames, this one sweeps across the magnificent desolation of the Apollo 11 landing site on the Moon's Sea of Tranquility. The images were taken by Neil Armstrong looking out his window of the Eagle Lunar Module shortly after the July 20, 1969 landing. The frame at the far left (AS11-37-5449) is the first picture taken by a person on another world. Toward the south, thruster nozzles can be seen in the foreground on the left, while at the right, the shadow of the Eagle is visible to the west. For scale, the large, shallow crater on the right has a diameter of about 12 meters. Frames taken from the Lunar Module windows about an hour and a half after landing, before walking on the lunar surface, were intended to initially document the landing site in case an early departure was necessary.

21/07/2022

ASTRONOMY - Messier 10 and Comet

 2022 July 21

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

Messier 10 and Comet
Image Credit & CopyrightGerman Penelas Perez

Explanation: Imaged on July 15 2022, comet C/2017 K2 (PanSTARRS) had a Messier moment, sharing this wide telescopic field of view with globular star cluster Messier 10. Of course M10 was cataloged by 18th century comet hunter Charles Messier as the 10th object on his list of things that were definitely not comets. While M10 is about 14 thousand light-years distant, this comet PanSTARRS was about 15 light-minutes from our fair planet following its July 14 closest approach. Its greenish coma and dust tail entertaining 21st century comet watchers, C/2017 K2 is expected to remain a fine telescopic comet in northern summer skies. On a maiden voyage from our Solar System's remote Oort Cloud this comet PanSTARRS was discovered in May 2017 when it was beyond the orbit of Saturn. At the time that made it the most distant active inbound comet known. Its closest approach to the Sun will be within 1.8 astronomical units on December 19, beyond the orbital distance of Mars.

20/07/2022

ASTRONOMY - Pleiades over Half Dome

 2022 July 19

The featured image shows the bright blue Pleiades star cluster
behind Half Dome, a large circular rock formation that appears 
dark but with bright grooves.
Please see the explanation for more detailed information.

Pleiades over Half Dome
Image Credit & Copyright: Dheera Venkatraman

Explanation: Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years. Our Sun was likely born in a star cluster, but now, being about 4.5 billion years old, its stellar birth companions have long since dispersed. The Pleiades star cluster is pictured over Half Dome, a famous rock structure in Yosemite National Park in CaliforniaUSA. The featured image is a composite of 28 foreground exposures and 174 images of the stellar background, all taken from the same location and by the same camera on the same night in October 2019. After calculating the timing of a future juxtaposition of the Pleiades and Half Dome, the astrophotrographer was unexpectedly rewarded by an electrical blackout, making the background sky unusually dark.

18/07/2022

ASTRONOMIA - Sabe como soa um buraco negro no espaço? Assim

LE SON D'UN TROU NOIR (VOIR LINK)

Agora já pode conhecer um pouco mais do que se passa no Espaço: a NASA divulgou um áudio de 35 segundos que replica os sons que se ouvem dentro de um buraco negro.

O som é uma combinação de dados eletromagnéticos recolhidos do Perseus Galaxy Cluster – um aglomerado de galáxias na constelação de Perseu -, que fica a cerca de 240 milhões de anos-luz de distância.

A NASA, desde há dois anos, decidiu começar a traduzir as representações visuais do Espaço em algo que pudesse ser apreciado ao ouvido.

“Comecei os primeiros 10 anos da minha carreira a prestar uma maior atenção apenas ao visual, e percebi que havia uma falha para pessoas que não eram aprendizes visuais ou para pessoas cegas ou com pouca visão”, explicou a cientista visual Kimberly Arcand à NPR.

Em 2003, os astrónomos descobriram que as ondas emitidas pelo buraco negro causavam ondulações no gás quente do aglomerado, podendo, assim, traduzi-las para uma nota musical. A verdade é que nem sempre os buracos negros soam da mesma forma, dependendo da sua posição no centro das galáxias.

Um buraco negro é uma região com uma força da gravidade tão intensa, que atrai tudo à sua volta, inclusive a própria luz.

Visão

ASTRONOMY - Stephan's Quintet from Webb, Hubble, and Subaru

 2022 July 18

The featured image shows a grouping of four galaxies, some 
interacting, combining images from Webb, Hubble, and the Subaru telescope.
Please see the explanation for more detailed information.

Stephan's Quintet from Webb, Hubble, and Subaru
Image Credit: WebbHubbleSubaruNASAESACSANOAJSTScIProcessing & Copyright: Robert Gendler

Explanation: OK, but why can't you combine images from Webb and Hubble? You can, and today's featured image shows one impressive result. Although the recently launched James Webb Space Telescope (Webb) has a larger mirror than Hubble, it specializes in infrared light and can't see blue -- only up to about orange. Conversely, the Hubble Space Telescope (Hubble) has a smaller mirror than Webb and can't see as far into the infrared as Webb, but can image not only blue light but even ultraviolet. Therefore, Webb and Hubble data can be combined to create images across a wider variety of colors. The featured image of four galaxies from Stephan's Quintet shows Webb images as red and also includes images taken by Japan's ground-based Subaru telescope in Hawaii. Because image data for WebbHubble, and Subaru are made freely available, anyone around the world can process it themselves, and even create intriguing and scientifically useful multi-observatory montages.

17/07/2022

ASTRONOMY - Europa and Jupiter from Voyager 1

 2022 July 17

The featured image shows Jupiter's moon Europa in front
of Jupiter with many of Jupiter's clouds, including the Great
Red Spot, visible. 
Please see the explanation for more detailed information.

Europa and Jupiter from Voyager 1
Image Credit: NASAVoyager 1, JPL, CaltechProcessing & LicenseAlexis Tranchandon / Solaris

Explanation: What are those spots on Jupiter? Largest and furthest, just right of center, is the Great Red Spot -- a huge storm system that has been raging on Jupiter possibly since Giovanni Cassini's likely notation of it 357 years ago. It is not yet known why this Great Spot is red. The spot toward the lower left is one of Jupiter's largest moons: Europa. Images from Voyager in 1979 bolster the modern hypothesis that Europa has an underground ocean and is therefore a good place to look for extraterrestrial life. But what about the dark spot on the upper right? That is a shadow of another of Jupiter's large moons: Io. Voyager 1 discovered Io to be so volcanic that no impact craters could be found. Sixteen frames from Voyager 1's flyby of Jupiter in 1979 were recently reprocessed and merged to create the featured imageForty-five years ago this August, Voyager 1 launched from Earth and started one of the greatest explorations of the Solar System ever.

16/07/2022

ASTRONOMY - Tycho and Clavius at Dawn

 2022 July 16

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

Tycho and Clavius at Dawn
Image Credit & Copyright: Eduardo Schaberger Poupeau

Explanation: South is up in this dramatic telescopic view of the lunar terminator and the Moon's rugged southern highlands. The lunar landscape was captured on July 7 with the moon at its first quarter phase. The Sun shines at a low angle from the right as dawn comes to the region's young and old craters Tycho and Clavius. About 100 million years young, Tycho is the sharp-walled 85 kilometer diameter crater below and left of center. Its 2 kilometer tall central peak and far crater wall reflect bright sunlight, Its smooth floor lies in dark shadow. Debris ejected during the impact that created Tycho make it the stand out lunar crater when the Moon is near full though. They produce a highly visible radiating system of light streaks or rays that extend across much of the lunar near side. In fact, some of the material collected at the Apollo 17 landing site, about 2,000 kilometers away, likely originated from the Tycho impact. One of the oldest and largest craters on the Moon's near side, 225 kilometer diameter Clavius is due south (above) of Tycho. Clavius crater's own ray system resulting from its original impact event would have faded long ago. The old crater's worn walls and smooth floor are now overlayed by newer smaller craters from impacts that occurred after Clavius was formed. Reaching above the older crater, tops of the newer crater walls reflect this dawn's early light to create narrow shining arcs within a shadowed Clavius.

LES PLUS BEAUX ASTRES DE LA VOIE LACTéE - L’imposant maître Soleil

Sur cette image, on peut apercevoir les tailles des différentes planètes du Système solaire ainsi que du Soleil . Ou comment se sentir tout...