MUSIC - Maciej Tomasiewicz - Johannes Brahms - Hungarian Dances No. 5 & 6

"Hungarian Dances No. 5 & 6"

MACROPHOTOGRAPHIE - Miki Asai - Après le déluge une fourmi…

 

Une petite averse qui tombe sur votre jardin par un doux matin de printemps et c'est tout un monde qui est bouleversé. Pour la fourmi, la flaque qui mouille à peine vos chaussures représente tout un océan d'eau. Une question d'échelle. Et la Japonaise Miki Asai, passionnée de macrophotographie, l'a bien compris. Ce qui se passe à l'abri de nos regards est fascinant.

Alors selon vous, cette fourmi aventureuse parviendra-t-elle à rejoindre l'autre rive de ce détroit formé par la pluie ? Un galet après l'autre, c'est ainsi que l'insecte semble condamné à envisager son avenir. 

© Miki Asai

FuturaSciences

ASTRONOMIE - Ce soir une belle étreinte entre la Lune et Jupiter

Positions respectives de la planète Jupiter et de la Lune le 8 octobre 2022 vers 20h (heure de Paris). Le cercle bleu représente un champ de 6 degrés typique d’une paire de jumelles 10×50.

Alors que la nuit s’installe au soir du 8 octobre 2022, tournez-vous vers l’est et regardez le duo formé par la Lune et par Jupiter s’élever progressivement au-dessus de l’horizon. Vers 20h, les deux astres sont éloignés de moins de trois degrés l’un de l’autre, une distance qui permet de les admirer ensemble dans une paire de jumelles. La Lune est quasiment pleine, mais l’intense lumière qu’elle diffuse n’est pas suffisante pour masquer Jupiter. En effet, la planète géante est étincelante en ce moment, tout simplement parce qu’elle se trouve presque au plus près de la Terre (son opposition a eu lieu le 26 septembre 2022).

Ce lumineux tandem planétaire s’admire tout au long de la nuit du 8 au 9 octobre. Au petit matin, la Lune qui se déplace bien plus vite que Jupiter sur le fond de ciel aura déjà pris un peu ses distances (à un peu plus de quatre degrés). Ce sera elle qui passera la dernière sous l’horizon, vers 7h.

Stelvision

ASTRONOMY - Two Comets in Southern Skies

 2022 October 8

Two Comets in Southern Skies
Image Credit & Copyright: Jose J. Chambo (Cometografia)

Explanation: Heading for its closest approach to the Sun or perihelion on December 20, comet C/2017 K2 (PanSTARRS) remains a sight for telescopic observers as it sweeps through planet Earth's southern hemisphere skies. First time visitor from the remote Oort cloud this comet PanSTARRS sports a greenish coma and whitish dust tail about half a degree long at the upper left in a deep image from September 21. It also shares the starry field of view toward the constellation Scorpius with another comet, 73P/Schwassmann-Wachmann 3, seen about 1 degree below and right of PanSTARRS. Astronomers estimate that first time visitor comet C/2017 K2 (PanSTARRS) has been inbound from the Oort cloud for some 3 million years along a hyperbolic orbit. Schwassmann-Wachmann 3 is more familiar though. The periodic comet loops through its own elliptical orbit, from just beyond the orbit of Jupiter to the vicinity of Earth's orbit, once every 5.4 years. Just passing in the night, this comet PanSTARRS is about 20 light-minutes from Earth in the September 21 image. Seen to be disintegrating since 1995, Schwassmann-Wachmann 3 was about 7.8 light-minutes away.

ASTRONOMY - In Ganymede's Shadow

2022 October 7

In Ganymede's Shadow
Image Credit & Copyright: Andrew McCarthy

Explanation: At opposition, opposite the Sun in Earth's sky, late last month Jupiter is also approaching perihelion, the closest point to the Sun in its elliptical orbit, early next year. That makes Jupiter exceptionally close to our fair planet, currently resulting in excellent views of the Solar System's ruling gas giant. On September 27, this sharp image of Jupiter was recorded with a small telescope from a backyard in Florence, Arizona. The stacked video frames reveal the massive world bounded by planet girdling winds. Dark belts and light zones span the gas giant, along with rotating oval storms and its signature Great Red Spot. Galilean moon Ganymede is below and right in the frame. The Solar System's largest moon and its shadow are in transit across the southern Jovian cloud tops.

ASTRONOMY - NGC 4631: The Whale Galaxy

 2022 October 6

NGC 4631: The Whale Galaxy
Image Credit & Copyright: Michael Sherick

Explanation: NGC 4631 is a big beautiful spiral galaxy. Seen edge-on, it lies only 25 million light-years away in the well-trained northern constellation Canes Venatici. The galaxy's slightly distorted wedge shape suggests to some a cosmic herring and to others its popular moniker, The Whale Galaxy. Either way, it is similar in size to our own Milky Way. In this sharp color image, the galaxy's yellowish core, dark dust clouds, bright blue star clusters, and red star forming regions are easy to spot. A companion galaxy, the small elliptical NGC 4627 is just above the Whale Galaxy. Faint star streams seen in deep images are the remnants of small companion galaxies disrupted by repeated encounters with the Whale in the distant past. The Whale Galaxy is also known to have spouted a halo of hot gas glowing in X-rays.

ASTRONOMY - Expanding Plume from DART's Impact

2022 October 5

Expanding Plume from DART's Impact
Video Credit: Les Makes Observatory, J. Berthier, F. Vachier, A. Klotz, P. Thierry, T. Santana-Ros, ESA NEOCC, D. Föhring, E. Petrescu, M. Micheli

Explanation: What happens if you crash a spaceship into an asteroid? In the case of NASA's DART spaceship and the small asteroid Dimorphos, as happened last week, you get quite a plume. The goal of the planned impact was planetary protection -- to show that the path of an asteroid can be slightly altered, so that, if done right, a big space rock will miss the Earth. The high brightness of the plume, though, was unexpected by many, and what it means remains a topic of research. One possibility is that 170-meter wide Dimorphos is primarily a rubble pile asteroid and the collision dispersed some of the rubble in the pile. The featured time-lapse video covers about 20 minutes and was taken from the Les Makes Observatory on France's Reunion Island, off the southeast coast of southern Africa. One of many Earth-based observatories following the impact, the initial dot is primarily Dimorphos's larger companion: asteroid Didymos. Most recently, images show that the Didymos - Dimorphos system has developed comet-like tails.

ASTRONOMY - Star-Forming Eagle Nebula without Stars

 2022 October 4

Star-Forming Eagle Nebula without Stars
Image Credit & Copyright: Yannick Akar

Explanation: The whole thing looks like an eagle. A closer look at the Eagle Nebula's center, however, shows the bright region is actually a window into the center of a larger dark shell of dust. Through this window, a brightly-lit workshop appears where a whole open cluster of stars is being formed. In this cavity tall pillars and round globules of dark dust and cold molecular gas remain where stars are still forming. Paradoxically, it is perhaps easier to appreciate this impressive factory of star formation by seeing it without its stars -- which have been digitally removed in the featured image. The Eagle emission nebula, tagged M16, lies about 6500 light years away, spans about 20 light-years, and is visible with binoculars toward the constellation of the Serpent (Serpens). Creating this picture involved over 22 hours of imaging and combining colors emitted specifically by hydrogen (red), and oxygen (blue).

VOIE LACTEE SUR TERRE - Pologne/Slovaquie : les sommets du Kopa Kondracka dans les Tatras

Kopa Kondracka, situé sur la crête principale des Tatras occidentales est l'un des endroits les plus populaires. Il est constitué en partie de roches sédimentaires (calcaires et dolomites). Les pentes sont herbeuses et servaient pour les pâturages, avec une légère pente, avec un sommet en forme de dôme. Les phénomènes karstiques sont bien développés dans les calcaires. Dans le versant nord, il y a, entre autres la Grotte de Kondracka. Cette photo a été réalisée avec la technique « Time-blending » technique qui sera expliquée prochainement sur Futura.

Matériel utilisé : Sony a7 III + ZEISS 55mm f/1.8 | Fornax Mounts LighTrack ||

Photo de premier plan : f/11 90 sec ISO 400

Photo d'arrière plan : f/3.5 4 x 60 sec ISO 800

© Delil Geyik,

FuturaSciences

ASTRONOMY - Jupiter's Europa from Spacecraft Juno

 2022 October 3

Jupiter's Europa from Spacecraft Juno
Image Credit & License: NASA, JPL-Caltech, SwRI, MSSS; Processing: Andrea Luck

Explanation: What mysteries might be solved by peering into this crystal ball? In this case, the ball is actually a moon of Jupiter, the crystals are ice, and the moon is not only dirty but cracked beyond repair. Nevertheless, speculation is rampant that oceans exist under Europa's fractured ice-plains that could support life. Europa, roughly the size of Earth's Moon, is pictured here in an image taken a few days ago when the Jupiter-orbiting robotic spacecraft Juno passed within 325 kilometers of its streaked and shifting surface. Underground oceans are thought likely because Europa undergoes global flexing due to its changing gravitational attraction with Jupiter during its slightly elliptical orbit, and this flexing heats the interior. Studying Juno's close-up images may further humanity's understanding not only of Europa and the early Solar System but also of the possibility that life exists elsewhere in the universe.