ASTRONOMY - LDN 43: The Cosmic Bat Nebula

 2022 October 31

LDN 43: The Cosmic Bat Nebula
Image Credit & Copyright: Mark Hanson and Mike Selby; Text: Michelle Thaller (NASA's GSFC)

Explanation: What is the most spook-tacular nebula in the galaxy? One contender is LDN 43, which bears an astonishing resemblance to a vast cosmic bat flying amongst the stars on a dark Halloween night. Located about 1400 light years away in the constellation Ophiuchus, this molecular cloud is dense enough to block light not only from background stars, but from wisps of gas lit up by the nearby reflection nebula LBN 7. Far from being a harbinger of death, this 12-light year-long filament of gas and dust is actually a stellar nursery. Glowing with eerie light, the bat is lit up from inside by dense gaseous knots that have just formed young stars.

ASTRONOMY - Seven Years of Halley Dust

 2022 October 28

Seven Years of Halley Dust
Image Credit & Copyright: Petr Horalek / Institute of Physics in Opava

Explanation: History's first known periodic comet Halley (1P/Halley) returns to the inner Solar System every 75 years or so. The famous comet made its last appearance to the naked-eye in 1986. But dusty debris from Comet Halley can be seen raining through planet Earth's skies twice a year during two annual meteor showers, the Eta Aquarids in May and the Orionids in October. Including meteors near the shower maximum on October 21, this composite view compiles Orionid meteors captured from years 2015 through 2022. About 47 bright meteors are registered in the panoramic night skyscape. Against a starry background extending along the Milky Way, the Orionid meteors all seem to radiate from a point just north of Betelgeuse in the familiar constellation of the Hunter. In the foreground are mountains in eastern Slovakia near the city of Presov.

ASTRONOMIE - Comprendre Mars

La planète rouge est considérée par certains experts comme une solution potentielle à la survie de l'humanité. Mais connaissez-vous réellement cette planète ?

ASTRONOMY - Sunset, Moonset, Taj Mahal

 2022 October 27

Sunset, Moonset, Taj Mahal
Image Credit & Copyright: Neelam and Ajay Talwar (TWAN)

Explanation: On October 25th, Sun and New Moon set together as seen from Agra, India. Their close conjunction near the western horizon, a partial solar eclipse, was captured in this elevated view in hazy skies near the solitary dome of the Taj Mahal. Of course, the partial solar eclipse was also seen from most of Europe, northern Africa, the Middle East, and western parts of Asia. This eclipse was the last of two solar eclipses (both partial eclipses) in 2022. But the next Full Moon will slide through planet Earth's shadow on November 7/8, in a total lunar eclipse.

MICROPHOTOGRAPHIE - Granulite et graphite

 

Granulite comportant du graphite. La granulite est une roche métamorphique composée de quartz et de feldspath. L'échantillon provient de l'État de Kerala, au sud ouest de l'Inde. Image réalisée en lumière polarisée. Grossissement 2,5x.

Dr. Bernardo Cesare

Département de géosciences, Padoue, Italie

FuturaSciences

MACROPHOTOGRAPHIE - Miki Asai - En attendant que vienne une fourmi

La photographe japonaise Miki Asai a choisi la macrophotographie pour révéler à nos yeux ce que la nature a l'habitude de nous dissimuler avec pudeur. Ainsi, elle se refuse à manipuler les insectes qu'elle prend pour modèles. Au lieu de cela, elle prône la patience. Elle peut parfois attendre ainsi plusieurs heures que la scène parfaite se dessine sous son objectif.

FuturaSciences

AVIATION IMAGINEE - La voiture volante individuelle

Hildebrands, une célèbre marque de chocolat allemand dans les années 1900, nous imaginait chacun en possession d'une voiture volante. Ces dessins suggèrent différents types d'appareils, allant des ailes de chauve-souris à la baignoire surmontant quatre ailes improbables. Ils nous font aujourd'hui sourire par leur optimisme mais sont surtout révélateurs de l'époque des pionniers de l'aviation qui laissait présager un futur aérien...

© Hildebrands

FuturaSciences

ASTRONOMIE - Mars arrive !

Bien visible à l’œil nu, Mars est sans doute le monde planétaire qui excite le plus notre imaginaire. Observable tous les deux ans, elle est au plus près de nous le 8 décembre 2022 et s’observe facilement tout le long de l’automne 2022 et de l’hiver 2023

Stelvision

ASTRONOMY - Jupiter Rotates as Moons Orbit

 2022 October 25

Jupiter Rotates as Moons Orbit
Video Credit & Copyright: Makrem Larnaout

Explanation: Jupiter and its moons move like our Sun and its planets. Similarly, Jupiter spins while its moons circle around. Jupiter’s rotation can be observed by tracking circulating dark belts and light zones. The Great Red Spot, the largest storm known, rotates to become visible after about 15 seconds in the 48-second time lapse video. The video is a compilation of shorts taken over several nights last month and combined into a digital recreation of how 24-continuous hours would appear. Jupiter's brightest moons always orbit in the plane of the planet's rotation, even as Earth’s spin makes the whole system appear to tilt. The moons Europa, Ganymede, and Io are all visible, with Europa's shadow appearing as the icy Galilean moon crosses Jupiter's disk. Jupiter remains near opposition this month, meaning that it is unusually bright, near to its closest to the Earth, and visible nearly all night long.

ASTRONOMY - Milky Way and Zodiacal Light over Australian Pinnacles

 2022 October 23

Milky Way and Zodiacal Light over Australian Pinnacles
Image Credit & Copyright: Jingyi Zhang

Explanation: What strange world is this? Earth. In the foreground of the featured image are the Pinnacles, unusual rock spires in Nambung National Park in Western Australia. Made of ancient sea shells (limestone), how these human-sized picturesque spires formed remains a topic of research. The picturesque panorama was taken in 2017 September. A ray of zodiacal light, sunlight reflected by dust grains orbiting between the planets in the Solar System, rises from the horizon near the image center. Arching across the top is the central band of our Milky Way Galaxy. The planets Jupiter and Saturn, as well as several famous stars are also visible in the background night sky.

ASTRONOMY - Pillars of Creation

 2022 October 20

Pillars of Creation
Image Credit: Science - NASA, ESA, CSA, STScI, NIRCam
Processing - Joseph DePasquale (STScI), Anton M. Koekemoer (STScI), Alyssa Pagan (STScI)

Explanation: A now famous picture from the Hubble Space Telescope featured these star forming columns of cold gas and dust light-years long inside M16, the Eagle Nebula, dubbed the Pillars of Creation. This James Webb Space Telescope NIRCam image expands Hubble's exploration of that region in greater detail and depth inside the iconic stellar nursery. Particularly stunning in Webb's near infrared view is the telltale reddish emission from knots of material undergoing gravitational collapse to form stars within the natal clouds. The Eagle Nebula is some 6,500 light-years distant. The larger bright emission nebula is itself an easy target for binoculars or small telescopes. M16 lies along the plane of our Milky Way galaxy in a nebula rich part of the sky, toward the split constellation Serpens Cauda (the tail of the snake).

MERVEILLEUX MONDE SOUS-MARIN - La baleine à bosse - Megaptera novaeangliae

Polynésie française - Océan Pacifique - Archipel des Australes - Ile de Rurutu

Par jeu, sous le coup de l'énervement ou pour intimider un amoureux trop pressant, les baleines frappent la surface de l'eau de leur queue à la puissance phénoménale. Les motifs, les taches, les échancrures qui marquent la face interne de la caudale varient d'un individu à l'autre, et sont une sorte de carte d'identité de l'animal.

D'une année sur l'autre, les guides animaliers parviennent ainsi à reconnaître mères et petits, et à évaluer la bonne santé de la population locale de cétacés. Dans certaines régions, les cétologues dressent de véritables catalogues d'identification. La population mondiale des baleines à bosse est actuellement estimée à vingt mille individus.

© Alexis Rosenfeld

FuturaSciences

ASTRONOMY - A Galaxy Beyond Stars, Gas, Dust

 2022 October 19

A Galaxy Beyond Stars, Gas, Dust
Image Credit & Copyright: Howard Trottier; Text: Emily Rice

Explanation: Do we dare believe our eyes? When we look at images of space, we often wonder whether they are "real", and just as often the best answer varies. In this case, the scene appears much as our eyes would see it, because it was obtained using RGB (Red, Green, Blue) filters like the cone cells in our eyes, except collecting light for 19 hours, not a fraction of a second. The featured image was captured over six nights, using a 24-inch diameter telescope in the Sierra Nevada Mountains, in California, USA. The bright spiral galaxy at the center (NGC 7497) looks like it is being grasped by an eerie tendril of a space ghost, and therein lies the trick. The galaxy is actually 59 million light years away, while the nebulosity is MBM 54, less than one thousand light years away, making it one of the nearest cool clouds of gas and dust -- galactic cirrus -- within our own Milky Way Galaxy. Both are in the constellation of Pegasus, which can be seen high overhead from northern latitudes in the autumn.

AVIATION IMAGINEE - Des ballons gonflables pour marcher sur l'eau

 

Dans les années 1900, une célèbre marque de chocolat leader sur son marché, Hildebrands, agrémentait ses tablettes de cartes postales imaginant l'an 2000. Celle-ci illustre la croyance selon laquelle, à l'aide de ballons gonflables, nous pourrions nous balader en marchant sur l'eau. Vous remarquerez les très pratiques petites chaussures-péniches en bois pour éviter de mouiller ses souliers.

© Hildebrands

ASTRONOMY - Milky Way Auroral Flower

 2022 October 18

Milky Way Auroral Flower
Image Credit & Copyright: Göran Strand

Explanation: Could the stem of our Milky Way bloom into an auroral flower? No, not really, even though it may appear that way in today’s featured all-sky image. On the left, the central plane of our home galaxy extends from the horizon past the middle of the sky. On the right, an auroral oval also extends from the sky's center -- but is dominated by bright green-glowing oxygen. The two are not physically connected, because the aurora is relatively nearby, with the higher red parts occurring in Earth's atmosphere only about 1000 kilometers high. In contrast, an average distance to the stars and nebulas we see in the Milky Way more like 1000 light-years away - 10 trillion times further. The featured image composite was taken in early October across a small lake in Abisko, northern Sweden. As our Sun's magnetic field evolves into the active part of its 11-year cycle, auroras near both of Earth's poles are sure to become more frequent.

MACROPHOTOGRAPHIE - Miki Asai -Lorsque deux mondes se rejoignent

« Lorsque j'ai acheté mon premier objectif macro, j'ai regardé à travers mon viseur et j'ai remarqué qu'il y avait là, dans mon jardin, des gouttes de pluie et des fourmis », aime à raconter la photographe japonaise Miki Asai. D'autres en seraient restés là. Elle a cherché à rendre ce monde invisible à nos yeux, encore plus joli qu'il ne l'est naturellement.

Ici, sur une montagne de pétales, une fourmi en quête d'eau. Et dans la gouttelette élégamment déposée là par la photographe au sommet de la montagne, le reflet singulier de sa voiture et de sa maison. L'instant merveilleux où deux mondes se touchent presque du doigt.

© Miki Asai

FuturaSciences

ASTRONOMY - Barred Spiral Galaxy NGC 1300

 2022 October 16

Barred Spiral Galaxy NGC 1300
Image Credit: NASA ESA, Hubble Heritage

Explanation: Across the center of this spiral galaxy is a bar. And at the center of this bar is smaller spiral. And at the center of that spiral is a supermassive black hole.  This all happens in the big, beautiful, barred spiral galaxy cataloged as NGC 1300, a galaxy that lies some 70 million light-years away toward the constellation of the river Eridanus. This Hubble Space Telescope composite view of the gorgeous island universe is one of the most detailed Hubble images ever made of a complete galaxy. NGC 1300 spans over 100,000 light-years and the Hubble image reveals striking details of the galaxy's dominant central bar and majestic spiral arms. How the giant bar formed, how it remains, and how it affects star formation remains an active topic of research.

ASTRONOMY - GRB 221009A

 2022 October 15

GRB 221009A
Image Credit: NASA, DOE, Fermi LAT Collaboration

Explanation: Gamma-ray burst GRB 221009A likely signals the birth of a new black hole, formed at the core of a collapsing star long ago in the distant universe. The extremely powerful blast is depicted in this animated gif constructed using data from the Fermi Gamma Ray Space Telescope. Fermi captured the data at gamma-ray energies, detecting photons with over 100 million electron volts. In comparison visible light photons have energies of about 2 electron volts. A steady, high energy gamma-ray glow from the plane of our Milky Way galaxy runs diagonally through the 20 degree wide frame at the left, while the transient gamma-ray flash from GRB 221009A appears at center and then fades. One of the brightest gamma-ray bursts ever detected GRB 221009A is also close as far as gamma-ray bursts go, but still lies about 2 billion light-years away. In low Earth orbit Fermi’s Large Area Telescope recorded gamma-ray photons from the burst for more than 10 hours as high-energy radiation from GRB 221009A swept over planet Earth last Sunday, October 9.

ASTRONOMY - Dust Shells around WR 140 from Webb

 2022 October 13

Dust Shells around WR 140 from Webb
Image Credit: NASA, ESA, CSA, JWST, MIRI, ERS Program 1349; Processing: Judy Schmidt

Explanation: What are those strange rings? Rich in dust, the rings are likely 3D shells -- but how they were created remains a topic of research. Where they were created is well known: in a binary star system that lies about 6,000 light years away toward the constellation of the Swan (Cygnus) -- a system dominated by the Wolf-Rayet star WR 140. Wolf-Rayet stars are massive, bright, and known for their tumultuous winds. They are also known for creating and dispersing heavy elements such as carbon which is a building block of interstellar dust. The other star in the binary is also bright and massive -- but not as active. The two great stars joust in an oblong orbit as they approach each other about every eight years. When at closest approach, the X-ray emission from the system increases, as, apparently, does the dust expelled into space -- creating another shell. The featured infrared image by the new Webb Space Telescope resolves greater details and more dust shells than ever before.

AVIATION IMAGINEE - La montgolfière familiale

 

Dans les années 1900, certaines personnes avaient imaginé des engins volants de différentes tailles (un peu comme le principe des voitures berlines familiales d'aujourd'hui) largement calqués sur les montgolfières. En effet, un peu plus d'un siècle plus tôt, les frères Montgolfier (Joseph-Michel et Jacques-Étienne) avaient fait voler le premier ballon gonflé d'air chaud. Dans l'imaginaire populaire, le ballon était donc l'une des seules formes d'objets volants connues.

© Hildebrands

FuturaSciences

ASTRONOMY - Ou4: The Giant Squid Nebula

 2022 October 12

Ou4: The Giant Squid Nebula
Image Credit & Copyright: Tommy Lease

Explanation: A mysterious squid-like cosmic cloud, this nebula is very faint, but also very large in planet Earth's sky. In the image, composed with 30 hours of narrowband image data, it spans nearly three full moons toward the royal constellation Cepheus. Discovered in 2011 by French astro-imager Nicolas Outters, the Squid Nebula's bipolar shape is distinguished here by the telltale blue-green emission from doubly ionized oxygen atoms. Though apparently surrounded by the reddish hydrogen emission region Sh2-129, the true distance and nature of the Squid Nebula have been difficult to determine. Still, a more recent investigation suggests Ou4 really does lie within Sh2-129 some 2,300 light-years away. Consistent with that scenario, the cosmic squid would represent a spectacular outflow of material driven by a triple system of hot, massive stars, cataloged as HR8119, seen near the center of the nebula. If so, this truly giant squid nebula would physically be over 50 light-years across.

ASTRONOMY - Stars, Dust, Pillars, and Jets in the Pelican Nebula

 2022 October 11

Stars, Dust, Pillars, and Jets in the Pelican Nebula
Image Credit & Copyright: Adriano Almeida

Explanation: What dark structures arise within the Pelican Nebula? On the whole, the nebula appears like a bird (a pelican) and is seen toward the constellation of a different bird: Cygnus, a Swan. But inside, the Pelican Nebula is a place lit up by new stars and befouled by dark dust. Smoke-sized dust grains start as simple carbon compounds formed in the cool atmospheres of young stars but are dispersed by stellar winds and explosions. Two impressive Herbig-Haro jets are seen emitted by the star HH 555 on the right, and these jets are helping to destroy the light year-long dust pillar that contains it. Other pillars and jets are also visible. The featured image was scientifically-colored to emphasize light emitted by small amounts of heavy elements in a nebula made predominantly of the light elements hydrogen and helium. The Pelican Nebula (IC 5067 and IC 5070) is about 2,000 light-years away and can be found with a small telescope to the northeast of the bright star Deneb.

ASTRONOMY - A Double Lunar Analemma over Turkey

 2022 October 10

A Double Lunar Analemma over Turkey
Image Credit & Copyright: Betul Turksoy

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. But the trick to imaging an analemma of the Moon is to wait bit longer. On average the Moon returns to the same position in the sky about 50 minutes and 29 seconds later each day. So photograph the Moon 50 minutes 29 seconds later on successive days. Over one lunation or lunar month it will trace out an analemma-like curve as the Moon's actual position wanders due to its tilted and elliptical orbit. Since the featured image was taken over two months, it actually shows a double lunar analemma. Crescent lunar phases too thin and faint to capture around the New moon are missing. The two months the persistent astrophotographer chose were during a good stretch of weather during July and August, and the location was Kayseri, Turkey

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.

ASTRONOMY - Supernova Cannon Expels Pulsar J0002

 2022 October 2

Supernova Cannon Expels Pulsar J0002
Image Credit: F. Schinzel et al. (NRAO, NSF), Canadian Galactic Plane Survey (DRAO), NASA (IRAS);
Composition: Jayanne English (U. Manitoba)

Explanation: What could shoot out a neutron star like a cannon ball? A supernova. About 10,000 years ago, the supernova that created the nebular remnant CTB 1 not only destroyed a massive star but blasted its newly formed neutron star core -- a pulsar -- out into the Milky Way Galaxy. The pulsar, spinning 8.7 times a second, was discovered using downloadable software Einstein@Home searching through data taken by NASA's orbiting Fermi Gamma-Ray Observatory. Traveling over 1,000 kilometers per second, the pulsar PSR J0002+6216 (J0002 for short) has already left the supernova remnant CTB 1, and is even fast enough to leave our Galaxy. Pictured, the trail of the pulsar is visible extending to the lower left of the supernova remnant. The featured image is a combination of radio images from the VLA and DRAO radio observatories, as well as data archived from NASA's orbiting IRAS infrared observatory. It is well known that supernovas can act as cannons, and even that pulsars can act as cannonballs -- what is not known is how supernovas do it.

ENERGIE - 100 millions de degrés. Plus chaud que le soleil

C’est dans le réacteur KSTAR (Korea Superconducting Tokamak Advanced Research) que les scientifiques sud-coréens sont parvenus à créer un soleil artificiel. Le réacteur est en effet capable d’atteindre des températures extrêmes dépassant les 100 millions de degrés pendant 30 secondes.

Le site Wion, qui rapporte la nouvelle, précise que, à titre de comparaison, « le noyau du soleil atteint des températures d'environ 15 millions de degrés ». C’est la fusion nucléaire qui alimente notre Soleil en fusionnant des noyaux atomiques, ce qui est à l’origine des quantités d’énergie créée.

Wion indique par ailleurs que le procédé utilisé par les astrophysiciens sud-coréens est l’opposé du processus de fission utilisé par les centrales nucléaires ainsi que des armes atomiques.

« Nous disons généralement que l'énergie de fusion est une source d'énergie de rêve - elle est presque illimitée, avec de faibles émissions de gaz à effet de serre et aucun déchet hautement radioactif - [mais la dernière percée] signifie que la fusion n'est pas un rêve », explique Yoo Suk- jae, le président de l’Institut coréen de l'énergie de fusion.

Un rêve qui pourrait peut-être permettre de lutter contre le réchauffement climatique et la crise énergétique. Ce processus de fusion n’émet pas de gaz à effet de serre et comporterait moins de risques, renseignent les scientifiques.

Cette source artificielle d’énergie nucléaire doit permettre de répondre aux problèmes que posent les ressources naturelles en énergie. Elle pourrait conduire à une production d’énergie propre qui génère moins de pollution que la fission nucléaire.

Démotivateur

MACROPHOTOGRAPHIE - Une fleur qui laisse son empreinte

 

Pour réaliser ce cliché troublant d'émotions, la photographe japonaise Miki Asai a simplement déposé quelques gouttes d'eau sur un plateau noir. La scène est ensuite mise en lumière depuis l'arrière par un éclairage LED. Comme une touche de technologie pour rendre service à l'imagination d'une amoureuse de la nature.

Pour vous laisser totalement embarquer dans le rêve, envisagez, un instant seulement, que ces gouttelettes sont les empreintes laissées derrière cette fleur aux allures virginales sur le chemin de la vie. 

© Miki Asai

FuturaSciences

PHOTOGRAPHIE SOUS-MARINE - Nurserie de requins-citron

Le requin-citron, qui doit son nom à sa couleur entre le gris et le jaune pâle, vit dans les zones tropicales de l'Atlantique et du Pacifique. Les mangroves des Bahamas constituent une véritable nurserie pour cette espèce, où les jeunes individus passent les 5 à 8 premières années de leur vie.

© ANITA KAINRATH, UPY 2020

FuturaSciences

ASTRONOMY - Lunation Matrix

 2022 October 1

Lunation Matrix
Image Credit & Copyright: Tunc Tezel (TWAN)

Explanation: Observe the Moon every night and you'll see its visible sunlit portion gradually change. In phases progressing from New Moon to Full Moon to New Moon again, a lunar cycle or lunation is completed in about 29.5 days. Top left to bottom right, this 7x4 matrix of telescopic images captures the range of lunar phases for 28 consecutive nights, from the evening of July 29 to the morning of August 26, following an almost complete lunation. No image was taken 24 hours or so just after and just before New Moon, when the lunar phase is at best a narrow crescent, close to the Sun and really hard to see. Finding mostly clear Mediterranean skies required an occasional road trip to complete this lunar cycle project, imaging in early evening for the first half and late evening and early morning for the second half of the lunation. Since all the images are registered at the same scale you can use this matrix to track the change in the Moon's apparent size during the single lunation. For extra credit, find the lunar phase that occurred closest to perigee.