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