Voici 10 des images les plus étonnantes captées par le télescope Hubble

  Le télescope spatial Hubble (HST), ou simplement Hubble, est un télescope spatial qui orbite en dehors de l’atmosphère terrestre, sur une orbite circulaire autour de notre planète à...
 

Le télescope spatial Hubble (HST), ou simplement Hubble, est un télescope spatial qui orbite en dehors de l’atmosphère terrestre, sur une orbite circulaire autour de notre planète à 593 km au-dessus du niveau de la mer, avec une période orbitale comprise entre 96 et 97 min.

Nommée en l’honneur de l’astronome Edwin Hubble, elle a été mise en orbite le 24 avril 1990 dans le cadre de la mission STS-31 et en tant que projet conjoint de la NASA et de l’Agence spatiale européenne inaugurant le programme des Grands Observatoires.

L’avantage d’avoir un télescope placé au-delà de la distorsion produite par l’atmosphère terrestre est que de cette façon, nous pouvons éliminer les effets de la turbulence atmosphérique, ce qui nous permet d’obtenir de meilleures images.

En outre, l’atmosphère absorbe fortement le rayonnement électromagnétique à certaines longueurs d’onde, en particulier dans l’infrarouge, ce qui diminue la qualité des images et rend impossible l’acquisition de spectres dans certaines bandes caractérisées par l’absorption de l’atmosphère terrestre.

Les télescopes terrestres sont également affectés par des facteurs météorologiques (présence de nuages) et la pollution lumineuse causée par les grands établissements urbains, ce qui réduit la fonctionnalité des télescopes terrestres.

Voici quelques faits sur Hubble :

Au moment de sa mise à l’eau, il avait la taille d’un bâtiment de quatre étages, 13 mètres de long et 4 mètres de diamètre, et pesant plus de 12 tonnes.

La caméra la plus sophistiquée du télescope spatial Hubble a créé une image en mosaïque d’un grand morceau de ciel, qui comprend au moins 10 000 galaxies.

Le Hubble est situé à 593 km au-dessus du niveau de la mer.

Avec le télescope spatial Hubble, environ un million d’objets ont été observés. En comparaison, l’œil humain ne peut voir qu’environ 6000 étoiles à l’œil nu.

Hubble orbite autour de la Terre à environ 28 000 km / h, tournant autour de notre planète environ toutes les 97 minutes.

Malgré la grande vitesse à laquelle la Terre tourne, le télescope est capable de pointer une étoile avec une grande précision (l’écart est inférieur à l’épaisseur d’un cheveu humain vu à une distance d’un kilomètre et demi).

La distance totale que le Hubble a parcourue autour de la Terre est d’environ 3 000 millions de kilomètres, ce qui est plus qu’un aller simple vers Neptune.

Des astronomes de plus de 45 pays ont publié des découvertes faites avec Hubble dans 4800 articles scientifiques.

Sans plus attendre, voici les images les plus fascinantes jamais prises par Hubble.

 

This Hubble image shows a spiral galaxy known as NGC 7331. First spotted by the prolific galaxy hunter William Herschel in 1784, NGC 7331 is located about 45 million light-years away in the constellation of Pegasus (the Winged Horse). Facing us partially edge-on, the galaxy showcases its beautiful arms, which swirl like a whirlpool around its bright central region. Astronomers took this image using Hubble’s Wide Field Camera 3, as they were observing an extraordinary exploding star — a supernova — near the galaxy’s central yellow core. Named SN 2014C, it rapidly evolved from a supernova containing very little hydrogen to one that is hydrogen-rich — in just one year. This rarely observed metamorphosis was luminous at high energies and provides unique insight into the poorly understood final phases of massive stars. NGC 7331 is similar in size, shape and mass to the Milky Way. It also has a comparable star formation rate, hosts a similar number of stars, has a central supermassive black hole and comparable spiral arms. The primary difference between this galaxy and our own is that NGC 7331 is an unbarred spiral galaxy — it lacks a “bar” of stars, gas and dust cutting through its nucleus, as we see in the Milky Way. Its central bulge also displays a quirky and unusual rotation pattern, spinning in the opposite direction to the galactic disk itself. By studying similar galaxies we hold a scientific mirror up to our own, allowing us to build a better understanding of our galactic environment, which we cannot always observe, and of galactic behavior and evolution as a whole. Credit: ESA/Hubble & NASA/D. Milisavljevic (Purdue University) #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #HubbleFriday #galaxy #pegasus #whirlpool #supernova #evolution

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

Hubble captured what looks like a colorful holiday ornament in space. It’s actually an image of NGC 6326, a planetary nebula with glowing wisps of outpouring gas that are lit up by a central star nearing the end of its life. When a star ages and the red giant phase of its life comes to an end, it starts to eject layers of gas from its surface leaving behind a hot and compact white dwarf. Sometimes this ejection results in elegantly symmetric patterns of glowing gas, but NGC 6326 is much less structured. This object is located in the constellation of Ara, the Altar, about 11,000 light-years from Earth. Planetary nebulae are one of the main ways in which elements heavier than hydrogen and helium are dispersed into space after their creation in the hearts of stars. Eventually some of this out-flung material may form new stars and planets. Credit: NASA/Hubble #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #nebula

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

#HubbleClassic These eerie, dark pillar-like structures are columns of cool interstellar hydrogen gas and dust that are also incubators for new stars. The towering pillars are about 5 light-years tall. Stars are being born deep inside the pillars, which are made of cold hydrogen gas laced with dust. The pillars are part of a small region of the Eagle Nebula, a vast star-forming region 6,500 light-years from Earth. The pillars are bathed in the blistering ultraviolet light from a grouping of young, massive stars located off the top of the image. Streamers of gas can be seen bleeding off the pillars as the intense radiation heats and evaporates it into space. Denser regions of the pillars are shadowing material beneath them from the powerful radiation. The dark, finger-like feature at bottom right may be a smaller version of the giant pillars. Credit: NASA/Hubble #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #nebula

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

#HubbleClassic Though the Cat’s Eye Nebula was one of the first planetary nebulae to be discovered, it is one of the most complex such nebulae ever seen. Planetary nebulae form when Sun-like stars gently eject their outer gaseous layers, creating amazing and confounding shapes. The Cat’s Eye Nebula, also known as NGC 6543, is a visual « fossil record » of the dynamics and late evolution of a dying star. It is estimated to be 1,000 years old. In 1994, initial Hubble observations revealed the nebula’s surprisingly intricate structures, including gas shells, jets of high-speed gas, and unusual shock-induced knots of gas. Subsequent Hubble images showed a bull’s-eye pattern of eleven or more concentric rings, or shells, of dust around the Cat’s Eye. Each « ring » is actually the edge of a spherical bubble seen projected onto the sky — that’s why it appears bright along its outer edge. Observations suggest the star that created the Cat’s Eye Nebula ejected its mass in a series of pulses at 1,500-year intervals. These convulsions created dust shells, each of which contains as much mass as all of the planets in our solar system combined (still only one percent of the Sun’s mass). These concentric shells make a layered, onion-skin structure around the dying star. The view from Hubble is like seeing an onion cut in half, where each skin layer is discernible. Credit: NASA/Hubble #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #nebula

 

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

#HubbleClassic This series of images shows an expanding halo of light around a distant star, named V838 Monocerotis. The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light 2 years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy. Called a light echo, the expanding illumination of a dusty cloud around the star has been revealing remarkable structures ever since the star suddenly brightened for several weeks in early 2002. Though Hubble has followed the light echo in several snapshots, this image shows swirls or eddies in the dusty cloud for the first time. These eddies are probably caused by turbulence in the dust and gas around the star as they slowly expand away. The dust and gas were likely ejected from the star in a previous explosion, similar to the 2002 event, which occurred some tens of thousands of years ago. The surrounding dust remained invisible and unsuspected until suddenly illuminated by the brilliant explosion of the central star. The Hubble telescope has imaged V838 Mon and its light echo several times since the star’s outburst in January 2002, in order to follow the constantly changing appearance of the dust as the pulse of illumination continues to expand away from the star at the speed of light. During the outburst event, the normally faint star suddenly brightened, becoming 600,000 times more luminous than our Sun. It was thus one of the brightest stars in the entire Milky Way, until it faded away again in April 2002. The star has some similarities to a class of objects called « novae, » which suddenly increase in brightness due to thermonuclear explosions at their surfaces; however, the detailed behavior of V838 Mon, in particular its extremely red color, has been completely different from any previously known nova. Credit: NASA/Hubble #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

 

Roughly 50 million light-years away lies a somewhat overlooked little galaxy named NGC 1559. Pictured here by Hubble’s Wide Field Camera 3, this barred spiral lies in the little-observed southern constellation of Reticulum (the Reticule). NGC 1559 has massive spiral arms chock-full of star formation, and is receding from us at a speed of about 808 miles per second (1,300 kilometers per second). The galaxy contains the mass of around ten billion suns — while this may sound like a lot, it is over 20 times less massive than the Milky Way. Although NGC 1559 appears in the sky near one of our closest galaxy neighbors, the Large Magellanic Cloud (LMC), this is just a trick of perspective. In reality, NGC 1559 is physically nowhere near the LMC in space — in fact, it truly is a loner, lacking the company of any nearby galaxies or membership of any galaxy cluster. Despite its lack of cosmic companions, when this lonely galaxy has a telescope pointed in its direction, it puts on quite a show. NGC 1559 has hosted a variety of spectacular exploding stars called supernovae, four of which we have observed — in 1984, 1986, 2005, and 2009. NGC 1559 may be alone in space, but we are watching and admiring from far away. Credit: ESA/Hubble & NASA #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #galaxy #spiral #HubbleFriday

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

This image of distant interacting galaxies, known collectively as Arp 142, bears an uncanny resemblance to a penguin guarding an egg. Data from NASA’s Spitzer and Hubble space telescopes have been combined to show these dramatic galaxies in light that spans the visible and infrared parts of the spectrum. This dramatic pairing shows two galaxies that couldn’t look more different as their mutual gravitational attraction slowly drags them closer together. The « penguin » part of the pair, NGC 2336, was probably once a relatively normal-looking spiral galaxy, flattened like a pancake with smoothly symmetric spiral arms. Rich with newly-formed hot stars, seen in visible light from Hubble as bluish filaments, its shape has now been twisted and distorted as it responds to the gravitational tugs of its neighbor. Strands of gas mixed with dust stand out as red filaments detected at longer wavelengths of infrared light seen by Spitzer. The « egg » of the pair, NGC 2937, by contrast, is nearly featureless. The distinctly different greenish glow of starlight tells the story of a population of much older stars. The absence of glowing red dust features informs us that it has long since lost its reservoir of gas and dust from which new stars can form. While this galaxy is certainly reacting to the presence of its neighbor, its smooth distribution of stars obscures any obvious distortions of its shape. Eventually these two galaxies will merge to form a single object, with their two populations of stars, gas and dust intermingling. This kind of merger was likely a significant step in the history of most large galaxies we see around us in the nearby universe, including our own Milky Way. At a distance of about 23 million light-years, these two galaxies are roughly 10 times farther away than our nearest major galactic neighbor, the Andromeda galaxy. The blue streak at the top of the image is an unrelated background galaxy that is farther away than Arp 142. Image credit: NASA-ESA/STScI/AURA/JPL-Caltech #NASA #Hubble #space #science #astronomy #universe #telescope #cosmos #animal #penguin #egg #galaxies

Une publication partagée par Hubble Space Telescope (@nasahubble) le

 

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