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Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe

Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe
Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe Like photographers assembling a portfolio of best shots, astronomers have assembled a new, improved portrait of mankind's deepest-ever view of the universe. (Credit: NASA; ESA; G. Called the eXtreme Deep Field, or XDF, the photo was assembled by combining 10 years of NASA Hubble Space Telescope photographs taken of a patch of sky at the center of the original Hubble Ultra Deep Field. The Hubble Ultra Deep Field is an image of a small area of space in the constellation Fornax, created using Hubble Space Telescope data from 2003 and 2004. The new full-color XDF image is even more sensitive, and contains about 5,500 galaxies even within its smaller field of view. Magnificent spiral galaxies similar in shape to our Milky Way and the neighboring Andromeda galaxy appear in this image, as do the large, fuzzy red galaxies where the formation of new stars has ceased. Related Link Related:  Galaxies01.1. Horizontes Cósmicos - Cosmologia

Glowing Nebula's Clouds Look Like Giant Human Face in New Photo | NGC 3324, Nebulas & Star Formation | Space Photos & European Southern Observatory The wispy clouds of a distant nebula bursting with newborn stars take on an eerie face-like shape sculpted by stellar winds in a new photo snapped by a telescope in Chile. The hotbed of star birth, called NGC 3324, is full of hot young stars, whose ultraviolet radiation is making the gas clouds glow. The stellar wind and radiation from the newborn stars has also punched out a cavity in the surrounding gas and dust. The edge of the wall of gas and dust at the right in the photo resembles the profile of a human face, with a ridge in the center that looks like a nose. Astronomers often attach nicknames to nebulas based on their shape and their earthly likenesses. The new image was captured by the Wide Field Imager on the MPG/ESO 2.2-meter telescope at the European Southern Observatory's (ESO) La Silla Observatory in Chile's Atacama Desert. Strong stellar winds and intense ultraviolet radiation from these young stars have carved out a pocket in the nearby gas and dust.

Record : une galaxie 380 millions d'années après le Big Bang ? Un groupe d’astronomes a découvert 7 galaxies parmi les plus lointaines connues, observées sur une période s’étendant entre 350 et 600 millions d’années après le Big Bang . L’une d’entre elles pourrait même détenir un record. Hubble la montre peut-être alors que le cosmos n’avait que 380 millions d’années. Cela fait 9 ans que les astronomes étudient le Hubble Ultra Deep Field (HUDF). De 2003 à 2004, les instruments de Hubble ont observé pendant plusieurs heures, réparties sur une durée de 11 jours au total, une petite région de la voûte céleste située dans la constellation du Fourneau. Les astrophysiciens avaient ainsi obtenu une image dans le visible sur laquelle se trouvaient à la fois des galaxies proches et les plus anciennes connues à l’époque. Un groupe d’astronomes vient de publier un article sur arxiv portant sur des observations d’une partie du HUDF dans l’infrarouge proche pendant 6 semaines, d’août à septembre 2012. Le bilan de l' Hubble Ultra Deep Field 2012 est arrivé

The James Webb Space Telescope About Webb's Orbit The James Webb Space Telescope will observe primarily the infrared light from faint and very distant objects. But all objects, including telescopes, also emit infrared light. The L2 orbit is an elliptical orbit about the semi-stable second Lagrange point . In three of the solutions found by Lagrange, the bodies are in line (L1, L2, and L3); in the other two, the bodies are at the points of equilateral triangles (L4 and L5). In the case of Webb, the 3 bodies involved are the Sun, the Earth and the Webb. Other infrared missions have selected an L2 orbit, like WMAP and H2L2. Here are a few graphics that illustrate how far away Webb will be. (Note that these graphics are not to scale.) Astronomy Cast has a podcast on Lagrange points that you may find interesting.

File:Universe expansion2.png Ghostly gamma-ray beams blast from Milky Way's center (Phys.org) -- As galaxies go, our Milky Way is pretty quiet. Active galaxies have cores that glow brightly, powered by supermassive black holes swallowing material, and often spit twin jets in opposite directions. In contrast, the Milky Way's center shows little activity. But it wasn't always so peaceful. New evidence of ghostly gamma-ray beams suggests that the Milky Way's central black hole was much more active in the past. "These faint jets are a ghost or after-image of what existed a million years ago," said Meng Su, an astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA), and lead author of a new paper in the Astrophysical Journal. "They strengthen the case for an active galactic nucleus in the Milky Way's relatively recent past," he added. The two beams, or jets, were revealed by NASA's Fermi space telescope. The newfound jets may be related to mysterious gamma-ray bubbles that Fermi detected in 2010. The two structures also formed differently.

Explornova - Galaxies Description : Avant 1923, on croyait que l'univers se limitait à la Voie lactée, littéralement en grec la Galaxias ou Galaxie en français. Depuis les découvertes d’Edwin Hubble en 1929, de nombreux objets nébuleux sont devenus d’autres galaxies. Une galaxie est si grande qu’il nous faudrait des centaines de milliers d’années pour la traverser si nous pouvions voyager à la vitesse de la lumière, soit environ 300 000 km par seconde. Non seulement c’est extrêmement long, mais nous sommes aussi très loin d’atteindre une telle vitesse de voyage. Nous observons donc notre chère Voie Lactée depuis la Terre. Alors qu’il est difficile d’observer et de comprendre la forme de notre galaxie puisque nous sommes dedans, nous pouvons facilement observer d’autres galaxies dans l’Univers.

The James Webb Space Telescope File:Heic1401a-Abell2744-20140107.jpg Astronomers estimate 100 billion habitable Earth-like planets in the Milky Way, 50 sextillion in the universe Astronomers at the University of Auckland claim that there are actually around 100 billion habitable, Earth-like planets in the Milky Way — significantly more than the previous estimate of around 17 billion. There are roughly 500 billion galaxies in the universe, meaning there is somewhere in the region of 50,000,000,000,000,000,000,000 (5×1022) habitable planets. I’ll leave you to do the math on whether one of those 50 sextillion planets has the right conditions for nurturing alien life or not. The previous figure of 17 billion Earth-like planets in the Milky Way came from the Harvard-Smithsonian Center for Astrophysics in January, which analyzed data from the Kepler space observatory. Kepler essentially measures the dimming (apparent magnitude) of stars as planets transit in front of them — the more a star dims, the larger the planet. Gravitational microlensing, an effect theorized by Einstein back in 1936, is exactly what it sounds like.

Groupe local Un article de Wikipédia, l'encyclopédie libre. Voici une localisation des principales galaxies du Groupe local : Carte interactive du Groupe local. Cliquer sur les galaxies elles-mêmes — et non sur leur libellé — pour accéder à leur page. Historique[modifier | modifier le code] D'après l'historien des sciences américain Steven J. L'expression est reprise, dès 1936, par l’astronome américain Edwin Hubble, dans le chapitre VI de son ouvrage The Realm of Nebulae[8]. D'après Dick, c'est Baade qui utilisa, le premier, en 1944, l'expression « Groupe local de galaxies », dans une publication établissant l'appartenance au Groupe local de la galaxie irrégulière NGC 147 et de la galaxie naine sphéroïdale NGC 185[11]. Entre 1963 et 2000, la découverte de plusieurs galaxies naines fait passer le nombre à 38, avec un taux de découverte à peu près constant de quatre galaxies par décennie. Caractéristiques[modifier | modifier le code] Membres[modifier | modifier le code] Portail de l’astronomie

Observatory Astronomical observatories[edit] Ground-based observatories[edit] Ground-based observatories, located on the surface of Earth, are used to make observations in the radio and visible light portions of the electromagnetic spectrum. Most optical telescopes are housed within a dome or similar structure, to protect the delicate instruments from the elements. Telescope domes have a slit or other opening in the roof that can be opened during observing, and closed when the telescope is not in use. In most cases, the entire upper portion of the telescope dome can be rotated to allow the instrument to observe different sections of the night sky. For optical telescopes, most ground-based observatories are located far from major centers of population, to avoid the effects of light pollution. Radio observatories[edit] Beginning in 1930s, radio telescopes have been built for use in the field of radio astronomy to observe the Universe in the radio portion of the electromagnetic spectrum. See also[edit]

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