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Hubble Views Grand Star-Forming Region

Hubble Views Grand Star-Forming Region
Related:  étoiles

How red giants lose weight An artist's impression of a star and dust shell. Image: Anna Mayall Putting all dieters to shame, the red giant stars of our galaxy lose many times the entire mass of the Earth, every year. Unlike Hollywood starlets, they have not previously revealed their weight-loss secrets, posing an enigma for scientists, until this breakthrough study by the University of Sydney, published in Nature on 12 April. The solution of the mass loss problem has profound implications across astronomy and beyond. "The winds that stream from the upper atmosphere of the red giant stars are responsible for removing massive amounts of matter," said lead author Barnaby Norris, a PhD student from the University's Faculty of Science. Using a state-of-the-art telescope at one of the world's leading observatories in Northern Chile, the research team created images of the faint starlight glinting off an unexpected halo of dust grains around the red stars. Editor's Note: Original news release can be found here.

The Very Curious Creation of an Ageing Star The NASA/ESA Hubble Space Telescope has made a rare celestial catch. Close to a bright, nearby star in this image, the bizarre, whorl-shaped object known as IRAS 22036+5306 has been captured during a brief tumultuous period late in a star's life. Inside IRAS 22036+5306 lies an aged star that has coughed off almost all of its outer material, forming a cloud in space. Hidden under this veil, the dense, still-burning, exposed core of the star grows hotter. Encircling the star is a torus consisting partly of castoff material, as well as possibly the grainy remnants of comets and other small, rocky bodies. IRAS 22036+5306 is making the transition through the protoplanetary, or preplanetary, nebula phase. Planetary nebulae are much longer-lived than their precursors, protoplanetary nebulae, and are therefore more commonly spotted. IRAS 22036+5306 is found about 6500 light-years away in the constellation of Cepheus (The King). Credit:

Saturn's Largest Moon Seen in Unprecedented Detail | Wired Science Titan is one of the solar system’s coldest places, but that hasn’t stopped Saturn’s largest moon from being incredibly dynamic.A collection of 13 new studies about Titan show previously undetected craters and river deltas, and provide improved maps of its surface and interior.They also reveal new details about the moon’s mysterious 29.5-Earth-year-long seasonal cycle (the equivalent of one year on Saturn, which orbits the sun at a distance of 890 million miles).“We’re really starting to see quite a lot of profound changes on Titan,” said planetary scientist Ralph Lorenz at Johns Hopkins University’s Applied Physics Laboratory. “We’re learning things now that you could only learn after years of repeat observations.”The findings come from nearly 8 years of observations by NASA’s Cassini spacecraft in the Saturn system.

Ciel & Espace photos Premières images d'une étoile cannibale Située dans la constellation du Lièvre, SS Leporis est un système d'étoiles binaire inhabituel. Depuis longtemps, les astronomes suspectent l'étoile la moins évoluée de cannibaliser sa compagne vieillissante, une géante rouge froide, qui se trouve être la plus évoluée mais aussi, paradoxalement, la moins massive des deux étoiles (1). Cette propriété atypique témoigne d'une forte voracité de la part de l'étoile peu évoluée, au point d'inverser les rapports de masse. En effet, observée depuis la Terre, SS Leporis apparaît, sur la voute céleste, à peine plus grosse qu'un homme à la surface de la Lune. Les données acquises montrent que la distance séparant les deux étoiles est légèrement supérieure à la distance entre le Soleil et la Terre, et que la géante rouge s'avère moins grande que prévu, sa taille étant comparable à l'orbite de Mercure. © Nicolas Blind © Nicolas Blind/BinSim Vision d'artiste de la binaire SS Leporis réalisée avec le logiciel BinSin à partir des résultats de l'étude.

Carte du ciel Cette carte du ciel vous permet de recréer l’aspect du ciel à un moment donné depuis n’importe quel point de la Terre. Elle indique la position du Soleil, de la Lune, des planètes Mercure, Vénus, Mars, Jupiter, Saturne, ainsi que des 1377 étoiles les plus brillantes du ciel. Toutes les valeurs de lieu et de temps sont calculées automatiquement à partir des coordonnées géographiques et de l’information horaire fournies par votre ordinateur. Si vous refusez l’utilisation de vos coordonnées géographiques, l’application se positionne automatiquement sur Paris. Les algorithmes sont basés sur le livre « Calculs astronomiques à l’usage des amateurs », Jean Meeus, Société astronomique de France, Paris, 1986. Dernières mises à jour : Version 1.6 (17/09/2016) : Possibilité de faire tourner la carte avec la souris. Version 1.5 (01/11/2015) : Géolocalisation automatique. Version 1.4 (25/10/2015) : Taille dynamique et support des écrans haute définition et retina. Quelques remarques sur les commandes :

Preview of a Forthcoming Supernova Picture Album: Entire Collection Search all of HubbleSite Search Picture Album Picture Album: Entire Collection Results per page: View inShowcase Show Titles List Highest Resolution First search | site map | reference desk | about us | contact us | copyright Des images d'une étoile cannibale capturées pour la première fois Des astronomes français viennent d’obtenir la meilleure image jamais réalisée d'une étoile cannibalisée par sa compagne stellaire. Située dans la constellation du Lièvre, SS Leporis est un système d'étoiles binaire inhabituel. Cela fait longtemps que les astronomes suspectent l'étoile la moins évoluée de cannibaliser sa compagne vieillissante, une géante rouge froide moins massive. Cette propriété atypique témoigne d'une forte voracité de la part de l'étoile peu évoluée, au point d'inverser les rapports de masse. Avez-vous déjà partagé cet article? Partager sur Facebook Partager sur Twitter Pour mieux comprendre la nature et l'importance de ce phénomène, il était nécessaire d'étudier la dynamique du système et d'en observer les parties les plus internes, jusqu'alors invisibles pour les télescopes classiques, explique le CNRS dans un communiqué. Un transfert de matière sous forme de vent stellaire

SINGS Hubble tuning fork poster This poster displays the 75 SINGS galaxies arranged in a tuning fork based on their optical morphology. The color images of each galaxy were created from the SINGS IRAC 3.6um (blue), IRAC 8.0um (green), and MIPS 24um (red) images. This poster represents summarizes a large amount of work carried about by the SINGS team in writing the original proposal, planning the observations, reducing the data, and many studies devoted to understanding what the images mean. Most of the work for the poster itself was carried about by Karl Gordon with significant help from Robert Hurt. Many SINGS team members and Spitzer Science Center staff contributed helpful comments and advice. The Spitzer Science Center has a feature article on this poster. Questions about the poster should be directed to Karl Gordon (kgordon@stsci.edu). More details on how the poster was constructed will be added soon. The poster has been professionally printed in quantity by TrojanLitho. The poster is sized to print 36" by 42".

An enigmatic blue bubble in space There is something aesthetically pleasing about symmetry, whether it’s on Earth or as it is in the heavens. That may be one of the reasons I love planetary nebulae, the eerie and beautiful structures created when dying stars cast off their outer layers. They come in many strange shapes, and oddly it’s quite rare to find one that appears perfectly circular. But they do exist, and one of the best examples I have seen yet is Abell 33, the glowing winds from a star located something like 1500 light years away: How gorgeous is that? A few things jumped out at me. Second, it looks like the central star may be a binary, two stars orbiting each other. Also, it’s obvious the central star(s) is off-center! Third, of course, is how circular it is. Apparently, though, for most stars something happens to increase their spin before they become planetary nebulae. But if you look more closely at the picture of Abell 33, things get weirder. Related Posts:

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