Image:169141main piaa09178.jpg
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Image en plus haute résolution (4 279 × 3 559 pixels, taille du fichier : 7,22 Mio, type MIME : image/jpeg)
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| Description |
English: This infrared image from NASA's Spitzer Space Telescope shows the Helix Nebula, a cosmic starlet often photographed by amateur astronomers for its vivid colors and eerie resemblance to a giant eye.
The nebula, located about 700 light-years away in the constellation Aquarius, belongs to a class of objects called planetary nebulae. Discovered in the 18th century, these colorful beauties were named for their resemblance to gas-giant planets like Jupiter. Planetary nebulae are the remains of stars that once looked a lot like our sun. When sun-like stars die, they puff out their outer gaseous layers. These layers are heated by the hot core of the dead star, called a white dwarf, and shine with infrared and visible colors. Our own sun will blossom into a planetary nebula when it dies in about five billion years. In Spitzer's infrared view of the Helix nebula, the eye looks more like that of a green monster's. Infrared light from the outer gaseous layers is represented in blues and greens. The white dwarf is visible as a tiny white dot in the center of the picture. The red color in the middle of the eye denotes the final layers of gas blown out when the star died. The brighter red circle in the very center is the glow of a dusty disk circling the white dwarf (the disk itself is too small to be resolved). This dust, discovered by Spitzer's infrared heat-seeking vision, was most likely kicked up by comets that survived the death of their star. Before the star died, its comets and possibly planets would have orbited the star in an orderly fashion. But when the star blew off its outer layers, the icy bodies and outer planets would have been tossed about and into each other, resulting in an ongoing cosmic dust storm. Any inner planets in the system would have burned up or been swallowed as their dying star expanded. So far, the Helix nebula is one of only a few dead-star systems in which evidence for comet survivors has been found. This image is made up of data from Spitzer's infrared array camera and multiband imaging photometer. Blue shows infrared light of 3.6 to 4.5 microns; green shows infrared light of 5.8 to 8 microns; and red shows infrared light of 24 microns.Français : Image infrarouge de la nébuleuse de l'hélice prise par le téléscope spatial Spitzer de la NASA.
La nébuleuse de l'hélice est un grand classique de la photographie astronomique amateur à cause de ses belles couleurs et de sa resemblance à un œil géant. Cet objet situé dans la constellation des poissons est appellé une nébuleuse planétaire. Découvertes au cours du XVIIIè siècles, les nébuleuses planétaires doivent leur nom à leur ressemblance avec des planète géantes gazeuses comme Jupiter. Cependant, leur formation est toute différente: lorsqu'une étoile de la taille du soleil arrive au terme de sa vie, elle expulse ses couches extérieures dans l'espace environant. Ce gaz est chauffé par ce qui reste du cœur de l'étoile, une naine blanche, et brille de couleurs visibles et infrarouges. Notre soleil formera une telle nébuleuse planétaire dans cinq milliards d'années environ. Dans l'image prise par Spitzer, l'œil qui nous regarde semble appartenir à un monstre vert. Le vert et le bleu correspond aux couches gazeuses les plus externes. La naine blanche est visible comme un petit point blanc au centre de l'image. Le rouge correspond aux dernières couches gazeuses expulsées par l'étoile. La petite zone rouge autour de l'étoile correspondrait à de la lumière émise par un disque de poussières (lui même trop petit pour être vu). Cette poussiere proviendrait de comètes ayant survécu à la mort violente de leur étoile. La nébuleuse de l'hélice est l'une des seules ou de telles comètes semblent exister. Lorsque cette étoile s'est transformée en géante rouge, les planètes les plus internes ont été absorbées. Lorsqu'elle a éjecté ses couches extérieures, les autres planètes gravitant autour d'elle ont probablement été détruites, et la survie de comètes est en soi difficile à expliquer. Cette image a été réalisée à partir de données obtenues par la caméra infrarouge de Spitzer et son photomètre multifréquence. Le bleu correspond à des longueurs d'ondes de 3,6 à 4,5 microns, le vert de 5,8 à 8 microns, et le rouge a des longueurs d'ondes de 24 microns. |
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| Date |
2007-02-12 |
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| Author |
NASA/JPL-Caltech/Univ. of Ariz. |
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| Permission (Reusing this image) |
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This file was a candidate on Picture of the Year 2007. This is a featured picture on Wikimedia Commons: it is considered one of our finest images. If you have an image of similar quality that can be published under a suitable copyright license, be sure to upload it, tag it, and nominate it. |
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This image was selected as a picture of the day for May 15, 2007. It was captioned as followed:
English: Helix Nebula
Беларуская: Планетарная туманнасць Слімак (NGC 7293)
Česky: Planetární mlhovina Helix
Deutsch: Helixnebel, NGC 7293
English: Helix Nebula
Español: Nebulosa Helix (NGC 7293).
Magyar: A Csiga-köd
Italiano: La nebulosa Elica (NGC 7293)
日本語: せん状星雲 (NGC 7293)
Nederlands: Helixnevel (NGC 7293)
Polski: Mgławica Helix (NGC 7293)
Português: Imagem da Nebulosa de Helix. (NGC 7293)
Română: Nebuloasa Helix
Русский: Туманность Улитка
Slovenčina: Hmlovina Slimák (NGC 7293)
Српски / Srpski: Хеликс Небула
Svenska: Helixnebulosan, NGC 7293
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| Date et heure | Dimensions | Utilisateur | Commentaire | |
|---|---|---|---|---|
| actuel | 13 février 2007 à 05:43 | 4 279×3 559 (7,22 Mio) | Startaq | ({{Information |Description=This infrared image from NASA's Spitzer Space Telescope shows the Helix nebula, a cosmic starlet often photographed by amateur astronomers for its vivid colors and eerie resemblance to a giant eye. The nebula, located about 700) |
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| Description de l’image | This infrared image from NASA's Spitzer Space Telescope shows the Helix nebula, a cosmic starlet often photographed by amateur astronomers for its vivid colors and eerie resemblance to a giant eye.
The nebula, located about 700 light-years away in the constellation Aquarius, belongs to a class of objects called planetary nebulae. Discovered in the 18th century, these cosmic butterflies were named for their resemblance to gas-giant planets. Planetary nebulae are actually the remains of stars that once looked a lot like our sun. When sun-like stars die, they puff out their outer gaseous layers. These layers are heated by the hot core of the dead star, called a white dwarf, and shine with infrared and visible-light colors. Our own sun will blossom into a planetary nebula when it dies in about five billion years. In Spitzer's infrared view of the Helix nebula, the eye looks more like that of a green monster's. Infrared light from the outer gaseous layers is represented in blues and greens. The white dwarf is visible as a tiny white dot in the center of the picture. The red color in the middle of the eye denotes the final layers of gas blown out when the star died. The brighter red circle in the very center is the glow of a dusty disk circling the white dwarf (the disk itself is too small to be resolved). This dust, discovered by Spitzer's infrared heat-seeking vision, was most likely kicked up by comets that survived the death of their star. Before the star died, its comets and possibly planets would have orbited the star in an orderly fashion. But when the star blew off its outer layers, the icy bodies and outer planets would have been tossed about and into each other, resulting in an ongoing cosmic dust storm. Any inner planets in the system would have burned up or been swallowed as their dying star expanded. The Helix nebula is one of only a few dead-star systems in which evidence for comet survivors has been found. This image is made up of data from Spitzer's infrared array camera and multiband imaging photometer. Blue shows infrared light of 3.6 to 4.5 microns; green shows infrared light of 5.8 to 8 microns; and red shows infrared light of 24 microns. |
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| Orientation | Normale |
| Résolution horizontale | 72 dpi |
| Résolution verticale | 72 dpi |
| Logiciel utilisé | Adobe Photoshop CS2 Windows |
| Date de modification | 9 février 2007 à 15:05 |
| Espace colorimétrique | sRGB |
