Archivo:The Day the Earth Smiled - PIA17172.jpg

Contenido de la página no disponible en otros idiomas.
De Wikipedia, la enciclopedia libre

Ver la imagen en su resolución original(9000 × 3500 píxeles; tamaño de archivo: 4,78 MB; tipo MIME: image/jpeg)

Resumen

Descripción
English: On July 19, 2013, in an event celebrated the world over, NASA's Cassini spacecraft slipped into Saturn's shadow and turned to image the planet, seven of its moons, its inner rings -- and, in the background, our home planet, Earth.

With the sun's powerful and potentially damaging rays eclipsed by Saturn itself, Cassini's onboard cameras were able to take advantage of this unique viewing geometry. They acquired a panoramic mosaic of the Saturn system that allows scientists to see details in the rings and throughout the system as they are backlit by the sun. This mosaic is special as it marks the third time our home planet was imaged from the outer solar system; the second time it was imaged by Cassini from Saturn's orbit; and the first time ever that inhabitants of Earth were made aware in advance that their photo would be taken from such a great distance.

With both Cassini's wide-angle and narrow-angle cameras aimed at Saturn, Cassini was able to capture 323 images in just over four hours. This final mosaic uses 141 of those wide-angle images. Images taken using the red, green and blue spectral filters of the wide-angle camera were combined and mosaicked together to create this natural-color view. A brightened version with contrast and color enhanced (Figure 1), a version with just the planets annotated (Figure 2), and an annotated version (Figure 3) are shown above.

This image spans about 404,880 miles (651,591 kilometers) across.

The outermost ring shown here is Saturn's E ring, the core of which is situated about 149,000 miles (240,000 kilometers) from Saturn. The geysers erupting from the south polar terrain of the moon Enceladus supply the fine icy particles that comprise the E ring; diffraction by sunlight gives the ring its blue color. Enceladus (313 miles, or 504 kilometers, across) and the extended plume formed by its jets are visible, embedded in the E ring on the left side of the mosaic.

At the 12 o'clock position and a bit inward from the E ring lies the barely discernible ring created by the tiny, Cassini-discovered moon, Pallene (3 miles, or 4 kilometers, across). (For more on structures like Pallene's ring, see PIA08328). The next narrow and easily seen ring inward is the G ring. Interior to the G ring, near the 11 o'clock position, one can barely see the more diffuse ring created by the co-orbital moons, Janus (111 miles, or 179 kilometers, across) and Epimetheus (70 miles, or 113 kilometers, across). Farther inward, we see the very bright F ring closely encircling the main rings of Saturn.

Following the outermost E ring counter-clockwise from Enceladus, the moon Tethys (662 miles, or 1,066 kilometers, across) appears as a large yellow orb just outside of the E ring. Tethys is positioned on the illuminated side of Saturn; its icy surface is shining brightly from yellow sunlight reflected by Saturn. Continuing to about the 2 o'clock position is a dark pixel just outside of the G ring; this dark pixel is Saturn's Death Star moon, Mimas (246 miles, or 396 kilometers, across). Mimas appears, upon close inspection, as a very thin crescent because Cassini is looking mostly at its non-illuminated face.

The moons Prometheus, Pandora, Janus and Epimetheus are also visible in the mosaic near Saturn's bright narrow F ring. Prometheus (53 miles, or 86 kilometers, across) is visible as a faint black dot just inside the F ring and at the 9 o'clock position. On the opposite side of the rings, just outside the F ring, Pandora (50 miles, or 81 kilometers, across) can be seen as a bright white dot. Pandora and Prometheus are shepherd moons and gravitational interactions between the ring and the moons keep the F ring narrowly confined. At the 11 o'clock position in between the F ring and the G ring, Janus (111 miles, or 179 kilometers, across) appears as a faint black dot. Janus and Prometheus are dark for the same reason Mimas is mostly dark: we are looking at their non-illuminated sides in this mosaic. Midway between the F ring and the G ring, at about the 8 o'clock position, is a single bright pixel, Epimetheus. Looking more closely at Enceladus, Mimas and Tethys, especially in the brightened version of the mosaic, one can see these moons casting shadows through the E ring like a telephone pole might cast a shadow through a fog.

In the non-brightened version of the mosaic, one can see bright clumps of ring material orbiting within the Encke gap near the outer edge of the main rings and immediately to the lower left of the globe of Saturn. Also, in the dark B ring within the main rings, at the 9 o'clock position, one can see the faint outlines of two spoke features, first sighted by NASA's Voyager spacecraft in the early 1980s and extensively studied by Cassini.

Finally, in the lower right of the mosaic, in between the bright blue E ring and the faint but defined G ring, is the pale blue dot of our planet, Earth. Look closely and you can see the moon protruding from the Earth's lower right. (For a higher resolution view of the Earth and moon taken during this campaign, see PIA14949.) Earth's twin, Venus, appears as a bright white dot in the upper left quadrant of the mosaic, also between the G and E rings. Mars also appears as a faint red dot embedded in the outer edge of the E ring, above and to the left of Venus.

For ease of visibility, Earth, Venus, Mars, Enceladus, Epimetheus and Pandora were all brightened by a factor of eight and a half relative to Saturn. Tethys was brightened by a factor of four. In total, 809 background stars are visible and were brightened by a factor ranging from six, for the brightest stars, to 16, for the faintest. The faint outer rings (from the G ring to the E ring) were also brightened relative to the already bright main rings by factors ranging from two to eight, with the lower-phase-angle (and therefore fainter) regions of these rings brightened the most. The brightened version of the mosaic was further brightened and contrast-enhanced all over to accommodate print applications and a wide range of computer-screen viewing conditions.

Some ring features -- such as full rings traced out by tiny moons -- do not appear in this version of the mosaic because they require extreme computer enhancement, which would adversely affect the rest of the mosaic. This version was processed for balance and beauty.

This view looks toward the unlit side of the rings from about 17 degrees below the ring plane. Cassini was approximately 746,000 miles (1.2 million kilometers) from Saturn when the images in this mosaic were taken. Image scale on Saturn is about 45 miles (72 kilometers) per pixel.

This mosaic was made from pictures taken over a span of more than four hours while the planets, moons and stars were all moving relative to Cassini. Thus, due to spacecraft motion, these objects in the locations shown here were not in these specific places over the entire duration of the imaging campaign. Note also that Venus appears far from Earth, as does Mars, because they were on the opposite side of the sun from Earth.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
Français : Photomontage intitulée « Le Jour où la Terre a souri ». La sonde Cassini-Huygens a profité d'une position favorable pour photographier une « éclipse solaire » de la planète Saturne le 19 juillet 2013. Ce photomontage de 141 photos retouchées, publié le 12 novembre 2013, montre tous les anneaux de Saturne.
العربية : اليوم الذي ابتسمت فيه الأرض؛ 19 تُّموز (يوليو) 2013م، الذي قام فيه المسبار الفضائي كاسيني بتصوير زُحل ونظامه الحلقي كله أثناء كسوف الشمس، بالإضافة إلى الأرض والمريخ والزُهرة، وبعض أقمار زحل. كانت هذه هي أول صورة تلتقط لأربع كواكب في وقت واحد. دُعي جميع شعوب العالَم للتفكر في مكانهم في الكون، وللإعجاب بالحياة على الأرض، في نفس الوقت الذي يتم التقاط الصورة فيه، للبحث والابتسام في الاحتفالية.
Fecha
Fuente http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA17172
Autor NASA/JPL-Caltech/SSI
Otras versiones PIA17172 Saturn eclipse mosaic bright crop.jpg - cropped version (8,400 × 3,500 pixels, 4.49 MB); PIA17172 - The Day the Earth Smiled.jpg - uncropped, darker, more compressed version (9,000 × 3,500 pixels, 739 KB); The Day the Earth smiled.jpg - half size, darker, annotated version (4,500 × 1,750 pixels, 1.64 MB); Saturn-day-earth-smiled-1000x600.png - smaller png version (1,000 × 600 pixels, 243 KB); The Faces of 'Wave at Saturn'.jpg - faces mosaic version (15,000 × 5,833 pixels, 25.66 MB)

Featured imagen

Wikimedia CommonsWikipedia

Esta imagen es considerada una de las mejores de Wikimedia Commons (Imágenes destacadas).

Wikipedia
 Esta imagen es considerada una de las mejores de la Wikipedia en idioma árabe (صور مختارة).
 Esta imagen es considerada una de las mejores de la Wikipedia en idioma inglés (Featured pictures).
 Esta imagen es considerada una de las mejores de la Wikipedia en idioma hebreo (תמונות מומלצות).

Si tienes una imagen de calidad similar que pueda ser publicada con licencia libre, súbela aquí, etiquétala y nomínala.

Licencia

Public domain Este archivo es de dominio público porque fue creado por la NASA. Las políticas sobre copyright de la NASA estipulan que «el material de la NASA no está protegido con copyright a menos que se indique lo contrario». (Políticas sobre copyright de la NASA o Políticas sobre la utilización de imágenes del Jet Propulsion Laboratory).
Advertencias:
  • El uso del logotipo de la NASA (incluidos el logotipo actual y los anteriores) está restringido.
  • El sitio web de la NASA almacena una gran cantidad de imágenes del Programa Espacial de la URSS, de la Agencia Espacial Federal Rusa y otras agencias espaciales no estadounidenses. Estas imágenes no son de dominio público.
  • Material del Telescopio espacial Hubble puede tener copyright si no proviene explícitamente del Space Telescope Science Institute. [1]
  • Todo el material creado por la sonda espacial SOHO está protegido por copyright y requiere permiso para ser utilizado con fines comerciales o no educativos. [2]
  • Las imágenes que figuran en el sitio web Astronomy Picture of the Day (APOD) pueden tener copyright. [3]
Annotations
InfoField
This image is annotated: View the annotations at Commons

Leyendas

Fotomontaje titulado « El día que la Tierra sonrió ».

Elementos representados en este archivo

representa a

Historial del archivo

Haz clic sobre una fecha y hora para ver el archivo tal como apareció en ese momento.

Fecha y horaMiniaturaDimensionesUsuarioComentario
actual17:59 12 nov 2013Miniatura de la versión del 17:59 12 nov 20139000 × 3500 (4,78 MB)Stas1995User created page with UploadWizard

La siguiente página usa este archivo:

Uso global del archivo

Las wikis siguientes utilizan este archivo:

Ver más uso global de este archivo.