File:Saturn's rings in visible light and radio.jpg

原始文件 (5,776 × 864像素,文件大小:491 KB,MIME类型:image/jpeg


图像 of the year
图像 of the year
Featured 图像

维基共享资源维基百科

本文件是2007年年度图片比赛的候选图片。
本文件是维基共享资源特色图片(Featured pictures),并被视为最好的图像之一。

 本文件是英语维基百科特色图片(Featured pictures),并被视为最好的图像之一。

如果你拥有相似质量的可采用适当著作权许可协议发布的图像,一定要上传标记推荐它。

摘要

描述
English: Cassini instruments provide complementary information about the structure of Saturn's rings. Narrow and wide angle cameras provide images in the visible region of the electromagnetic spectrum much like a digital camera does. The images have information about how the ring structure differs both with distance from the planet and with position around the equatorial circle. However, resolution is usually limited to few kilometers at best.

Radio and stellar occultations of the rings also provide important information about ring structure, but only along a one-dimensional track through the rings. The radial resolution can be as fine as 50 meters (164 feet). An "image" is then constructed by assuming circular symmetry over the ring region of interest. Color is usually added to encode other information related to the observed structure.

This image compares structure of Saturn's rings observed by these two approaches. The upper half is a natural color mosaic of images of the illuminated side of the rings by the Cassini narrow-angle camera (see PIA06175). The bottom simulated image is constructed from a radio occultation observation conducted on May 3, 2005. For another view created using this process, see PIA07872. Color in the lower image is used to represent information about ring particle sizes.

Three simultaneous radio signals of 0.94, 3.6, and 13 centimeter wavelength (Ka-, X-, and S-bands) were sent from Cassini through the rings to Earth. The observed change of each signal as Cassini moved behind the rings provided a profile of the distribution of ring material as a function of distance from Saturn, or an optical depth profile. This simulated image was constructed from the measured optical depth profiles.

Shades of purple, primarily over most of the middle ring, the B ring, and the inner portion of the outer ring, the A ring, indicate regions where there is a lack of particles less than 5 centimeters (about 2 inches) in diameter. Green and blue shades indicate regions where there are particles of sizes smaller than 5 centimeters (2 inches) and 1 centimeter (less than one third of an inch), respectively, primarily in the outer A ring and within most of the inner ring, the C ring. The saturated broad white band near the middle of the B ring is the densest region of the rings, over which two of the three radio signals were blocked at 10-kilometer (6-mile) resolution, preventing accurate color representation. From other evidence in the radio observations, all ring regions appear to be populated by a broad range particle size distribution that extends to boulder sizes (several to many meters across).

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The 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 was designed, developed and assembled at JPL. The radio science team is based at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For more information on the radio science team visit http://saturn.jpl.nasa.gov/spacecraft/instruments-cassini-rss.cfm. The imaging team homepage is at http://ciclops.org.


Français : Les instruments de la sonde Cassini fournissent des information différentes et complémentaires sur la structure des anneaux de Saturne. Les appareils photo à grand angle et à longue focale font des photos d'une façon très comparable à celle d'un appareil numérique. Ces images permettent de voir la structure des anneaux à la fois en fonction de la distance à la planète et le long du plan équatorial. Cependant la résolution est limitée à quelques kilomètres.

Les ondes radio et les occultations stellaires permettent d'obtenir une bien meilleure résolution (50 mètres), mais uniquement dans le sens radial. Une image est reconstruite en supposant que les anneaux ont une symétrie radiale dans la zone considérée. De la couleur est souvent ajoutée pour donner d'autres informations sur la structure observée.
Cette image compare la structure des anneaux de Saturne observée avec ces deux méthodes différentes. L'image du haut est une image en vraies couleurs obtenues avec la caméra à longue focale. L'image du bas a été construite après l'observation d'une occultation d'une source radio par les anneaux de la planète réalisée le 3 Mai 2005. La couleur sur l'image du bas donne des informations sur la taille des particules constituant les anneaux.

La mission Cassini-Huygens est une mission conjointe de la NASA, de l'ESA et de l'ISA. L'orbiteur Cassini et ses caméras ont été conçus et construit au JPL à Passadena, en Californie. Le centre de traitement des images est à Boulder, au Colorado (États-Unis).
中文:土星光环
日期 Visible light image taken 2004-12-12; radio data acquired 2005-05-03; combined image released 2005-05-23
来源 http://photojournal.jpl.nasa.gov/catalog/PIA07874
作者 NASA / JPL / Space Science Institute
其他版本
本图像或视频收录于美国国家航空航天局 (NASA)喷气推进实验室(Jet Propulsion Laboratory),其照片编号是: PIA07874

此标签不表示文件的著作权状态。任何文件在附有此标签的同時还需要一个有效的著作权标签请参阅许可协议说明页面以了解更多信息。

许可协议

Public domain 本文件完全由NASA创作,在美国属于公有领域。根据NASA的版权方针,NASA的材料除非另有声明否则不受版权保护。(参见Template:PD-USGov/zhNASA版权方针页面JPL图片使用方针。)
警告:

说明

添加一行文字以描述该文件所表现的内容

此文件中描述的项目

描繪內容

文件历史

点击某个日期/时间查看对应时刻的文件。

日期/时间缩⁠略⁠图大小用户备注
当前2007年10月20日 (六) 21:212007年10月20日 (六) 21:21版本的缩略图5,776 × 864(491 KB)WolfmanSF{{Information |Description= Cassini instruments provide complementary information about the structure of Saturn's rings. Narrow and wide angle cameras provide images in the visible region of the electromagnetic, spectrum much like a digital camera does. T

全域文件用途

以下其他wiki使用此文件:

查看此文件的更多全域用途