ESA - Space Science - A hot start might explain geysers on Enceladus

Space Science

About Space Science ESA's 'Cosmic Vision'Science & Technology in-depth

Multimedia

Science images Science videos Animations Downloads Sounds from space

Media centre

Press Releases Press kits ESA Television

Resources

Reference section Glossary FAQs

Science missions

Services

Help Legal disclaimer Comments Subscribe

RSS feeds

ESA Sci on Twitter

Article Images

A hot start might explain geysers on Enceladus

12 March 2007

Back to article

Download:

HI-RES JPG (Size: 1244 kb)

As it swooped past the south pole of Saturn's moon Enceladus on 14 July 2005, Cassini acquired high resolution views of this puzzling ice world. From afar, Enceladus exhibits a bizarre mixture of softened craters and complex, fractured terrains. This large mosaic of 21 narrow-angle camera images have been arranged to provide a full-disc view of the anti-Saturn hemisphere on Enceladus. This mosaic is a false-colour view that includes images taken at wavelengths from the ultraviolet to the infrared portion of the spectrum, and is similar to another, lower resolution false-colour view obtained during the flyby. In false-colour, many long fractures on Enceladus exhibit a pronounced difference in colour (represented here in blue) from the surrounding terrain.

A leading explanation for the difference in colour is that the walls of the fractures expose outcrops of coarse-grained ice that are free of the powdery surface materials that cover flat-lying surfaces.

The original images in the false-colour mosaic range in resolution from 350 to 67 metres per pixel and were taken at distances ranging from 61 300 to 11 100 kilometres from Enceladus. The mosaic is also part of a movie sequence of images from this flyby.

Credits: NASA/JPL/Space Science Institute

Back to article

Download:

HI-RES JPEG (Size: 135 kb)

HI-RES TIFF (Size: 1058 kb)

The ice jets of Enceladus send particles streaming into space hundreds of kilometres above the south pole of this spectacularly active moon. Some of the particles escape to form the diffuse E ring around Saturn. This colour-coded image was processed to enhance faint signals, making the contours and extent of the fainter, larger-scale component of the plume easier to see.

The bright strip behind and above Enceladus (505 kilometres) is the E ring, in which this intriguing body resides. The small round object at far left is a background star.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on 24 March 2006 at a distance of approximately 1.9 million kilometres from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 162 degrees. Image scale is 11 kilometres per pixel.

Credits: NASA/JPL/Space Science Institute

Back to article

Download:

HI-RES JPG (Size: 149 kb)

HI-RES TIFF (Size: 1565 kb)

Plumes of icy material extend above the southern polar region of Saturn's moon Enceladus, as imaged by the Cassini spacecraft in January 2005. The monochrome view is presented along with a colour-coded image on the right. The view in this image is perpendicular to the tiger stripe fractures that straddle the south pole. Another plume view, was taken one month later and looks along the tiger stripe fractures. Images like these are being analyzed by scientists as they seek to explain the processes that could be producing such incredible features. As reported in the journal Science on 10 March 2006, imaging scientists believe that the plumes are geysers erupting from pressurized subsurface reservoirs of liquid water above 0°C.

These images were taken with the Cassini spacecraft narrow-angle camera at a distance of approximately 209 400 kilometres from Enceladus at a Sun-Enceladus-spacecraft, or phase, angle of 148 degrees. The image scale is about 1.3 kilometres per pixel.

The mosaic is an orthographic projection centred at 46.8 degrees south latitude, 188 degrees west longitude, and has an image scale of 67 metres per pixel. The original images ranged in resolution from 67 metres per pixel to 350 metres per pixel and were taken at distances ranging from 11 100 to 61 300 kilometres from Enceladus.

Credits: NASA/JPL/Space Science Institute

Back to article

Download:

HI-RES JPG (Size: 510 kb)

Recent Cassini images of Saturn's moon Enceladus backlit by the Sun show the fountain-like sources of the fine spray of material that towers over the south polar region. The image was taken looking more or less broadside at the 'tiger stripe' fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb of the moon. This enhanced and false-coloured image shows the enormous extent of the fainter, larger-scale component of the plume.

Credits: NASA/JPL/Space Science Institute

At Saturn and Titan

More about...