* Astronomy

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RE: Enceladus

Blobrana · L

Cassini to Dip into Enceladus Spray Again

Less than three weeks after its last visit to the Saturnian moon Enceladus, NASA's Cassini spacecraft returns for an encore. At closest approach on April 14, the spacecraft will be just as low over the moon's south polar region as it was on March 27 -- 46 miles, or 74 kilometres.
Like the last, this latest flyby is mainly designed for Cassini's ion and neutral mass spectrometer, which will "taste" the particles in the curious jets spraying from the moon's south polar region.
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Is it Snowing Microbes on Enceladus?

There's a tiny moon orbiting beyond Saturn's rings that's full of promise, and maybe -- just maybe -- microbes.
In a series of tantalisingly close flybys to the moon, named "Enceladus," NASA's Cassini spacecraft has revealed watery jets erupting from what may be a vast underground sea. These jets, which spew through cracks in the moon's icy shell, could lead back to a habitable zone that is uniquely accessible in all the solar system.
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Credit: NASA/JPL/Space Science Institute

This image of Enceladus was taken by the Cassini spacecraft on the 27th March, 2012, when it was approximately 282,725 kilometres away.
The image was taken using the CL1 and IR1 filters.

Blobrana · L

Cassini to Make Closest Pass Yet over Enceladus South Pole

NASA's Cassini spacecraft is preparing to make its lowest pass yet over the south polar region of Saturn's moon Enceladus, where icy particles and water vapour spray out in glittering jets. The closest approach, at an altitude of about 74 kilometres, will occur around 18:30 UT on March 27.
This flyby is primarily designed for Cassini's ion and neutral mass spectrometer, which will attempt to "taste" particles from the jets. Scientists using this spectrometer will utilise the data to learn more about the composition, density and variability of the plume. The Cassini plasma spectrometer, which team members worked to return to service so it could gather high-priority measurements during this flyby, will also be analysing Saturn's magnetic and plasma environment near Enceladus and sampling the plume material near closest approach.
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Credit: NASA/JPL/Space Science Institute

This image of Enceladus was taken by the Cassini spacecraft on March 10, 2012 when it was approximately 183,005 kilometres away.
The image was taken using the CL1 and CL2 filters.

Blobrana · L

Extraterrestrial Ocean

Enceladus has always been thought of as one of the more remarkable members of Saturn's marble bag of satellites. For one thing, it's dazzlingly bright. The percentage of sunlight that any body in the solar system reflects back is known as its albedo, and it's determined mostly by the colour of its ground cover. For all the silvery brilliance of a full moon on a cloudless night, the albedo of our own drab satellite is a muddy 12%, owing mostly to the grey dust that covers it. The albedo of Enceladus, on the other hand, approaches a mirrorlike 100%.
That likely meant that the surface was covered with ice crystals - and, what's more, that those crystals get regularly replenished.
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Saturn's Rings and Enceladus

A crescent Enceladus appears with Saturn's rings in this Cassini spacecraft view of the moon.
The image was taken with Cassini's narrow-angle camera on 4 January at a distance of 291 000 km from Enceladus. Image scale is about 2 km per pixel.

Blobrana · L

Enceladus is the sixth-largest of the moons of Saturn. It was discovered in 1789 by William Herschel.
In 2005 the Cassini spacecraft performed several close flybys of Enceladus, revealing the moon's surface and environment in greater detail. In particular, the probe discovered a water-rich plume venting from the moon's south polar region. This discovery, along with the presence of escaping internal heat and very few (if any) impact craters in the south polar region, shows that Enceladus is geologically active today.
Analysis of the outgassing suggests that it originates from a body of sub-surface liquid water, which along with the unique chemistry found in the plume, has fuelled speculations that Enceladus may be important in the study of astrobiology.
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Blobrana · L

The moon Enceladus, one of the jewels of the Saturn system, sparkles peculiarly bright in new images obtained by NASA's Cassini spacecraft. The images of the moon, the first ever taken of Enceladus with Cassini's synthetic aperture radar, reveal new details of some of the grooves in the moon's south polar region and unexpected textures in the ice. These images, obtained on Nov. 6, 2011, are the highest-resolution images of this region obtained so far.
The area on Enceladus observed by Cassini's radar instrument does not include the famous "tiger stripes," fissures that eject great plumes of ice particles and water vapor, but covers regions just a few hundred miles away from the stripes. Scientists are scrutinizing an area around 63 degrees south latitude and 51 degrees west longitude that appears to be very rough, a texture that shows up as very bright in the radar images.
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Cassini Flyby Focuses on Saturn's Moon Enceladus

Credit: NASA/JPL-Caltech/Space Science Institute

NASA's Cassini spacecraft obtained this unprocessed image of Enceladus on Nov. 6, 2011 and received on Earth November 07, 2011.
The camera was pointing toward Enceladus at approximately 144,790 kilometres away, and the image was taken using the CL1 and CL2 filters.

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Blobrana · L

Orion's Belt Lights Up Cassini's View of Enceladus

NASA's Cassini mission will take advantage of the position of two of the three stars in Orion's belt when the spacecraft flies by Saturn's moon Enceladus on Wed., Oct. 19. As the hot, bright stars pass behind the moon's icy jets, Cassini's ultraviolet imaging spectrograph will acquire a two-dimensional view of these dramatic plumes of water vapour and icy material erupting from the moon's southern polar region. This flyby is the mission's first-ever opportunity to probe the jets with two stars simultaneously, a dual stellar occultation.
From Cassini's viewpoint, the closest of Orion's stars will appear about 15 kilometres above the moon's limb, or outer edge. The second star will appear higher, about 30 kilometres from the limb. In the foreground will be Enceladus' icy plumes, which extend hundreds of miles into space.
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