Cassini Prepares For Close Flyby of Saturn's Geyser-Spewing Moon
Written by Nancy Atkinson
Saturn's tiny moon Enceladus is of big interest to planetary scientists trying to understand the dynamics of the moon's geysers and fissures. On August 11, the Cassini spacecraft will swoop by Enceladus for a close flyby, just 50 kilometers (30 miles) from the surface, with the fractures, or "tiger stripes" near the moon's south pole, where icy jets erupt as the target of study for the Cassini instruments. "Our main goal is to get the most detailed images and remote sensing data ever of the geologically active features on Enceladus," said Paul Helfenstein, a Cassini imaging team associate at Cornell University in Ithaca, NY. "From this data we may learn more about how eruptions, tectonics, and seismic activity alter the moon's surface. We will get an unprecedented high-resolution view of the active area immediately following the closest approach."
Cassini will actually try to see inside one of the fissures in high resolution, which may provide more information on the terrain and depth of the fissures, as well as the size and composition of the ice grains inside. Refined temperature data could help scientists determine if water, in vapor or liquid form, lies close to the surface and better refine their theories on what powers the jets.
Cassini discovered evidence for the geyser-like jets on Enceladus in 2005, finding that the continuous eruptions of ice water create a gigantic halo of ice and gas around Enceladus, which helps supply material to Saturn's E-ring. Just after closest approach, all of the spacecraft's cameras — covering infrared wavelengths, where temperatures are mapped, as well as visible light and ultraviolet — will focus on the fissures running along the moon's south pole. That is where the jets of icy water vapor emanate and erupt hundreds of miles into space. The image resolution will be as fine as 7 meters per pixel (23 feet) and will cover known active spots on three of the prominent "tiger stripe" fractures.
This will be Cassini's second flyby of Enceladus this year. During the last flyby in March, the spacecraft snatched up precious samples and tasted comet-like organics inside the little moon. Two more Enceladus flybys are coming up in October, and they may bring the spacecraft even closer to the moon. The Oct. 9 encounter is complimentary to the March one, which was optimized for sampling the plume. The Oct. 31 flyby is similar to this August one, and is again optimized for the optical remote sensing instruments.
The Cassini web page has a mission blog that will follow the fly by, and you can also find images and videos as well.
News Source: NASA
August 7th, 2008 at 12:51 pm
Cassini-Huygens rocks teh casbah!!
Props to all those who made it happen!
How can it be that this 10 years old spacecraft can do all theses different and awesome things like getting as close as 50 km from the surface, going through geysers looking for & finding organics etc…, all this billions of miles away from home whilst some "others" are mere reiterations of 30 years old mission…
August 7th, 2008 at 3:19 pm
It is quite amazing what they've been able to do with this spacecraft. I guess the only thing that would top this would be to fly Cassini close enough (and slow enough) to Saturn's rings to be able to image individual particles making up the rings. (Not that I'm holding my breath on that one).
Kudos to the Cassini team and all those who have gone before.
August 7th, 2008 at 5:20 pm
SOL: NASA is allowed to innovate when it comes to robotic designs.
The same is not true for manned missions. They're still using the same 30 year old ships because to change anything onboard the Shuttles or create a new ship would cause the government to take their funding and people to cry out that their new designs are unsafe.
They can risk anything with robotics, but risk nothing with manned flights.
August 8th, 2008 at 12:40 am
Amazing.
lets see the pictures when they do emerge.
August 8th, 2008 at 12:56 am
Tyler "my man", you know what the government does– It's 'C.Y.A'.
The Cassini Mission, along with the Mars Rovers, is the coolest thing in human history.
When they get ready to pull the plug on Cassini, I think NASA should at least do a plunge thru Cassini's Division, and if it survives that, then plunge it into Saturn's atmosphere.
August 8th, 2008 at 9:24 am
As Dave Scott said from Apollo 15 - "…this is exploration at it's finest!"
Very cool! Can't wait to see what shows up.
Tom
August 8th, 2008 at 10:39 am
how much closer can it get to the surface safely? I would also like to see an extreme close up of saturn's ring system