Touring Saturn's Moon, Enceladus
Posted on: Monday, 30 August 2004, 06:00 CDT
Saturn's moon, Enceladus, was discovered two hundred and fifteen years ago today, but the Cassini probe has targeted this icy world for its lunar tour through the Saturnian system.
Astrobiology Magazine -- Two hundred and fifteen years ago today, Sir William Herschel discovered Saturn's moon Enceladus (499 kilometers, 310 miles across).
A mission goal for Cassini is to determine the composition of moons like Enceladus. Along with most of the other 33 satellites, Enceladus appears to have an icy crust.
Condensed ices give the moons very high albedo (reflection coefficients) but are mottled with darker regions that may be rich in organic chemicals like methane or ammonia.
These building blocks for primitive biochemistry may offer insight into how a similar, but much warmer environment on Earth, might have given rise to primordial life.
Cassini will conduct its four-year orbital mission, circling Saturn 77 times and cruising by more than 50 close encounters (and another dozen or so more-distant encounters) with the planet's moons.
In all, Cassini will aim its instruments at 8 of Saturn's 33 known moons. Cassini has already discovered a few that were unknown from ground observation and an earlier Voyager flyby.
Titan will get the lion's share of attention: 45 close flybys are planned for the giant moon.
Titan will also be the target of the Huygens probe, which will be released by Cassini on Christmas day (Christmas eve in the U.S.) for descent through Titan's atmosphere 3 weeks later.
Titan is of particular interest to scientists because, like Earth, it has an atmosphere that contains nitrogen and organic molecules such as methane.
Some scientists speculate that Titan's chemistry may offer a snapshot of what Earth's chemistry was like before life took hold.
After Cassini releases the Huygens probe, it will spend about 10 exploring several of Saturn's icy satellites. Cassini will make close flybys of Enceladus, Hyperion, Dione and Rhea during this grand lunar tour.
About Cassini-Huygens
Given the enormous distance between Earth and Saturn, it would have been a waste to send a spacecraft to the Saturnian region and only take a few measurements.
Thus, the Cassini orbiter and the Huygens probe are equipped with an array of sophisticated instruments and cameras able to collect images in many varying conditions and light spectra; from visible light to the infrared.
After a seven-year voyage that includes four gravity-assist maneuvers, Cassini entered Saturn's orbit in July of 2004. It will then begin a four-year mission that includes more than 70 orbits around the ringed planet and its moons.
Pointing its various instruments at carefully calculated scientific targets, Cassini will collect detailed data on Saturn, its rings and the 30 known moons orbiting this gas giant.
The information will aid scientists in understanding this complex and fascinating region. Main scientific goals include measuring Saturn's huge magnetosphere, analyzing from up close those stunning rings and studying Saturn's composition and atmosphere.
-----
On the Net:
More science, space, and technology from RedNova
Related Articles
- Cassini Radar Sees Earth-like Features On Saturn's Moon Titan
- Life on Saturn's Moon Titan Unlikely
- Cassini Finds Particles Near Saturn's Moon Enceladus
- European Probe Lands on Saturn's Moon
- Space Probe Relays Data From Saturn's Moon
- European Probe Closes in on Saturn Moon
- The Science Channel Presents an In-Depth, Two-Part Special on NASA's Cassini-Huygens Mission to Saturn, Including Coverage of the Historic Landing on Saturn's Moon Titan
- European-Built Space Probe Begins Descent to Saturn Moon Titan
- Spacecraft Gets Close Look at Saturn's Moon Titan
 |
 |
User Comments (0)
RSS Feeds