In June 2004, NASA’s Cassini-Huygens spacecraft will reach its ultimate destination: the Saturn system. http://www.jplnet.com/art/craft.html

Cassini has been en route to Saturn for over six years. It was launched on October 15, 1997 aboard a Titan IV-Centaur rocket. http://www-pao.ksc.nasa.gov/kscpao/images/large/97pc1547.jpg

On January 15, 2001, 17 days after its closest approach to Jupiter, Cassini looked back to see the giant planet as a thinning crescent. http://saturn.jpl.nasa.gov/cgibin/gs2.cgi?path=../multimedia/images/jupiter-flyby/images/imagead_010531.jpg&type=image

http://photojournal.jpl.nasa.gov/catalog/PIA04913 This image was composed from exposures taken by Cassini's narrow angle camera on Nov. 9, 2003, from a distance of 111.4 million kilometers (69.2 million miles). New features such as intricate cloud patterns and small moons near the rings should become visible over the next several months as the spacecraft speeds toward its destination. Cassini compiled this image of Saturn in November 2003, from a distance of 111.4 million km (69.2 million miles).

At that time, Cassini was not yet close enough to capture the clarity of this ultraviolet image taken by Hubble. Cassini photo. http://saturn.jpl.nasa.gov/index.cfm Hubble ultraviolet image.

As Cassini approaches Saturn, however, it sends back increasingly detailed images. Astronomers watched two storms merge in Saturn’s southern hemisphere from February to March, 2004. http://saturn.jpl.nasa.gov/cgibin/gs2.cgi?path=../multimedia/images/saturn/images/PIA05386.jpg&type=image

Intricate cloud patterns and small moons near the rings will become visible as the spacecraft speeds toward its destination. http://ringmaster.arc.nasa.gov/saturn/voyager/voyager2.html (this image of Saturn’s rings was taken by Voyager 2 in 1981) http://photojournal.jpl.nasa.gov/catalog/PIA04913

On June 11, 2004, Cassini will enter the Saturn system with a flyby of Phoebe, an outer moon. http://www.the-planet-saturn.com/nasa-artwork.html This is a narrow angle field-of-view artist's rendering from the bottom of a large ice crevasse on the surface of Phoebe, the least known of all the Saturnian satellites. By David Seal http://saturn.jpl.nasa.gov/operations/approach.cfm The few images we have of Phoebe are in essence a bunch of black and white dots arranged in a circular shape. In spite of their low resolution, existing images supplied the science community with clues on a moon simply too small and too far to be studied from Earth.

Cassini will deploy its braking system and be captured into Saturn’s orbit on July 1, 2004. http://www.nasm.si.edu/ceps/etp/saturn/satmoons.html Dione is in foreground, Tethys and Mimas to the right of Saturn, Enceladus and Rhea off Saturn's rings to the left, and Titan at top right.

Cassini can "see" in wavelengths the human eye cannot, and "feel" magnetic fields and tiny dust particles no human hand could detect. http://saturn.jpl.nasa.gov/spacecraft/index.cfm

The orbiter will provide information on Saturn’s planetary structure and rings, as well as temperature, winds, clouds, magnetic fields and lightning. http://saturn.jpl.nasa.gov/overview/mission.cfm 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. http://saturn.jpl.nasa.gov/cgibin/gs2.cgi?path=../multimedia/images/saturn/images/image17.jpg&type=image http://www.carleton.ca/~tpatters/teaching/climatechange/solar/saturn2.html (image of Saturn winds, center)

Cassini will also study Saturn’s numerous moons and "icy satellites." http://saturn.jpl.nasa.gov/cgibin/gs2.cgi?path=../multimedia/images/saturn/images/image18.jpg&type=image This computer rendering shows the surface of Rhea, Saturn's second largest satellite behind Titan. Like Dione and Iapetus, there is a noticeable difference between the two hemispheres of the satellite. Rhea is a densely cratered satellite, and this image shows two of the most prominent craters, Izanagi (the larger) and Izanami (the smaller), which partially overlap. These craters are well into the southern hemisphere. Saturn is seen on the horizon, and a small meteor is seen striking the surface inside the Izanagi crater.

Scientists will use this information to understand the nature and environment of Saturn during its formation and early evolution. http://rst.gsfc.nasa.gov/Sect20/A11.html A recent image, made from data detected at 1.3 mm by a French radio telescope, may have caught the formation of two large clots of matter likely to eventually contract into giant planets. These occur in the ring around the central star Vega, 25 light years away (in the Constellation Lyra). Here is an image based on observations made by D. Wilner and D. Aguilar of Harvard's Smithsonian Center for Astrophysics. (Note: this image has been enhanced artificially as an artist's rendition.)

http://images. google. com/imgres. imgurl=solarsystem. dlr http://images.google.com/imgres?imgurl=solarsystem.dlr.de/PG/cassini/images/cassini_huygens_separation.JPG&imgrefurl=http://solarsystem.dlr.de/PG/cassini/mission/huygens.shtml&hl=en&h=960&w=1280&start=1&prev=/images%3Fq%3Dcassini%2Bhuygens%2Bseparation%26svnum%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8 In December 2004, the Huygens probe will separate from Cassini and begin its 22-day journey to Titan, Saturn’s largest moon.

On January 14, 2005, the probe will descend through Titan's murky atmosphere and land on the surface about two and half hours later. http://saturn.jpl.nasa.gov/cassini/images/slides/slide12.html http://saturn.jpl.nasa.gov/operations/index.cfm

Unlike the Mars Rovers, the Huygens probe will collect data during its descent. We don’t know if it will survive the landing on Titan. http://observe.arc.nasa.gov/nasa/gallery/image_gallery/solar_system/graphics/huygens.jpg

The probe's instruments will directly sample Titan’s atmosphere and attempt to obtain images of the surface as it descends. http://saturn.jpl.nasa.gov/cassini/images/slides/slide17.html The probe has a diameter of 2.7 meters and a mass of nearly 350 kg. It contains a heat shield, parachute package, engineering equipment including batteries, and several scientific sensors to measure properties of Titan's atmosphere and surface. The probe consists of an Entry Assembly which performs thermal and deceleration control during entry into the atmosphere of Titan. The Entry Assembly will be jettisoned after entry, releasing a Descent Module, comprising an aluminum shell and inner structure containing all the science experiments and engineering subsystems. The Descent Module also includes the parachute used in the descent through the atmosphere and the spin control device which controls the rotation of the probe during descent. (P-42810AAC)

Though the Huygens mission will last only a few hours, Cassini’s four-year exploration will entail over 70 orbits around the ringed planet and its moons. http://saturn.jpl.nasa.gov/operations/saturn-arrival.cfm http://saturn.jpl.nasa.gov/cgibin/gs2.cgi?path=../multimedia/images/artwork/images/cassini_saturn.jpg&type=image