Brett Smith for redOrbit.com Your Universe Online

As the Cassini spacecraft hurtles around Saturn along its continuing mission, NASA announced the fifteen-year anniversary of the probes launch this week.

The $3.3-billion mission lifted off the launch pad on October 15, 1997 and has traveled over 3.8 billion miles since flying past Venus twice and Jupiter once en route to entering orbit around the ringed planet in 2004.

The mission has provided a treasure trove of interplanetary data that it has transmitted from the depths of space back to Earth: 444 gigabytes of scientific data and over 300,000 images. The craft carries several instruments, including a radar mapper, an infrared spectrometer, an ultraviolet spectrograph and a cosmic dust analyzer.

Information culled from these instruments has been used in more than 2,500 published journal reports, including descriptions of ice water plumes on Saturns Enceladus, the hydrocarbon-filled lakes of Titan, and a gigantic storm in Saturns atmosphere.

As Cassini conducts the most in-depth survey of a giant planet to date, the spacecraft has been flying the most complex gravity-assisted trajectory ever attempted, said Cassini program manager Robert Mitchell in a statement. Each flyby of Titan, for example, is like threading the eye of the needle. And weve done it 87 times so far, with accuracies generally within about one mile, and all controlled from Earth about one billion miles away.

Mitchell added that 15 years of flight have had their impact on the craft; however Cassini still performs its daily tasks with precision.

Im proud to say Cassini has accomplished all of this every year on-budget, with relatively few health issues, he said. Cassini is entering middle age, with the associated signs of the passage of years, but its doing remarkably well and doesnt require any major surgery.

Cassini performs a series of maneuvers as it hurtles around Saturn. The flight instructions are sent from NASA and take into account the numerous gravitational fields in Cassinis path and its limited fuel supply, 72 pounds of radioactive plutonium.

According to NASA, the 4,700-pound craft still has a long mission ahead as it cruises though middle age. Saturns trip around the sun takes 29.7 Earth years and Cassini will have a front row seat as the gas giants northern hemisphere passes into spring. It will be the first time scientists observe the changing of Saturns seasons from such close range.

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NASA Celebrates Cassini's 15 Year Anniversary