Cassini prepares for dramatic climax to its mission
NASA's Cassini spacecraft recently completed the second of five planned burns designed to maneuver the spacecraft out of Saturn's ring plane, and into a polar orbit. The move is being made in preparation for the final phase of Cassini's mission, which will see the spacecraft perform a series of daring orbits, maximizing the probe's scientific output prior to the mission's termination.
The venerated probe had been operating in Saturn's equatorial orbit since insertion there in Spring 2014, making use of the ring plane to undertake a series of final encounters with the gas giant's eclectic moons.
These close passes have provided scientists at NASA with a wealth of new information regarding the nature of the Saturnian system, but unfortunately, Cassini's operational life is coming to an end, and so mission operators are setting the probe on a new, polar orbit.
The recent maneuver that took place on Jan. 23 was the second in a series of five planned burns, which will harness the gravitational force exuded by Titan to manipulate Cassini's orbital trajectory. At 5:47 p.m. EST on the 23rd, Cassini's main hydrazine engine fired up for a 35-second burst, altering the probe's velocity by 22.3 ft per sec (6.8 m per sec).
The encounter with Titan, which is due to take place on Feb. 1, will have a far greater impact on the spacecraft, altering its velocity by 2,539 ft per sec (774 m per sec). The next transfer burn is scheduled to take place on Mar. 25, setting up another Titan gravity assist on Apr. 4.
The intricate dance between Cassini and Titan is acting as a crescendo leading up to the spacecraft's final act. Once inserted in its polar orbit, Cassini will fly high above Saturn, just beyond the gas giant's F-ring.
The probe will complete 20 of these orbits, before altering its trajectory once more to plunge between the innermost ring and the planet's surface 22 times, before ending its mission by hurtling into Saturn's dense atmosphere on Sep. 15, 2017.