After logging 20 years and 4.1 billion miles in space, the Cassini spacecraft last week took the first step in its final mission: a daring 77,000 mph dive between Saturn and its rings of dust, rocks, and
ice. NASA scientists back on Earth had braced for a bumpy ride, expecting to hear pops and cracks as dust particles hit the unmanned probe. But Cassini’s plunge was eerily quiet, suggesting the 1,200-mile gap is virtually devoid of debris. “The region between the rings and Saturn is ‘the big empty,’ apparently,” Cassini project manager Earl Maize tells Space.com. The emptiness was a welcome discovery, as NASA will no longer have to use Cassini’s antenna as a shield against potential debris.
The spacecraft has already performed a second dive; it will do 20 more before running out of fuel and burning up in Saturn’s atmosphere in September. Scientists hope this “Grand Finale” mission will reveal clues about the origins of the planet’s rings and help them learn more about Saturn’s clouds, gravity, and magnetic fields.
