Cassini Spacecraft Enters Between Saturn and its Rings

IAS Prelims 2023

NASA’s Cassini spacecraft enters the narrow gap between the planet Saturn and its rings in April 2017. No spacecraft has ever been this close to Saturn before.

The gap between the rings and the top of Saturn’s atmosphere is about 1,500 miles (2,000 kilometers) wide.

The spacecraft zipped through this region at speeds of about 77,000 mph (124,000 kph) relative to the planet, so small particles hitting a sensitive area could potentially have disabled the spacecraft.

The spacecraft is in the process of beaming back science and engineering data collected during its passage, via NASA’s Deep Space Network Goldstone Complex in California’s Mojave Desert.

As it dove through the gap, Cassini came within about 1,900 miles (3,000 kilometers) of Saturn’s cloud tops (where the air pressure is 1 bar — comparable to the atmospheric pressure of Earth at sea level) and within about 200 miles (300 kilometers) of the innermost visible edge of the rings.

Cassini’s next dive through the gap is scheduled in May 2017.

Launched in 1997, Cassini arrived at Saturn in 2004. Data from this first dive will help engineers understand if and how they will need to protect the spacecraft on its future ring-plane crossings. The spacecraft is on a trajectory that will eventually plunge into Saturn’s atmosphere — and end Cassini’s mission — on Sept. 15, 2017.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency.