NASA’s Cassini spacecraft to descend into Saturn’s atmosphere



The Cassini spacecraft makes a flyby around Titan, one of Saturn’s moons. The spacecraft is set to plunge into Saturn’s atmosphere early tomorrow morning.

by Tiffany Wong, Aquila News Editor

NASA’s Cassini spacecraft, currently traveling on course to Saturn, will end its 13-year trip around the planet and its moons by descending into the Saturn’s atmosphere early Friday morning.

Researchers at NASA hope to determine whether or not the Saturn’s moons—specifically Enceladus with its subsurface ocean and Titan with its lakes of methane—are habitable. NASA predicts their observation centers will lose contact with the Cassini probe around one minute after its entrance into Saturn’s atmosphere, where the spacecraft will begin to crumble and burn up under the heat of Saturn’s cloud tops.

“When a solid object enters the outer atmosphere of a planet, the outer atmosphere is extremely rarefied. The object is actually moving faster than the average speed of the particles up in the atmosphere, which means the particles can’t get out of the way,” physics and astronomy teacher Dr. Eric Nelson said. “They start building up a pressure wave on the front of the spacecraft. Anybody that’s taken chemistry remembers Boyle’s law, and as the pressure goes up, the temperatures goes up—to the point where you end up with a superheated plasma shockwave in front of the spacecraft.”

Radio signals from the Cassini probe take around 83 minutes to reach Earth, and the spacecraft is predicted to stop transmitting signals at around 3:31 a.m. PST. NASA’s Deep Space Network observatory in Canberra, Australia will receive the Cassini probe’s last messages until the spacecraft’s disintegration, which researchers predict will take around five to six minutes in Saturn’s high atmospheric heat.

NASA first launched the probe in 1997 from Cape Canaveral Air Force Station Space Launch Complex 40 in Cape Canaveral, Florida. The Cassini spacecraft discovered two new moons in Saturn’s system around one month before it entered Saturn’s orbit in July 2004. After mapping and taking pictures of the planet’s moons and rings for four years, researchers decided to bring the Cassini spacecraft closer to Saturn with trips in and out of the gap between the planet and its rings. Its last of 22 such dives, dubbed the “Grand Finale,” would take the probe into the Saturn itself.