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Timeline of Cassini–Huygens

NASA's Cassini Spacecraft Ends Its Historic Exploration of Saturn

Telemetry received during the plunge indicates that, as expected, Cassini entered Saturn's atmosphere with its thrusters firing to maintain stability, as it sent back a unique final set of science observations. Loss of contact with the Cassini spacecraft occurred at 7:55 a.m. EDT (4:55 a.m. PDT), with the signal received by NASA's Deep Space Network antenna complex in Canberra, Australia.

[...] As planned, data from eight of Cassini's science instruments was beamed back to Earth. Mission scientists will examine the spacecraft's final observations in the coming weeks for new insights about Saturn, including hints about the planet's formation and evolution, and processes occurring in its atmosphere.

[...] Cassini launched in 1997 from Cape Canaveral Air Force Station in Florida and arrived at Saturn in 2004. NASA extended its mission twice – first for two years, and then for seven more. The second mission extension provided dozens of flybys of the planet's icy moons, using the spacecraft's remaining rocket propellant along the way. Cassini finished its tour of the Saturn system with its Grand Finale, capped by Friday's intentional plunge into the planet to ensure Saturn's moons – particularly Enceladus, with its subsurface ocean and signs of hydrothermal activity – remain pristine for future exploration.

Farewell, Cassini: a 20 year mission to Saturn comes to a life-protecting end

During the Jovian flyby, Cassini performed scientific observations of the planet, showing that Jupiter's cloud belts were areas of "net-rising atmospheric motion."

This observation contradicted previous hypotheses about Jupiter's dark and light belts and served to highlight differences in planetary weather systems.

During the flyby, Cassini was also able to study Jupiter's thin ring system, revealing that Jupiter's rings were composed of irregularly shaped particles that likely originated as ejecta from micrometeorite impacts with the moons Metis and Adrastea.

Cassini: The legend and legacy of one of NASA's most prolific missions

Previously:

takyon writes:

Cosmic ravioli and spaetzle

The small inner moons of Saturn look like giant ravioli and spaetzle. Their spectacular shape has been revealed by the Cassini spacecraft. For the first time, researchers of the University of Bern show how these moons were formed. The peculiar shapes are a natural outcome of merging collisions among similar-sized little moons as computer simulations demonstrate.

[...] Based on the current orbit of the moons and their orbital environment, the researchers were able to estimate that the impact velocities were of the order of a few 10 m/s. Simulating collisions in this range for various impact angles, they obtained various stable shapes similar to ravioli and spaetzle, but only for low impact angles. "If the impact angle is bigger than ten degrees, the resulting shapes are not stable anymore," says Adrien Leleu. Any duck-shaped object like comet [67P/Churyumov–Gerasimenko] would fall apart because of Saturn's tides. "That is why Saturn's small moons look very different to comets that often have bilobed shapes," explains Martin Jutzi.

Also at Scientific American.

The peculiar shapes of Saturn's small inner moons as evidence of mergers of similar-sized moonlets (DOI: 10.1038/s41550-018-0471-7) (DX)

Related: Cassini Captures Best Ever Images of Saturn's Tiny Moon Pan
Cassini's Final Flyby of Atlas
Cassini Spacecraft Post-Mortem

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