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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:

Flat spots on Saturn's moon Titan may be the floors of ancient lake beds

Peculiar flat regions on Saturn's moon Titan could be the dry floors of ancient lakes and seas. The suggestion, published June 16 in Nature Communications, may solve a 20-year-old mystery [open, DOI: 10.1038/s41467-020-16663-1] [DX].

[...] "Titan is still currently the only other place in the universe that we know to have liquid on its surface, just like the Earth," says planetary scientist Jason Hofgartner of NASA's Jet Propulsion Laboratory in Pasadena, Calif. But the lakes and seas are concentrated near Titan's poles, not the tropics. The regions where the specular reflections show up are bafflingly dry.

[...] The researchers considered whether rainfall, dunes or dry lake beds could be responsible for the reflections, and found that only lake beds explain the timing and locations of the signals. It does rain on Titan, but not frequently enough to explain the reflections, and Titan's dune fields are in the wrong spots. And the specular reflections come from two specific regions that look like other empty lake basins near Titan's poles (SN: 4/15/19).

[...] So if the reflections come from lost lakes, where did the liquid go? One possibility is that it moved from the equator to the poles as part of a Titan-wide methane cycle (SN: 12/8/17). Another is that the liquid evaporated and was destroyed by sunlight striking Titan's atmosphere.

Related: Titan's Flooded Canyons
Tiny Waves Estimated in Titan's Hydrocarbon Lakes
Extreme Methane Rainstorms Appear to Have a Key Role in Shaping Titan's Icy Surface
Acetylene and Butane Could Form Crystals on Titan

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