Mapping Titan...

These infrared views of Titan peer through the gloom
NASA/JPL-Caltech/Stéphane Le Mouélic, University of Nantes, Virginia Pasek, University of Arizona

Topics: Astrophysics, Cassini, Exoplanets, Moon, Space Exploration

Slowly but surely, the surface of Saturn’s strange moon Titan is being revealed. Researchers have made the first map of the geology of Titan’s entire surface, and it will eventually help us figure out what the climate is like there.

Titan’s atmosphere is full of a thick, orange haze that blocks visible light from reaching the surface, making it difficult for spacecraft to take pictures. NASA’s Cassini spacecraft, which orbited Saturn from 2004 to 2017, took radar and infrared data of Titan’s surface, giving researchers a hint of the terrain below.

Rosaly Lopes at NASA’s Jet Propulsion Laboratory in California and her colleagues assembled those observations and placed each area, or unit, into one of six categories: lakes, craters, dunes, plains, hummocky terrain – meaning hills and mountains – and labyrinth, which looks like heavily eroded plateaus. They then made a map of where each of those terrains exists on Titan’s surface.

We have the first full map of the weird surface features of Titan
Leah Crane, New Scientist

Dénouement...

NASA's Cassini spacecraft flew through the plumes of Enceladus' geysers several times and gathered information about the particles that may foster life on Saturn's small frigid moon.
Credit: NASA/JPL

Topics: Astronomy, Astrophysics, Cassini, NASA, Space Exploration

For Mildred D. Goodwin, September 15, 1925 - May 7, 2009. Happy birthday, mom. As far as this serendipity, I'd like to think she would have enjoyed it.

Friday morning (Sept. 15), Cassini will complete the orbital pirouettes of its seven-year Solstice Mission and complete a self-destructing descent into Saturn's atmosphere. This fierce ending is dramatic for a purpose: It will prevent Earth microbes from contaminating Saturn's nearby moons.

When NASA's Cassini spacecraft completed its first tour of Saturn in 2008, the mission team had to decide what would come next. [Cassini's Saturn Crash 2017: How to Watch Its 'Grand Finale']

Cassini could have parted ways with the ringed planet. In 2009, studies showed that Cassini had enough fuel to reach Uranus or Neptune. Cassini could have traveled in the other direction, toward Jupiter, or it could have been sent to visit an assembly of asteroids known as the Centaurs in the outer limits of the solar system.

Instead, scientists chose to continue making discoveries about Saturn and its moons — first through a two-year extended mission known as the Cassini Equinox Mission, and then with a second extension in 2010 that would bring the spacecraft to the very limit of the fuel it carried. That made it clear that Cassini's third mission, the Solstice Mission, would be how the spacecraft would end its career. It was during these missions that scientists discovered that two of Saturn's moons, Titan and Enceladus, showed signs that they were well suited to life. But why the fiery plummet?

"The spacecraft will burn up and disintegrate like a meteor in the upper atmosphere of Saturn," Preston Dyches, of NASA's Jet Propulsion Laboratory (JPL), told Space.com via email. "This was determined to be the best way to ensure the safe disposal of the spacecraft, so that there would be no chance of future contamination of Enceladus by any hardy microbes that might have stowed away on board all these years."

Why the Cassini Mission to Saturn Must End in a Fiery Dive, Doris Elin Salazar, Space.com Staff Writer