Last adventure ahead for NASA’s Cassini spacecraft at Saturn
NASA’s Cassini spacecraft, which orbits Saturn, took a picture of Earth from between Saturn’s rings – with Earth’s moon doing a bit of photobombing. The part of Earth facing toward Cassini at the time was the southern Atlantic Ocean. Titan’s gravity will reach out and pull Cassini onto a new path, downward into the narrow gap between Saturn and its innermost ring, where no human artifact has ever gone.
On April 12, as the Sun was blocked by the disk of Saturn the Cassini spacecraft camera looked toward the inner Solar System and the gas giant’s backlit rings. The craft is scheduled to begin its “Grand Finale” dives shortly, in which it will fly recklessly through Saturn’s rings a total of 22 times until, on its final approach, it flies directly into the planet itself.
While another pass at Titan (the craft’s 127th) will provide more details about the moon, and perhaps even find its “magic island“, the visit serves another objective: The close proximity to Titan’s gravity will warp Cassini’s orbit slightly, bringing it from outside the planet’s rings to just inside.
Although Lunine and colleagues have not shown that life exists on one of Saturn’s moons, the researchers say it’s enough to warrant another mission to Enceladus.
“I wouldn’t be a bit surprised if some of the discoveries we make with Cassini might be the very best of the mission”, said Linda Spilker, the mission’s project scientist. The probe will plunge beneath the rings and through the gap separating Saturn from its innermost ring. Cassini recorded what appeared to be images of islands appearing and then disappearing in Ligeia Mare. Cassini’s fuel tank is practically empty, so with little left to lose, NASA has opted for a risky, but science-rich grand finale. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate, Washington.
Cassini also will study Saturn’s atmosphere and take measurements to determine the size of the planet’s rocky core.
“Most of us would be excited with any life”, said Mary Voytek, an astrobiology senior scientist for NASA.
The spacecraft will dive in between Saturn and its rings to study its composition before falling into planet’s atmosphere.
To Cassini will go the credit for discovering what many astronomers think is the most likely place to find evidence of life beyond Earth.
“We now know that Enceladus has nearly all of the ingredients that you would need to support life as we know it on Earth”, she said at a NASA news conference.