Last Cassini Flyby Around Enceladus

This Saturday, November 21, the Cassini spacecraft will perform its last flyby of Saturn's moon Enceladus, before the planet enters its winter season. Once that happens, darkness will blanket the moon for several years, and its doubtful that the space probe, already in its mission-extension period, will last until the next spring, experts at the Jet Propulsion Laboratory announce. The JPL is based at the California Institute of Technology (Caltech), in Pasadena, California, and is operated by NASA.

The most interesting aspect of Enceladus, and the one on which scientists will focus the most during the new flyby, is related to its “tiger stripes,” a number of fissures that exist at its south pole. They are extremely important towards understanding the inner structure of the celestial body, because they constantly emit spews of ice and water vapors. This hints at a possible underground ocean of liquid water, concealed under a thick layer of permanent ice. There are researchers and astrobiologists who say that the ocean may even have sufficient water to allow for the development of primordial life.

The stripes throw their vapors and ices several miles above the surface of the Saturnian moon, which means that, if Cassini is in the correct position, it could view the jets backlit by the Sun, which would allow the robotic observer to see the formations with its spectrometers. This type of analysis allows for the components of the plumes to be examined individually, and for their concentrations to be established as well. During the new flyby, the southern part of the Saturn-facing hemisphere will also be imaged in higher detail, the JPL team announces.

“The flyby, which is sometimes called 'E8' because it is the eighth targeted flyby of Enceladus, is scheduled for Saturday, November 21 UTC, which is the evening of Friday, November 20 in US time zones. Cassini team members expect to fly the spacecraft to within about 1,600 kilometers (1,000 miles) of the moon's surface, at around 82 degrees south latitude. This will be a more distant flyby than the one on November 2, when Cassini flew about 100 kilometers (60 miles) above the surface,” a press release on the lab's website reveals.