Thursday, June 22, 2017
Cassini - IN PROGRESS: Orbit 278 - UNIVERSE
During this orbit, Cassini’s Radio Science Subsystem (RSS) performs the fourth of six radio occultations of Saturn’s ring system and runs a gravity experiment to study Saturn's gravitational field in the highest possible detail. The experiment seeks to measure how spherical Saturn’s gravity field is, and to help scientists measure the mass of Saturn’s rings, a figure that is not precisely known.
During the radio experiments, Cassini’s Cosmic Dust Analyzer (CDA) scoops up and analyzes small ring particles to help determine the age of Saturn’s rings. Interplanetary meteoroids bombard Saturn’s main rings, depositing silicates, organics, and metals in the ring particles. The more of those contaminants the CDA finds, the older Saturn’s rings probably are.
Next Cassini’s Visible and Infrared Mapping Spectrometer (VIMS) maps Saturn’s southern hemisphere at some of the highest resolutions of the mission. The instrument looks for changes in winds, cloud structures and perhaps changes in atmospheric chemistry as the rate of atmospheric upwelling changes with seasons.
During this orbit, Cassini gets within 2,120 miles (3,410 kilometers) of Saturn’s 1-bar level. Cassini also passes within 2,670 miles (4,300 kilometers) of the inner edge of Saturn’s D ring.