Artist's rendition of the T-115 flyby.

Artist's rendition of the T-115 flyby.

Titan Flyby T-115: Last Close Comparison of Titan’s North and South Hemispheres

This flyby is, scientifically speaking, one of the two most important Titan observations for the composite infrared spectrometer (CIRS) instrument during this phase of Cassini's mission. CIRS will perform limb mapping on both of the hazy moon's north and south limbs during this flyby, which will provide a comparison and contrast between the spring (north) and fall (south) hemispheres. Rapid changes in atmospheric circulation are occurring in both hemispheres that have planetary scientists riveted to see what will happen next.

Purple Haze
Encircled in purple stratospheric haze, Titan appears as a softly glowing sphere in this colorized image taken one day after Cassini's first flyby of the moon on July 2, 2004.

CIRS will map the south limb (at 73 degrees south latitude) on the inbound leg of the flyby, and the north limb (at 57 degrees north latitude) on the outbound leg.

Limb mapping provides a measure of how the gas and aerosol abundances in Titan's atmosphere vary with altitude. CIRS will also measure temperature profiles, and it potentially could infer the locations of cloud layers.