Monday, January 11, 2016 at 4:00 PM

JILA Auditorium

Carol Raymond, JPL

"Unveiling an Alien World: Dawn at Ceres"

Abstract:

Prior to Dawn’s arrival, the 950-km diameter dwarf planet Ceres was the largest unexplored world in the inner solar system. Ceres was discovered in 1801, the first object identified at a time when many were searching for a ‘missing’ planet between Mars and Jupiter. Ceres is an intriguing planetary body thought to have formed within the first few million years of formation of our solar system. Its density and shape indicate that it retained a much as 30% water by mass. The water likely formed a subsurface ocean early in Ceres’ history, but now is mostly an icy mantle that lies near its surface. Recently, the Herschel Space Observatory observed water vapor coming from Ceres that appeared to be localized to certain longitudes. Having completed its comprehensive investigation of protoplanet Vesta in September of 2012, the Dawn spacecraft arrived at Ceres in March of 2015 to finally pull back the veil on this mysterious world. Dawn has mapped the surface of this icy protoplanet, collecting imaging and spectroscopic data to characterize its geology and composition, and has determined its shape and low-order gravity field. The surface displays a surprising morphologic diversity and the dazzling bright spots have beguiled scientists and the public alike. While pre-Dawn models of Ceres formation and evolution that predicted a subsurface ocean still appear viable, the body is far more complex than such simple models foretold. Preliminary results of Dawn’s exploration of Ceres will be discussed and contrasted with what we learned from Vesta.

Back to Speakers