Transient Features in Hydrocarbon Seas and Dynamic Climate on Saturn's Moon Titan
April 20, 2021 | Virtual
Abstract: Saturn’s moon Titan has an active, global methane cycle with clouds, rain, rivers, lakes, and seas; it is the only world known to presently have a volatile cycle akin to Earth’s water cycle. The discovery and characterization of transient features in Titan's hydrocarbon seas by NASA's Cassini spacecraft will be presented. Anomalously specular radar reflections (ASRR) from Titan’s tropical region observed with the Arecibo Observatory in Puerto Rico were initially interpreted as evidence for liquid surfaces but after the Cassini spacecraft did not observe lakes or seas at those locations, they were unsatisfactorily explained for more than a decade. It will be argued that the ASRR likely originate from paleolakes/paleoseas: i.e., basins that used to be liquid-filled but are now dry due to climatic variability. Titan observations provide "ground-truth" in the search for oceans on exoearths and an important lesson: that identifying liquid surfaces by specular reflections requires a stringent definition of specular, will be discussed.
Date/TimeApril 20, 2021 from 4:30 PM - 5:30 PM
Dr. Jason D. Hofgartner
NASA Jet Propulsion Laboratory
California Institute of Technology