Astrophysics Seminar: Dr. Jason Hofgartner, NASA Jet Propulsion Lab


Location: zoom

Presently-active Physical Processes on Organic-rich Ocean Worlds

Dr. Jason Hofgartner
NASA Jet Propulsion Lab

Ocean Worlds, icy planetary bodies with subsurface water oceans, are now known to be prevalent in the outer solar system and are high priority targets for planetary science and exploration. The atmospheres and surfaces of Ocean Worlds provide important insights into their histories. Saturn’s Ocean World moon Titan has a 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 will be presented. 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. Eris is a candidate Ocean World and the largest object in the solar system yet to be explored by a spacecraft. It will be argued that Eris, despite an anomalously high albedo of almost unity and solar distance of nearly 100 times that of the Earth, is likely a very active world with ongoing resurfacing.

All interested persons are invited to attend remotely—email for information.