NSF Award
2407709
Titan, Saturn’s largest moon, is considered a possible analogue for studying the processes occurring on primitive, Earth-like planets. Titan has a thick atmosphere, rich in carbon, nitrogen and organic compounds. The unprecedented spatial resolution and sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA) enables the entire Earth-facing hemisphere of Titan to be mapped in only minutes. This research team will elucidate Titan’s high-altitude atmospheric physics and chemistry, to improve our understanding of the key processes responsible for shaping the atmospheres of slowly rotating Earth-like planets throughout the Galaxy. They will promote the uptake of science careers by under-represented minorities via the intern Program for Underrepresented Minorities in Astrophysics (iPUMA). Undergraduates will be recruited to participate in a paid 10-week internship where they will conduct independent research by participating in imaging and analysis of ALMA data on solar system bodies. <br/><br/>The recent discovery of a strongly time-variable thermospheric jet presents a major challenge for theories regarding Titan’s high-altitude atmospheric physics. This project will use ALMA archival data to produce accurate zonal wind fields for Titan's middle/upper atmosphere (in the altitude range 200-1000 km), as a function of latitude and time between 2012-2016. By focusing on species that emit at high-altitudes (HC3N, HCN and HNC), the project focuses on the little-studied region between 500–1000 km that was inaccessible to Cassini CIRS limb-sounding studies. By comparing the observations to output from state-of-the-art general circulation models, the project will investigate the origin of Titan's mysterious thermospheric jet and study the importance of atmospheric waves in the horizontal and vertical transport of angular momentum. By exploiting the wealth of available ALMA archival data, the team will perform an exhaustive, deep search for new, complex organic molecules on Titan, to help elucidate the steps towards biologically relevant compounds in primitive, C and N-rich (exo-) planetary atmospheres.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
