ALMA observations of Titan's atmospheric chemistry and seasonal variation. Issue Volume 13:Issue S332(2017) (4th September 2018)

• Record Type: Journal Article
• Authors: Cordiner, M. A.; Lai, J. C.; Teanby, N. A.; Nixon, C. A.; Palmer, M. Y.; Charnley, S. B.; Thelen, A. E.; Molter, E. M.; Kisiel, Z.; Vuitton, V.; Irwin, P. G. J.; Mumma, M. J.
• Editors: Cunningham, Maria; Millar, Tom; Aikawa, Yuri
• Is Part Of: Proceedings of the International Astronomical Union. Volume 13:Issue S332(2017)
• Page Start: 95
• Page End: 102
• Publication Date: 2018-09-04
• Subjects: Planets and satellites: individual (Titan), -- line: identification, -- techniques: interferometric, -- techniques: spectroscopic, -- astrochemistry, -- astrobiology; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921317007050
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: Results are presented from our ongoing studies of Titan using ALMA during the period 2012-2015, including a confirmation of the previous detection of vinyl cyanide (C2 H3 CN), as well as the first spatial map for this species on Titan. Simultaneous mapping of HC3 N, CH3 CN and C2 H5 CN reveal characteristic abundance patterns for each species that provide insight into their individual photochemical lifetimes, and help inform our understanding of Titan's unique, time-variable atmospheric chemistry and global circulation. A time-sequence of HC3 N maps covering 38 months reveals a dramatic change in the distribution of this gas consistent with high-altitude photochemical production followed by advection towards the southern (winter) pole, combined with rapid loss in the north after Titan's 2009 seasonal equinox. The 2015 C2 H3 CN and C2 H5 CN maps show abundance peaks in Titan's southern hemisphere, similar to those observed for the short-lived HC3 N molecule. The longer-lived CH3 CN, on the other hand, remains more concentrated in the north.