  Interferometric observations of the atmosphere of Titan were performed with
the Submillimeter Array on two nights in February 2004 to investigate the
global average vertical distributions of several molecular species above the
tropopause. Rotational transitions of CO, isomers of HCN, and HC3N were
simultaneously recorded. The abundance of CO is determined to be 51+/-4 ppm,
constant with altitude. The vertical profile of HCN is dependent upon the
assumed temperature but generally increases from 30 ppb at the condensation
altitude (~83 km) to 5 ppm at ~300 km. Further, the central core of the HCN
emission is strong and can be reproduced only if the upper stratospheric
temperature increases with altitude. The isotopic ratios are determined to be
12C/13C=132+/-25 and 14N/15N=94+/-13 assuming the Coustenis & Bezard (1995)
temperature profile. If the Lellouch (1990) temperature profile is assumed the
ratios decrease to 12C/13C=108+/-20 and 14N/15N=72+/-9. The vertical profile of
HC3N is consistent with that derived by Marten et al. (2002).
