title: The Chemical Composition of Comets	

authors: Steven B. Charnley			

Astrochemistry Laboratory, Solar System Exploration Division, Code 691, Science and Exploration Directorate, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
 
abstract:
 I will summarize what is currently known of the chemistry of comets.
Compositional studies, especially of organic molecules, isotopologues, and ortho-para ratios can provide important clues as to their origins, and to their possible role in providing water and biomolecules to the early Earth.


Ehrenfreund, P. & Charnley, S.B. (2000), Annu. Rev. Astron. Astrophys.,  38, 429
Mumma, M. J. & Charnley, S.B. (2011), Annu. Rev. Astron. Astrophys.,   49, 471.