My core research centers on the activity and evolution of comets. How are the gases that we see connected to ices in the nucleus? In how far do comets represent left-over building blocks from the disk out of which our planets were formed? In pursuit of these questions I participate in several missions to comets.



The European Rosetta spacecraft will arrive at comet 67P/Churyumov-Gerasimenko in August 2014. I am a member of the OSIRIS science team. This instrument has two cameras that image the nucleus and coma. As a member of the science team, I am involved in the planning and calibration of the camera, and in the scientific interpretation of the images sent to Earth. OSIRIS was re-activated this Spring and is now searching for faint signals of gas produced by the comet.

Deep Impact/EPOXI

The Deep Impact spacecraft delivered an impactor to comet 9P/Tempel 1 in 2005, then continued to comet 103P/Hartley 2. I joined the science team of EPOXI in 2010 and work mostly on images from the Medium Resolution Imager. This camera was specifically designed to investigate the connection between nucleus and coma, with a large field of view and several narrowband filters.

After the Hartley fly by the spacecraft was used as a space telescope, with an instrument suite that was tailored to study comets. It studied comet C/2009 P1 (Garradd), a relatively young comet from the Oort Cloud and was able to measure its rotation period and its CO and CO2 content. Deep Impact observed comet ISON in the spring of 2013.

The spacecraft failed unexpectedly in August 2013.


Stardust collected dust particles from comet 81P/Wild 2, brought those back to Earth, then continued onward to comet 9P/Tempel 1. Stardust-NExT flew by the nucleus in 2011 and imaged the area hit by Deep Impact. I used the Navigation Camera to determine the comet’s dust production rates, to find gas jets, and to connect them geological features on the surface.  

Selected Publications:

  1. Williams, J.L., Li, J.-Y., Bodewits, D., and McLaughlin, S.A.,  NASA Planetary Data System (2012), ‘EPOXI 103P/HARTLEY2 ENCOUNTER - MRI PHOTOMETRY V1.0, DIF-C-MRI-5-EPOXI-HARTLEY2-PHOTOM-V1.0’

  2.   Bodewits, T. L. Farnham, M. F. A’Hearn, and the DIXI team, CBET 3090 (2012), ‘EPOXI observations of Comet 2009/P1 (Garradd)’

  3.   T. L. Farnham, D. Bodewits, J.-Y. Li, J. Ververka, P. Thomas, and M.J.S.             Belton, Icarus, 222, p. 540 (2013), ‘Connections between the Jet Activity and Surface Features on Comet 9P/Tempel 1’

  4.   M.S. Kelley, D.J. Lindler, D. Bodewits, M.F. A’Hearn, C.M. Lisse, L. Kolokolova, J. Kissel, B. Hermalyn, Icarus, 222, 2, p. 624 (2013), ‘A Distribution of Large Particles in the Coma of Comet 103P/Hartley 2’

BElOW: Deep Impact flew within 700 km of 103P/Hartley 2. It discovered that the comet was surrounded by tens of thousands of snow balls.

BElOW: Stardust found several small jets on the sunward side of comet Tempel 1.



BElOW: Rosetta/OSIRIS first sighting of comet 67P/Churymov-Gerasimenko in 2014.