Christopher Stark
University of Maryland
Department of Physics
Box 197
082 Regents Drive
College Park, MD 20742-4111

 

Christopher Stark
NASA Goddard Space Flight Center
Exoplanets and Stellar Astrophysics Laboratory
Code 667
Greenbelt, MD 20771
Phone: (301) 286-7688
Office: Bldg 21, Rm 120

 

Curriculum Vitae

Reference Section

Astronomy/Astrophysics
> 2MASS Catalog
> ADS
> astro-ph
> Debris Disk Database
> Exoplanets Encyclopedia
> Exozodi Simulation Catalog
> gcWeb
> SIMBAD
> VizieR Service

 


One of my simulations imaged with the New Worlds Observer, as it appeared on the cover of the July 6, 2006 issue of Nature.  Read about the simulation here.

Welcome!  I'm a graduate physics student pursuing my Ph.D. at the University of Maryland.  My research is conducted under the advisement of Dr. Marc Kuchner at NASA Goddard Space Flight Center. 

Collisionless Debris Disk Dynamics
I am in the process of investigating the signatures of Earth-like planets in collisionless debris disks.  Debris disk particles lose angular momentum due to Poynting-Robertson (PR) drag and spiral inwards towards their host star.  Along the way, they can get caught in mean-motion resonances with the planet where they stay until they are eventually ejected due to close encounters with the planet, creating a large circumstellar ring structure. 

I have developed a hybrid symplectic integrator for our models and implemented it on the Discover cluster at NASA GSFC. Check out my catalog of debris disk ring structures due to terrestrial-mass planets. A few examples of my simulations are shown below.


      Face-on cloud                 Inclined cloud                 Edge-on cloud                 Face-on cloud
     2 MEarth planet               1 MEarth planet                1 MEarth planet           Jupiter-mass planet

Collisional Debris Disks
I am currently creating an algorithm that will allow us to self-consistently treat resonant gravitational dynamics and collisions in debris disks. This should allow us to accurately model disks like Fomalhaut .

Observations of Debris Disks
I am part of a team observing debris disks with the Keck   Interferometer Nuller We're looking for signs of dust near the habitable zones of other stars, similar to our zodiacal cloud, but much brighter.

dustmap.pro
All of the above images were synthesized using dustmap.pro, an IDL package I wrote to view debris disks from any vantage point--even within!  dustmap.pro produces 2D or 3D density histograms and can synthesize images of dust clouds illuminated by starlight including both scattered light and thermal emission.  It uses scattering and absorption coefficients from Mie theory for astronomical silicate dust and a modified Hong phase function.  You can use it, too--all you need is a set of discrete 3D positions for input.  Download v2.0 of dustmap.pro here

***UPDATE: dustmap.pro has been updated to v2.0. Several new functions have been added, the default imaging mode has been changed from the 3D mode to the 2D mode, and two sample input files have been included with the distribution. See the README.txt file for more information.

To install dustmap.pro, access the directory where you saved the .tgz file and type

tar xvzf dustmap.2.0.tgz

Then check out the README.txt file.  Please let me know if you run across any bugs.

dustmap also works in conjunction with ZODIPIC, which you can find on Marc Kuchner's home page .

Recent Presentations:

  • "Debris Disk Modeling: From Exozodiacal Structures to Collisional Disks," STScI (1/26/09)  PPT
  • "Keck Interferometer Nuller Observations of the 51 Ophiuchi Circumstellar Disk," AAS Meeting (1/7/09)  PPT
  • "Debris Disks -- Theory and Modeling," Exoplanet Forum (5/30/08)  PPT
  • "Modeling Structures in Exozodiacal Clouds," National Capital Area Workshop (12/3/07)  PPT
  • "Debris Disk Structures Induced by Terrestrial-Mass Planets," Spirit of Lyot Meeting (6/03/07), 45th Goddard Memorial Symposium (3/20/07)  Poster
  • "Debris Disk Structures Induced by Terrestrial-Mass Planets," AAS DDA Meeting (5/07/07)  PPT
  • "Debris Disk Structures Induced by Terrestrial-Mass Planets," NASA GSFC Exoplanet Club Meeting (3/1/07) PPT
  • "The cosmic infrared background and the importance of zodiacal light modeling," (Presentation for cosmology class) (05/11/06)  PPT   Paper
  • "Resonant trapping by terrestrial-mass planets in debris disks," American Astronomical Society Meeting (01/12/06)  Poster
  • "Can We Detect an Earth by its Ring?" Nearby Resolved Debris Disk Mini-Workshop   (10/20/05)  PPT
 

Links

Astronomy/Astrophysics
> NASA GSFC Exploration of the Universe Division
> NASA GSFC Exoplanets & Stellar Astrophysics Lab
> Marc Kuchner's Home Page
> GSFC Exoplanet Club
> Keck Observatory
> Keck Interferometer
> Michelson Science Center

Academic
> U. of Maryland
> UMD Dept. of Physics
> UMD Dept. of Astronomy
> U. of Northern Iowa
> UNI Dept. of Physics

Miscellaneous
> Students for Separation of Religion from State