There will be a network outage, Sunday, April 26 from 13:00 EDT - Monday April 27 01:00 EDT. All services, web sites, and systems that require access to the internet will be affected by this work.

Marc Kuchner
NASA Goddard Space Flight Center
Exoplanets and Stellar Astrophysics Laboratory

Code 667
Greenbelt, MD 20771
Marc.Kuchner at
CV and Publication List

I'm an astrophysicist; I work on theoretical and observational projects related to directly imaging Extrasolar Planetary Systems.

Disk Detective Logo The Disk Detective citizen science project is scouring the data archive from the WISE all-sky survey to find warm dust around nearby stars: protoplenatary disks and debris disks. Volunteers on this NASA/Zooniverse website have already performed more than 600,000 classifications of WISE sources. Using the power of crowdsourcing, we stand to increase the pool of known debris disks by ~375 and triple the solid angle in clusters of young stars examined with WISE, finding new targets for JWST and exoplanet imaging. For the latest news, see the Disk Detective Blog.
Coronagraph Image Plane The technique of Coronagraphy increases the dynamic range of a telescope so it can see planets without being swamped by the glare from the stars they orbit. Here is an image of Sirius made with a conventional coronagraph. I'm studying the WFIRST mission, which will use a Coronagraph with a Band-Limited Mask to image exoplanets.

Starshade Another potential way to directly image extrasolar planets is with a Starshade. I'm studying some possible mission concepts that will use one spacecraft as a starshade to block the starlight from a telescope on a second spacecraft.
Carbon Planet Imagining New Kinds of Planets can help us decide where and how to look for extrasolar planets. Extrasolar planets are not necessarily like the ones in the solar system; they may have completely different chemistries, like Water Planets or Carbon Planets . Life on a carbon planet would be through-the-looking-glass. The processes of burning and metabolism on Earth are oxidation (combining things with oxygen); on a carbon planet, these processes would probably be replaced by reduction (combining things with carbon). Artist Lynette Cook created this image of a Carbon Planet.

Vega Disk Model Our Sun sports a handsome disk of zodiacal dust, full of structures due to the dynamical effects of planets. Here is an explanation, with illustrations, of how planets on low-eccentricity orbits make rings and wakes in an optically thin circumstellar dust cloud. Zodiacal dust around other stars is called Exozodiacal Dust.
Debris Disk Animation

This animation shows what a few-jupiter-mass planet on an eccentric orbit (e=0.6) can do to a dust cloud. The solar system doesn't have any such planets, but extrasolar planetary systems often do. Millimeter maps of the debris around Vega show two blobs of emission at different distances from the star which may be the same phenomenon. However, this disk and other Debris Disks may be much more complicated than the solar dust cloud.

Animation of Dust Orbiting Vega
Press Release on Millimeter Maps of Vega
Powerpoint Talk on Resonant Signatures in Debris Disks

Image of Dusty Rings made with ZODIPIC Here is the ZODIPIC package, an IDL program for synthesizing images of exozodiacal clouds. It also has enough tweakable parameters to serve as a general-purpose modeling tool for optically-thin disks. To use it, you may download zodipic to your idl directory. Save the file as "zodipic.2.1.tar". Then type

tar xvf zodipic.2.1.tar

to unpack the files (total about 57K). The README.zodipic file describes how to run the code. The picture above was made by running zodipic twice:

zodipic, fnu1, 1, 0.5, inclination=60, positionangle=-10, ring=1, blob=1, pixnum=256, /noiterate, /nofan
zodipic, fnu2, 1, 0.5, inclination=60, positionangle=-10, ring=1, blob=1, pixnum=256, /noiterate, /nofan, radring=0.72, earthlong=100

NEW! Zodipic Version 2.1.
Includes dust with real optical constants, user-specified dust maps, and more!
See also

Kuchner, M. J., & Serabyn, E. 2001, submitted to ApJ
Powerpoint Talk on ZODIPIC

Telescope at Mt. Palomar On some cloudy nights, I like to write Observing Manuals like this guide to the Palomar 60" CCD Camera.

And here are some of my other Powerpoint Talks

Dude With Diploma I am lucky to work with some talented Graduate Students and Postdocs:

Chris Stark Graduate Student, U. Maryland Physics Dept. Now a NASA Postdoctoral Program fellow at Goddard Space Flight Center
Daniel Jontof-Hutter Grad. Student, U.M.D. Astronomy
Justin Crepp Graduate Student, U. Florida, Astronomy Dept. Now an assistant professor at the University of Natre Dame.
Erika Nesvold Graduate Student, University of Maryland Baltimore County Physics Dept.
Aki Roberge NPP Postdoctoral Fellow, GSFC. Now a staff scientist at GSFC.
Ruslan Belikov NPP Postdoctoral Fellow, GSFC. Now a staff scientist at NASA Ames.
Hannah Jang-Condell Michelson Postdoctoral Fellow, GSFC/UMD. Now an assistant professor at the University of Wyoming.
John Wisniewski NPP Postdoctoral Fellow, GSFC. Now an assistant professor at the University of Oklahoma.
John Debes NPP postdoctoral fellow, GSFC. Now a staff scientist at STScI.
Thayne Currie NPP postdoctoral fellow, GSFC. Now a postdoctoral fellow at the University of Toronto.
Margaret Pan NPP postdoctoral fellow, GSFC.

Artist's Concept of Planetary System If you are in the DC area, please stop by and give a talk at the Goddard Exoplanets Club. We meet on Tuesdays at 11:30am at Goddard in Building 34, Room E215.
Here are some possibly useful Astronomy Links:

Q&A With Astronomy Magazine
Princeton Astronomy Webmail
General Astrophysics with TPF Workshop
General Astrophysics and Comparative Planetology White Paper
Aspen Conference on Planet Formation and Detection February 6-12, 2005
JPL Docushare
Princeton Seminar Series on Extrasolar Planets and Astrobiology
Paw Points
Database of Observational Mishaps
Statistical Consulting Center for Astronomy
Cosmic Dust
General Astrophysics with TPF Workshop
Synchrotron emission from extrasolar planets.
General Astrophysics and Comparative Planetology White Paper
Caltech Ge 167
CfA Star and Planet Formation Journal Club
Astronomy Meetings
CDS 270
Exploring Neighboring Planetary Systems
Harvard Extrasolar Planets Site
California/Carnegie Extrasolar Planets Site
Astrophysics Data System
Caltech Astronomy Department
Astronomical Pronunciation Guide
Simbad astronomical database
Skyview virtual telescope
RECONS Research Consortium on Nearby Stars
astro-ph Preprint Server
Division of Dynamical Astronomy
ExNPS Exploring Neighboring Planetary Systems site at JPL
Protostars and Planets IV
Astrobiology Office at NASA Ames Research Center.
NED NASA/IPAC Extragalactic Database.
The Large Binocular Telescope
The Submillimeter Array
Atacama Large Millimeter Array
Harvard College Observatory Tennis Club
Did you know that Queen guitarist Brian May used to study zodiacal dust?

NASA Logo, National Aeronautics and Space Administration