Cloudy workshop, 2020, Athens Greece is postponed

Gary Ferland

We are postponing the 2020 Cloudy workshop until the virus is under better control.  We are considering various options including Fall 2020 and Summer 2021.   The workshop newsgroup will be maintained and is a good place to receive updates on our plans.
be safe,

Cloudy workshop, 2020, Athens Greece

Gary Ferland

Cloudy workshop, 2020, Athens Greece 

Registration will soon open for the Cloudy workshop to be held 2020 June 15 to 19 at the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS) in Athens Greece.  The science part of the workshop is described at Join this forum ( to be notified of updates on the workshop.  Instructions for registering and local information about the venue will be posted soon with an announcement to this forum.



Cloudy is a large-scale code that simulates the microphysics of matter exposed to ionizing radiation. It calculates the atomic physics, chemistry, radiation transport, and dynamics problems simultaneously and self-consistently, building from a foundation of individual atomic and molecular processes. The result is a first-principles prediction of the conditions in the material and its observed spectrum.


The workshop will cover observation, theory, and application of Cloudy to a wide variety of astronomical environments.  This includes the theory of diffuse matter and quantitative spectroscopy, the science of using spectra to make physical measurements. We will use Cloudy to simulate such objects as AGB stars, Active Galactic Nuclei, Starburst galaxies, and the intergalactic medium.


The sessions will consist of a mix of textbook study, using Osterbrock & Ferland, “Astrophysics of Gaseous Nebulae and Active Galactic Nuclei”, application of Cloudy to a variety of astrophysical problems, and projects organized by the participants. No prior experience with Cloudy is assumed although some knowledge of spectroscopy and the physics of the interstellar medium is useful.


See these websites for more information:


IAASARS The host institution


The workshop forum to be notified of future developments


The Cloudy user forum has moved!

Gary Ferland


The Cloudy user form has moved to  The content and user list have moved to our new home.  

We set up four separate subgroups.  Main is a place to ask questions or report problems.  Attachments now work, so please include any files needed to understand the question.   Announcements have major announcements about Cloudy.  The results page is where you can post reports of cool results, plots, or journal links.  Finally, the code page is where you can contribute useful scripts or data.  This post is going to the announcements page. 

Please let us know of any problems.  We think we have the permissions set, but there may be work left to do.