Megan M. Kiminki

(formerly Megan M. Bagley)

Graduate Student

Department of Astronomy / Steward Observatory
University of Arizona
A picture of teddy-bear cholla. Cactus in bloom in northwest Tucson. Hubble Space Telescope image of the HH 666 protostellar jet. Observing at the Magellan Telescopes. The Magellan telescopes in Chile. Saguaro in Sabino Canyon.

How To Install IRAF


With the advent of v2.16, installing IRAF has become significantly easier. These instructions have worked for installations on Mac OS X and multiple Linux systems (Fedora and Ubuntu). They were most recently verified in June 2017.

  1. Download IRAF from here. I recommend the "Combo 32/64-bit" version appropriate for your operating system: most of IRAF has been updated to 64-bit, but there are a few old packages that work better (or only) in 32-bit.

  2. Create an IRAF directory, typically /iraf/iraf, and unpack the tarball there.

    i.e., with tar -xvzf iraf-whatever.tar.gz

  3. Make sure you're working in a tcsh environment (all my terminals are in bash by default); the IRAF installation will fail in bash.. Type tcsh in a terminal to get into tcsh.

  4. Define the $iraf variable in your environment. I have always done this by adding the following line to my .tcshrc file:

    setenv IRAF "/iraf/iraf/"

    You'll then need to run the .tcshrc file (source ~/.tcshrc), repoen a terminal, or re-enter tcsh to make sure the variable is set.

    For good measure, I put the equivalent line in my .bashrc file:

    export IRAF="/iraf/iraf/"

  5. On Linux or older Mac OS X systems, run the installation script with:

    sudo /iraf/iraf/install --system

    (The --system flag means it does the installation for everyone on the computer, not just you.)

    On Mac OS X 10.11 or newer, run the installation script with:

    sudo /iraf/iraf/install and answer "no" to the first prompt.

    (Mac's "System Integrity Protection" will absolutely refuse, even with sudo, to allow the symbolic link in /usr/include/ that is needed for a system-wide installation.)

    On all operating systems, of the default answers to the other install prompts should be fine.

  6. Install xgterm, which now helpfully comes in the same tarball as IRAF. All you have to do is link the executable to somewhere in your $PATH.

    cd /usr/local/bin [or equivalent location]

    sudo ln -s /iraf/iraf/vendor/x11iraf/bin.macintel/xgterm . [or bin.linux as appropriate]

  7. Check that it works by doing mkiraf wherever you want your home IRAF stuff to be. Edit your login.cl preferences, etc. and try opening an xgterm and starting IRAF.

  8. Add desired external packages (also much easier than it used to be). Go to /iraf/iraf/extern/ and follow the instructions in the README file, executing:

    sudo ./configure

    sudo make check [to list the available packages]

    sudo make packagename [e.g., sudo make stsdas]

Good luck! I've also found this site to be helpful with troubleshooting IRAF installations.