IRAF

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IRAF
Developed by	NOAO
Latest release	2.14 / 14 January 2008
OS	Cross-platform
Genre	Astronomical Analysis
Website	http://iraf.noao.edu

IRAF stands for the Image Reduction and Analysis Facility. It is a huge collection of software written by astronomers and by programmers at the National Optical Astronomy Observatory (NOAO). It is geared towards the reduction of astronomical images in pixel array form, that is, data taken from imaging array detectors such as CCDs.

It is available for all major operating systems for Mainframes and Desktop computers. Although written for UNIX-like operating systems, use on Microsoft Windows is made possible by Cygwin. It is also available for several Linux distributions.

Data taken with array detectors on single-dish telescopes is generally analyzed using IRAF, whereas AIPS or miriad are used for data taken using aperture synthesis arrays.

IRAF commands (known as tasks) are organized into package structures. Additional packages may be added to IRAF. There are many packages available by NOAO and external developers often focusing on a particular branch of research or facility. Of particular note are the STSDAS and TABLES packages by the STScI.

The licensing status of IRAF is conflicted, with different parts of the code under different licenses. Most notably, the graphics infrastructure is under a non-free software license, which does not permit redistribution without permission. As this code is tightly integrated into IRAF, the package as a whole is non-redistributable and therefore non-free. NOAO seems to have made no effort to clarify this situation, and efforts to package the software for drop-in installation in GNU/Linux systems have lapsed. ^[1]