IRAF

IRAF

Original author(s)	National Optical Astronomy Observatory
Developer(s)	IRAF community volunteers
Initial release	1984; 40 years ago (1984)
Stable release	2.18  / 5 April 2024; 7 months ago (5 April 2024)
Repository	github.com/iraf-community/iraf
Operating system	Linux, macOS, FreeBSD, Hurd
Platform	x86-64, AArch64, x86, MIPS architecture, PowerPC, ARMv7, RISC-V, DEC Alpha, x32 ABI, Apple M1, LoongArch
Type	Astronomical Analysis
License	open-source license
Website	https://iraf-community.github.io

IRAF (Image Reduction and Analysis Facility) is a collection of software written at the National Optical Astronomy Observatory (NOAO) geared towards the reduction of astronomical images and spectra in pixel array form. This is primarily data taken from imaging array detectors such as CCDs. It is available for all major operating systems for mainframes and desktop computers. IRAF was designed cross-platform, supporting VMS and UNIX-like operating systems. Use on Microsoft Windows was made possible by Cygwin in earlier versions, and can be today done with the Windows Subsystem for Linux. Today, it is primarily used on macOS and Linux.

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

Functionality available in IRAF includes the calibration of the fluxes and positions of astronomical objects within an image, compensation for sensitivity variations between detector pixels, combination of multiple images or measurement of the redshifts of absorption or emission lines in a spectrum.

While IRAF is still very popular among astronomers, institutional development and maintenance was stopped. IRAF is now maintained as community software.^[1][2]