FITS Data Format

FITS stands for `Flexible Image Transport System' and is the standard astronomical data format endorsed by both NASA and the IAU. FITS is much more than an image format (such as JPG or GIF) and is primarily designed to store scientific data sets consisting of multi-dimensional arrays (1-D spectra, 2-D images or 3-D data cubes) and 2-dimensional tables containing rows and columns of data. See the overview of the FITS format and the FITS Support Office for more general information about FITS.


  • HEASARC FITS conventions - recommended usage for high-energy astrophysics data from the HEASARC FITS Working Group.
  • fv - graphical FITS file viewer and editor (FITS images and tables)
  • SAOImage ds9 - astronomical visualization application from SAO
  • CFITSIO - C and Fortran library for reading and writing FITS files
    • CCfits - object oriented C++ interface to CFITSIO
    • Perl interface to CFITSIO
  • Java FITS library that provides efficient I/O for FITS images and binary tables.
  • FITS Utils - portable set of utility programs to manipulate FITS files
  • FTOOLS - large set of programs for analyzing data in FITS format including:
    • fverify - verify that a file conforms to the FITS Standard. (A standalone version called fitsverify is also available).
    • fcopy - powerful program to selectively copy parts of FITS file to a new file
    • ftlist - print the contents of FITS headers, images, and tables
  • Sample FITS files produced by the HEASARC

Page Author: William Pence

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Last modified: Friday, 04-Mar-2011 11:18:26 EST

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