		Last revised 1995 August 9 1700 GMT



Preface



This Flexible Image Transport System (FITS) information is

updated periodically by the FITS Support Office, operated under the 

guidance of the Astrophysics Data Facility at the NASA Goddard

Space Flight Center. It provides a brief description of FITS and

information on software and documentation, discusses some topics that

have appeared on the Usenet newsgroup sci.astro.fits, and answers some

questions on FITS frequently received by the FITS Support Office. 



Substantive changes this revision:



o	Information on Blocking Agreement



o	Information on List of Registered extensions



o	Note that the instructions for the FPCT discuss its

	capabilities and limitations 



o	Note that FITS Support Office software to list headers is in 	

	ANSI C



Revisions made 1995 June 16: 



o	Information on IDL Astronomy User's Library



o	FITS Support now part of xv3.10a (replaces unsupported 

	xv 3.0 modifications)



o	ViewFITS for (OS/2) no longer listed - access and support 

	unavailable (not to be confused with FITSview for Windows,

	which is very much available) 



o	New URL information for GraphicConverter for Macintosh





Table of Contents



Preface

Recent Revisions

Table of Contents

1 Introduction

 1.1 What FITS Is 

 1.2 How FITS Evolves

 1.3 What FITS Is Not 

2 FITS Documents

 2.1 Published Papers

 2.2 Binary Tables

 2.3 User's Guide

 2.4 NOST Definition of FITS

  2.4.1 Version 1.0

  2.4.2 Proposed Revision on Units Specification

 2.5 Floating Point Agreement

 2.6 Blocking Agreement

 2.7 List of Registered Extensions

 2.8 World Coordinates

 2.9 Proposed Conventions

3 Software and Sample Data

 3.1 FITS Support Office 

  3.1.1 FITS Product Conformance Tester with Instructions

  3.1.2 Header Lister 

  3.1.3 Error Test Files

 3.2 HEASARC

  3.2.1 FITSIO

  3.2.2 FTOOLS

  3.2.3 VERIFITS

 3.3 ADC FITS Table Browser

 3.4 FITS I/O software in IDL

 3.5 Display of FITS Image Files

  3.5.1 Major Astronomical Image Analysis Packages

  3.5.2 pbm+

  3.5.3 IMDISP (IBM/PC)

  3.5.4 SAOimage

  3.5.5 Applications with XV 

  3.5.6 FITS and the Macintosh 

  3.5.7 FITSview (Windows)

 3.6 World Coordinates 

4 On-line Information Sources

 4.1 FITS Support Office

 4.2 HEASARC

 4.3 NRAO

 4.4 HEAFITS exploder

5. Contributors (non-exhaustive list)

6. FITS Support Services from GSFC



1 Introduction

 

 1.1 What FITS Is 



FITS (Flexible Image Transport System) is a data format designed to

provide a means for convenient exchange of astronomical data between

installations whose standard internal formats and hardware differ. A

FITS file is composed of a sequence of Header Data Units (HDUs). The

header consists of keyword=value statements, which describe the format

and organization of the data in the HDU and may also provide

additional information, for example, about instrument status or the

history of the data.  The data follow, structured as the header

specifies. The data section of the HDU may contain a digital image,

but, except for the first, *it doesn't have to*.  Other possible

formats include tables and multidimensional matrices that are not

images. The first HDU must contain a multidimensional matrix or no

data at all; the data in subsequent HDUs, called extensions, may be of

any type, consistent with certain rules.  The "Image" in the name FITS

comes from the original use of the format to transport digital images,

but it's not just for images any more. 



FITS supports 5 data types in primary or IMAGE data arrays: 8-bit

unsigned binary integers, 16-bit twos-complement signed binary

integers, 32-bit twos-complement signed binary integers, 32-bit

IEEE-754 standard floating point numbers, and 64-bit IEEE-754 floating

point numbers.  For signed integers, the byte that includes the sign

bit is first and the byte that has the 1-bit as its least significant

bit is last. 



FITS does not support the 16-bit unsigned integer data type generated

by many analog/digital converters.   Conforming FITS files can be

produced from such data by subtracting 32768 (decimal) from the

converter output before writing to the file, while setting the BZERO

keyword in the FITS header equal to 32768 and the BSCALE keyword equal

to 1.  A FITS reader will then add 32768 to the value in the file,

restoring the original value, before interpreting it.  Whether a

16-bit unsigned data type should be added, and if so, how, is

controversial and under discussion, especially in sci.astro.fits. 



 1.2 How FITS Evolves



The International Astronomical Union (IAU) FITS Working Group (IAUFWG)

was given authority over FITS matters by the 1988 IAU General

Assembly. This Group is associated with the Working Group on

Astronomical Data. The current chair is D. Wells (NRAO) and the

vice-chair is E. Raimond (NFRA). When the developer of a data

structure finds that it does not fit well into an existing standard

FITS format, a new design may be developed.  No change can be made

that would cause existing FITS files to be out of conformance -- the

"once FITS, always FITS" rule. A unique name for any new extension

type must be registered with the IAU FITS Working Group, optionally

through the FITS Support Office. After astronomical community

discussion, most of which will be electronic, a formal proposal is

distributed. This proposal is discussed by the community and may be

further modified. Tests are run using the new format to confirm that

it can be practically used for data transport. If the astronomical

community reaches a consensus that the proposal should be adopted as

standard FITS, and if successful data transfer using the proposed

extension can be demonstrated, it is submitted for ratification to the

regional committees--the European FITS Committee, the Japanese FITS

Committee, and the American Astronomical Society Working Group on

Astronomical Software (WGAS) FITS Committee. Following approval by the

regional committees, it is submitted to the IAU FITS Working Group.

Approval by the Working Group establishes it as a standard extension. 



 1.3 What FITS Is Not 



FITS is not principally a graphics format designed for the transfer of

pictures; it does not incorporate "FITS viewers," packages for

decoding the data into an image.  Users must develop or obtain

separate software to read and display the data from the FITS file.

There is no standard package for all applications; section 3.5

discusses some possibilities. 



2 FITS Documents



 2.1 Published Papers

	

The fundamental references on FITS are the following five

papers.  The first four have often been referred to collectively as

the "Four FITS Papers". These five papers, along with the Floating

Point Agreement (section 2.5) and the binary tables definition

(section 2.2), are the formal standard for FITS, endorsed by the IAU. 

 

Wells, D. C., Greisen, E. W., and Harten, R. H., "FITS: A Flexible 

Image Transport System," Astronomy and Astrophysics Supplement Series, 

44,  363-370, 1981. 

 

Greisen, E. W. and Harten, R. H., "An Extension of FITS for Small 

Arrays of Data," Astronomy and Astrophysics Supplement Series, 44, 

371-374, 1981. 

(NOTE: The format described in this paper has been used almost 

exclusively to transport radio interferometry and is likely to be 

replaced by other formats in the future.  Writing data other than 

radio interferometry data using this format is not recommended.)   

 

Grosbol, P., Harten, R. H., Greisen, E. W., and Wells, D. C., 

"Generalized Extensions and Blocking Factors for FITS," Astronomy and 

Astrophysics Supplement Series, 73, 359-364, 1988. 

 

Harten, R. H., Grosbol. P., Greisen, E. W., and Wells, D. C., "The 

FITS Tables Extension, Astronomy and Astrophysics Supplement Series, 

73, 365-372, 1988. 



Ponz, J. D., Thompson, R. W., and Munoz, J. R., "The FITS Image 

Extension," Astronomy and Astrophysics Supplement Series, 

105, 53-55, 1994. 



 2.2 Binary Tables



On June 15, 1994, the IAU FITS Working Group announced the acceptance

of BINTABLE, the binary table extension, as a standard extension.  The

description of the extension, to be published in the Astronomy and

Astrophysics Supplement Series, is available at the National Radio

Astronomy Observatory (NRAO) site (see section 4.3). 

                                                                

 2.3 User's Guide



A User's Guide for FITS, commissioned by NASA Headquarters, is

maintained by the FITS Support Office.  This Guide is intended to be a

tutorial for new FITS users. In addition to presenting the rules of

FITS, it provides some of the history and reasoning behind the choice

of the rules, adds recommendations on good practices, and discusses

current developments in FITS.  The current version, 3.1, was issued in

May 1994. 



 2.4 NOST Definition of FITS

 

 2.4.1 Version 1.0



The NASA/Science Office of Standards and Technology (NOST) has

codified FITS as endorsed by the IAU into a formal standard,

eliminating some contradictions and ambiguities in the original FITS

papers.  This Definition of FITS, version 1.0, was developed by a

Technical Panel chaired by R. J. Hanisch (STScI), with review by the

astronomical community.  On June 18, 1993, it was approved as a NOST

Standard by an Accreditation Panel consisting of the NOST Executive

Board and an astronomical community representative; this review was to

confirm that the community had been given a satisfactory opportunity

to review the standard and that the Technical Panel had properly

considered and responded to all comments. 



The NOST standard has been submitted to the IAUFWG for endorsement as

the international FITS standard. Version 1.1 will replace the original

endorsed standard -- the four FITS papers, with the addition of the

Floating Point Agreement. While oversights in non-controversial areas

may be rectified as a result of the review by the IAUFWG, significant

changes are unlikely because members of this committee were active in

the process of reviewing the standard and their comments were given

significant weight in the deliberations of the Technical Panel. 



The IAUFWG has since endorsed the IMAGE and BINTABLE extensions, and

the agreement on physical blocking.  A new Technical Panel has been

formed, primarily to draft a revised NOST Standard incorporating these

additions, but also to rectify any oversights or omissions that may be

brought to its attention by the community. Dr. Hanisch, the chair of

the panel that developed version 1.0 of the Definition of FITS, is

chairing this new panel. 



  2.4.2 Proposed Revision on Units Specification



In response to community comments on the version 1.0 treatment, the

new panel developed and released text covering requirements and

recommendations on units to be used in FITS files. The Technical Panel

has now approved the submission of this text for NOST accreditation as

a revision to the NOST Standard.  The proposed text is available in

flat ASCII text form, with an approximate length of two printed pages.

The NSSDC Coordinated Request and User Support Office (see section 6)

can provide printed copies and electronic copies for those without ftp

access.  Upon approval by the Accreditation Panel, this text will be

incorporated in the NOST Definition of FITS, producing version 1.1. 



 2.5 Floating Point Agreement



Originally, FITS permitted only integers in the data array following

the first, or primary header.  The IAU has since endorsed the Floating

Point Agreement, which specifies the use of IEEE-754 floating point

and describes its use in FITS.  The basic agreement appears verbatim

in the User's Guide, and the substance is incorporated in the NOST

standard. 



 2.6 Blocking Agreement



The IAU FITS Working Group has endorsed a set of rules for physical

blocking of FITS files, designed to address the requirement that many

controllers and devices for high density storage media can access data

only in blocks of fixed length.  These rules prescribe the number of

2880-byte FITS logical records in a physical block and how to proceed

when the block size is not an integral multiple of 2880 bytes. They

have been formulated for fixed-block sequential media, variable block

sequential media, and bitstream devices. They are available in this

directory in the file blocking94.txt. 



 2.7 List of Registered Extensions



The rules for generalized extensions in FITS require a unique name for

every extension type, to permit software readers to identify whether

or not an extension is of a type that the software can handle.  In

order to ensure uniqueness, all extension type names, even for local

extensions used only at one installation, must be registered with the

IAU FITS Working Group. The FITS Support Office maintains the List of

Registered Extensions, in this directory, in the file xtension.lis.

This list includes a brief description of the extension each type name

identifies, the developer or responsible organization, and the status

of the extension (e. g., standard, under discussion, local). Also

described is the procedure for registration of extension type names. 

This list is updated as new extension type names are proposed and

extensions with reserved names progress through the process required

for IAU FITS Working Group approval. Consequently, it should be used

as the primary reference on registered extensions rather than the

appendix in the Definition of FITS or the corresponding section in the

User's Guide. 



 2.8 World Coordinates



A draft text of conventions for World Coordinates is currently under

community review.  It proposes rules for describing the physical

coordinate values attached to each member of a FITS data array, with

detailed discussion of projections from the celestial sphere to the

array plane.  It is available electronically from the NRAO site (4.3).



 2.9 Proposed Conventions



R. Seaman and W. Pence have proposed a scheme for embedding a checksum

within a FITS header.  This checksum could be used to verify that the

data in a file were transported without errors.  A copy is available

from ftp://iraf.noao.edu/misc/checksum/. IAU FITS Working Group Chair

D. Wells has recommended that this proposal be considered by the

regional FITS committees. 



D. Jennings, W. Pence, M. Folk, and B. Schlesinger have proposed a

convention for logically grouping together FITS HDUs that are

physically separated in a given file or are located in different

files.  This convention would facilitate HDU-FITS conversion. Versions

in LaTeX/PostScript are available at

ftp://ssvs.gsfc.nasa.gov/pub/convert/; an html version may be viewed

at http://acadia.gsfc.nasa.gov/convert/group.html. 



3 Software and Sample Data



 3.1 FITS Support Office



All FITS Support Office software is available from this ftp site.



  3.1.1 FITS Product Conformance Tester with Instructions

	

The FITS Product Conformance Tester (FPCT), under development by the

FITS Support Office, is a software package designed to validate FITS

files. The programs are coded in C. The available prototype validates

required keywords in the primary header and, at the user's option,

prints selected values from the primary data array. Even after finding

an error in a required keyword, it will continue to evaluate the file,

looking for additional errors in required keywords.  If the user

specifies, and if major header syntax errors do not prevent retrieval

of the array dimensions, the FPCT will try to read the primary data

array. The separate instructions should be read before running the

software.  In addition to providing directions for use, they also 

discuss the capabilities and limitations of the prototype. 



  3.1.2 Header Lister 



This program prints out all the headers in a FITS file, including the

primary header and all extension headers.  It does not evaluate them

for errors.  It is a useful tool for obtaining a quick summary of the

contents of a FITS file.  It is written in ANSI C; users with Sun and 

other systems that normally use earlier C dialects will need to 

devolve the function prototyping syntax or use an ANSI C compiler.



  3.1.3 Error Test Files



These files consist of several versions of the same FITS file, one in

conformance with the FITS standard and recommended practices, several

with different kinds of header errors, and two that are in technical

conformance but have features that might cause problems for some

readers.  The are useful for testing the ability of FITS reading

software to cope with erroneous or unusual files and to identify

correctly the errors encountered. Users who download the files from

direct anonymous ftp should remember to use binary transfer. 



 3.2 HEASARC



The NASA/Goddard High Energy Astrophysics Science Archive Research

Center (HEASARC) has developed and maintains FITS software and

utilities, including the FITSIO package and the FTOOLS utilities. See

4.2 for information on electronic access to FITSIO and supporting

documentation. 

	

  3.2.1 FITSIO 



The FITSIO package, maintained by W. D. Pence, is a

machine-independent subroutine interface for reading or writing data

files in FITS format. FITSIO is written in portable Fortran-77 and

runs on most commonly used computers. In addition to the Fortran

subroutine interface, a set of C macros, one for each FITSIO

subroutine is provided to make it easier to call FITSIO from C

programs. FITSIO supports all the standard FITS extensions and

contains world coordinates subroutines for conversion between pixel

and celestial coordinates. In addition, software support for the

checksum proposal is available. 

 

  3.2.2 FTOOLS



J. K. Blackburn and W. D. Pence document the FTOOLS collection of over

100 utility programs to create, examine, or modify FITS data files.

These programs are useful for examining the contents of FITS files and

modifying them for input to more involved analysis tasks; they cannot

generally be used for detailed data analysis or model fitting.  New

versions are released about every 3 months. Users have the option of

installing the entire FTOOLS package, which includes many routines

specific to high energy astrophysics, or a core set that contains only

the routines that perform general operations on FITS files. FTOOLS can

be built as a package within IRAF or as a set of stand-alone

executable tasks. FTOOLS is supported on the following platforms: 

                                        

Unix: ALPHA/OSF, DEC/ULTRIX, SUN/SunOS, SUN/Solaris, MODCOMP/REALIX

VMS:  ALPHA/VMS, VAX/VMS.



Questions or comments should be sent to ftoolshelp@athena.gsfc.nasa.gov



  3.2.3 VERIFITS



W. D. Pence (GSFC/HEASARC) has announced the VERIFITS program to

verify the conformance of any FITS format data file on magnetic disk

to the standard, checking keywords and data.  At user option it will

list the total number of pixels, the number of null pixels and the

maximum and minimum data values.  If an error is found while

evaluating the header, validation ceases, the error is reported and

the first 72 keywords of the header are listed. The VERIFITS program

is a stand-alone version of the fverify task that is included in the

IRAF or Host FTOOLS package. Both VERIFITS and fverify perform the

same verification checks, but fverify has a nicer user interface, as

provided by the IRAF or Host environments. Several different binary

executable versions of VERIFITS are available, for running on Sun

workstations, DECstations, DEC Alphas running OSF/1 or VAX/VMS

machines. The VERIFITS source code is also provided and may be easily

linked with the FITSIO library to run on the other types of machine on

which FITSIO is supported.  While VERIFITS has been extensively

tested, under some unusual circumstances not covered by the tests it

may still fail to detect a FITS format error, or it may issue an error

message that does not accurately describe the problem. 



VERIFITS has broader applicability than the FITS Product Conformance

Tester (FPCT), being able to handle all standard extensions, while the

currently available FPCT can handle only primary HDUs. The FPCT

however is more forgiving and more thorough; VERIFITS will usually

reject a file after finding one error, while the FPCT will attempt to

retrieve the information needed to read the data if doing so is

possible even with errors in the file, and will continue to check the

header even after an error has been found. 



The VERIFITS program is available at

ftp://heasarc.gsfc.nasa.gov/software/fitsio/verifits/. 



 3.3 ADC FITS Table Browser 



The Astronomical Data Center has developed a FITS Table Browser, which

has been tailored specifically for use with the ADC CD-ROMs but may be

used with other FITS ASCII Tables. It reads standard FITS ASCII tables

and allows the user to browse through them interactively and

selectively display any field or record in a table. File extraction

facilities allow the writing of all or part of the input table to disk

in FITS or text file format. 



Copies of the program for MS-DOS and Unix are available at

ftp://nssdc.gsfc.nasa.gov/pub/ADC/software/ftb/. See the file

README.FTB for instructions on downloading, installation, and use. 



 3.4 FITS I/O software in IDL



W. Landsman (Hughes STX; landsman@stars.gsfc.nasa.gov) has announced

that FITS I/O software written in IDL is available as part of the IDL

Astronomy User's Library, a central repository for general purpose

astronomy procedures written in IDL, including procedures to convert

between spherical coordinates and plan map coordinates.  The library

is not meant to be an integrated package, but rather is a collection

of procedures from which users can select. Submitted procedures are

given a cursory testing but are basically stored in the library as

submitted.  The IDL Astronomy User's Library is supported under the

NASA Astrophysics Software Aids program and is available at

ftp://idlastro.gsfc.nasa.gov.  Get the README file for details. 





 3.5 Display of FITS Image Files 

	Disclaimer: The mention of particular software packages is not

intended as an endorsement of those packages to the exclusion of

others.  Users should obtain proper licensing for any proprietary

package or format mentioned. Information about publicly available

nonproprietary packages is welcome and will be added to this posting

if the package appears relevant and useful.  Such information should

include how to obtain the package and whom to contact with questions.

It should also describe any limits on the FITS files that the package

can handle (e. g., NAXIS must be 2; data array members must be

integers). 

  

  3.5.1 Major Astronomical Image Analysis Packages



The three major astronomical image analysis packages -- the

Astronomical Image Processing System (AIPS), the European Southern

Observatory Munich Image and Data Analysis System (ESO-MIDAS), and the

Image Reduction and Analysis Facility (IRAF) -- provide facilities for

displaying images stored in FITS files.  These packages are large and

probably best installed on major systems. AIPS was developed by the

National Radio Astronomy Observatory (NRAO), and IRAF by the National

Optical Astronomy Observatories (NOAO). 

                                                

  3.5.2 pbm+



The Extended Portable Bitmap Toolkit (pbm+) can be used to convert

many FITS files to image format. However, support is not guaranteed

for all FITS files where the data are in the form of an image.  In

particular, there may be problems when the data array members are in

IEEE floating point format (BITPIX<0) or the array has more than two

dimensions (NAXIS>2). 



  3.5.3 IMDISP (IBM/PC)



A. Warnock and R. Baalke have announced release of version 7.9 of

IMDISP, an interactive image processing program that runs on an IBM PC

computer and supports FITS input. IMDISP 7.9 is available at

ftp://explorer.arc.nasa.gov/pub/SPACE/SOFTWARE/ (128.102.32.10) in a

file called imdisp79.zip and from

ftp://nssdc.gsfc.nasa.gov/pub/ADC/software/imdisp/ . 



  3.5.4 SAOimage





SAOimage is an X11 display tool which can be used stand-alone

or in conjunction with IRAF to display FITS or IRAF images. It was

developed at Smithsonian Astrophysical Observatory.  SAOimage source

code as well as compiled executables for SUN, HP, DEC, and VMS

workstations are available at ftp://sao-ftp.harvard.edu/pub/saoimage/

(128.103.42.3).  Questions about the use of SAOimage may be sent to 



        hotseat@cfa.harvard.edu

or

        iraf@noao.edu



New bug fixes to SAOimage currently are being provided by NOAO in

order to ensure that SAOimage will continue to work with IRAF.  A new

version of SAOimage, called "SAOimage: The Next Generation (SAOtng)"

is being developed as a joint project between SAO and NOAO.  An alpha

release is planned for the spring of 1995. 



  3.5.5 Applications with XV



The XV package, as of version 3.10a, now includes FITS support.  It

can handle more than 2 axes and IEEE single and double precision

regular floating point values in the primary array.  It can not handle

IMAGE extensions or IEEE special values (NaN, Infinity, denormalized).

The package is available from ftp://ftp.cis.upenn.edu/pub/xv/ as

Z-compressed and GNU compressed .tar files.  That site also lists

electronic mail addresses for general XV questions, technical

questions, and questions about licensing. 



  3.5.6 FITS and the Macintosh



<H4><A NAME= "FITSMac">FITS and the Macintosh</a></H4>



	T. Lemke (100102.104@compuserve.com), at Peine in Germany

has added FITS support to GraphicConverter for the Macintosh and

provided the following information.  GraphicConverter 1.7.7 or later

can import FITS array files with all five permitted data types (8, 16,

32 bit integer and 32, 64 bit real). Every FITS file will be converted

to 8 bit gray scale on opening because this is the maximum number of

grays on a Macintosh. GraphicConverter can convert a FITS files to the

PICT, TIFF, GIF, PCX, IFF, PPM, and other graphic file formats.

GraphicConverter is available via the ftp info-mac archives at

ftp://ftp.amug.org/pub/info-mac/gst/grf/ in the folder

graphic-converter-212*.  This site is often busy.  If Web access

through the URL does not succeed, use an ftp client to access

ftp.amug.org for information on mirror sites.<P> 



D. Norton of Otter Solution has written a Photoshop plug-in called

"PhotoFITS" which reads 8-, 16-, or 32-bit integer and 32- or 64- bit

floating point FITS images and converts them to 8-bit or RGB images. 

It allows conversion of three-image FITS files to RGB.  It allows

multiple image files to be read in as a mosaic.  It can be found at 

	ftp://zippy.nimh.nih.gov/pub/nih-image/plug-ins/



Questions and problem reports should be sent to ottersol@aol.com.



  3.5.7 FITSview (Windows)



W. Cotton at NRAO has announced an updated beta release, version

0.4.0, of FITSview, a FITS image viewer for Windows. Celestial

positions are determined using world coordinate projections. All

defined FITS data types are recognized, as are blanked pixels.  Two

and three dimensional simple FITS images can be viewed. FITSview runs

on Windows 3.1 or later and uses any multicolor (or multiple gray

level) display. Extensive on-line documentation is included. It is

available by ftp from the NRAO site: 

 ftp://fits.cv.nrao.edu/fits/os-support/ms-windows/fitsview/fitsv040.txt

 ftp://fits.cv.nrao.edu/fits/os-support/ms-windows/fitsview/fitsv040.zip

Installation is described in fitsv040.txt.



 3.6 World Coordinates



Two ANSI C functions, worldpos() and xypix(), convert (RA, dec) <-->

pixel location for 8 common types of projective geometries where

"(RA,Dec)" are more generically (long,lat). These functions are based

on the World Coordinates implementation of Classic AIPS. The software

is in src/wcs/worldpos.tar.gz at the NRAO site (section 4.3) and

supporting documentation can be found in documents/wcs/. 



M. Calabretta (ATNF) has announced the general release of WCSLIB 1.0 -

a suite of routines which implements the spherical projections

proposed for the "World Coordinate System" (WCS) convention in FITS

discussed in 2.6.  The WCSLIB distribution kit contains independent C

and FORTRAN implementations of the library.  It is available via

anonymous ftp from 

 

   ftp.atnf.csiro.au:/pub/software/wcslib/wcslib-1.0.tar.gz

 

and also

 

   fits.cv.nrao.edu:/fits/src/wcs/wcslib-1.0.tar.gz

 

4 On-line Information Sources



 4.1 FITS Support Office 	

	

The FITS Support Office maintains this directory of FITS information

at ftp://nssdc.gsfc.nasa.gov/pub/fits. The aareadme.doc file describes

the contents of this directory. The software and errtest

subdirectories contain separate aaareadme.doc files describing their

content. 



 4.2 HEASARC



The HEASARC FITS software, utilities, and accompanying

documentation are available as follows:



ftp://legacy.gsfc.nasa.gov/software/fitsio 

	contains the FITSIO package, and supporting documentation. 

ftp://legacy.gsfc.nasa.gov/software/fitsio/verifits 

	contains the VERIFITS validator and supporting documentation. 

ftp://legacy.gsfc.nasa.gov/software/ftools/release 

	contains the FTOOLS collection, and supporting documentation. 

The FTOOLS software is being distributed as compressed tar files. 



All three directories contain informational README files.



HEASARC also provides information on the activities of the

OGIP/HEASARC FITS Working Group (OFWG), the internal legislative body

on FITS-related matters within the Office of Guest Investigator

Programs (OGIP) at NASA/GSFC. OFWG has developed a number of FITS

conventions that are more specific than the requirements of the FITS

standards. Proposed OGIP conventions are publicized to the FITS

community as a whole, with the goal of collaborative development of a

set of conventions that will be accepted throughout the community as

well as within OGIP/HEASARC. 



 4.3 NRAO



A library of FITS material can be found at

ftp://fits.cv.nrao.edu/fits, located at NRAO.  This machine supports a

WAIS server named nrao-fits which has an index of all of the

FITS-related text files in the archive; the file nrao-fits.src is

available at think.com and at

ftp://fits.cv.nrao.edu/fits/wais-sources/nrao-fits.src.  There is a

World Wide Web server for the FITS Archive as well, at the URL

http://fits.cv.nrao.edu.    



The documents subdirectory of the fits directory contains a number of

subdirectories.  The BINTABLE draft for Astronomy and Astrophysics is,

in various formats, in files bintable_aa.*. A proposals subdirectory

is reserved for detailed proposals currently being considered by the

FITS committees.  A drafts subdirectory contains drafts of designs not

yet submitted.  The wcs subdirectory contains a draft of the current

proposal for world coordinate system conventions now under community

review and earlier documents and presentations on world coordinates.

Other subdirectories include sample FITS files -- both actual data

files and files specially constructed to test the ability of software

to read all kinds of FITS structures, some code for particular

environments, pointers to other code, and an archive of Usenet

postings related to FITS. 



4.4 HEAFITS Exploder



An electronic mail listserver called HEAFITS has been set up for

discussion of High Energy Astrophysics-specific FITS issues that

would not necessarily be of interest to the majority of subscribers to

the sci.astro.fits newsgroup and fitsbits mailing list. To *subscribe*

to the HEAFITS group, send the following one-line e-mail message to

listserv@legacy.gsfc.nasa.gov: 

		subscribe heafits Your Name 

where 'Your Name' is your actual First and Last names. Messages to the

actual mailing list should be sent to heafits@legacy.gsfc.nasa.gov.

There is an archive of messages at

http://heasarc.gsfc.nasa.gov/listserv/heafits/maillist.html . 



5. Some contributors (non-exhaustive list)



A. Bernstein (JPL)

D. Beauchamp (U. Laval)

W. Cotton (NRAO)

C. S. Grant (CfA)

T. Lemke (U. of Brunswick)

W. Pence (GSFC/HEASARC)

D. Wells (NRAO)

and the participants in sci.astro.fits and the fitsbits mailing list



6. FITS Support Services from GSFC



The NSSDC Coordinated Request and User Support Office (CRUSO) can

provide printed copies of the User's Guide and the NOST Standard.

CRUSO can be reached as follows: 



(Postal) Coordinated Request and User Support Office

         Code 633

	 National Space Science Data Center

	 NASA Goddard Space Flight Center

	 Greenbelt MD 20771 USA



(Electronic mail) request@nssdca.gsfc.nasa.gov



(Telephone)  +1-301-286-6695 8:00 A. M. - 4:30 P.M. U. S. Eastern Time

(-0500 from the last Sunday in October through the first Saturday in

April; -0400 the remainder of the year) 

	When no one is available, messages can be left on voice mail. 



(FAX) +1-301-286-1635

 

Because of restrictions set by ESO, the copyright holder, copies of

the four FITS papers may be sent only to non-profit organizations, .

The IEEE floating point standard is copyrighted by IEEE, and must be

purchased from them.  Ordering and contact information is on-line at

http://stdsbbs.ieee.org:70/0/pub/htmlfiles/stcord/html . 



Use the FITS Support Office electronic mail address below for

questions about this FITS information. Other staff members monitor the

FITS electronic mail address when I am away from the office, providing

a greater certainty of rapid response.  Please provide your name,

affiliation, and location. 



					Barry M. Schlesinger

					Coordinator,				

					FITS Support Office

		

+1-301-441-4205				fits@nssdca.gsfc.nasa.gov

					NCF::FITS

 



NASA Contacts:



ADF - David Leisawitz(leisawitz@stars.gsfc.nasa.gov)

NOST - Donald M. Sawyer (sawyer@nssdca.gsfc.nasa.gov)





