From fitsbits-request  Fri Sep  2 12:01:42 1994
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	["825" "" " 2" "September" "1994" "15:28:07" "GMT" "psada" "psada at acca.nmsu.edu" "<347ga7$p5q at dns1.NMSU.Edu>" "20" "Help with IMDISP." "^From:" nil nil "9" "1994090215:28:07" "Help with IMDISP." (number " " mark "     psada             Sep  2   20/825   " thread-indent "\"Help with IMDISP.\"\n") nil]
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From: psada at acca.nmsu.edu (psada)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Help with IMDISP.
Date: 2 Sep 1994 15:28:07 GMT
	Hi. I am a new to FITS. I was attempting to use Version 7.9
of IMDISP, which is a FITS viewer for the PC, and had some trouble
getting it to work. I downloaded and unzipped it with no apprent
problems. However, when I run it the program refuses to recognize
even its own sample files as having the proper format (ie. it does
not load its own demo files properly) asking me for info about the
file that it is obviously reading correctly from the header (I used
the LABel command).
	I have tried this on three different PCs with the same
result. Even downloaded it again. Am I missing something? Is there
a flag or environment variable that I have to set? The manual does
not cover anything about errors in its own sample files.
	Any help will be appreciated. Thank you.
						Pedro Valdes Sada
						psada at acca.nmsu.edu
From fitsbits-request  Mon Sep  5 09:01:32 1994
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	["529" "" " 3" "September" "1994" "01:13:04" "" "Alan Sawyer" "Alan.Sawyer at p1305.f158.n633.z3.fidonet.org" "<370_9409051914 at unique.pronet.com>" "11" "Postscript??" "^From:" nil nil "9" "1994090301:13:04" "Postscript??" (number " " mark "     Alan Sawyer       Sep  3   11/529   " thread-indent "\"Postscript??\"\n") nil]
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From: Alan.Sawyer at p1305.f158.n633.z3.fidonet.org (Alan Sawyer)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Postscript??
Date: 03 Sep 94 01:13:04 +
Whilst escaping from government goons,xmosa at vega.pd.astro.it yelled out .....
 xm> In article <33kg9p$lo at hugin.aau.dk>, norup at indigo (Anton Norup
 xm> Soerensen) writes: |>
 |>I would like to know of programs available for converting FITS images
 |>to GIF format. I will also be interested to hear of programs to
 |>combine three, e.g. B,V,R images to one 'true-colour' GIF image.
How do I view/print these post script things too??? On an IBM,
... "I'm a citizen of Legoland travellin Incommunicado" - Fish
---
 * TLX v3.10 *
From fitsbits-request  Tue Sep  6 23:20:05 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1408" "" " 7" "September" "1994" "01:12:33" "GMT" "Carl J Lydick" "carl at SOL1.GPS.CALTECH.EDU" "<34j421$gm8 at gap.cco.caltech.edu>" "22" "Re: Postscript??" "^From:" nil nil "9" "1994090701:12:33" "Postscript??" (number " " mark "     Carl J Lydick     Sep  7   22/1408  " thread-indent "\"Re: Postscript??\"\n") "<370_9409051914 at unique.pronet.com>"]
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References: <370_9409051914 at unique.pronet.com>
Reply-To: carl at SOL1.GPS.CALTECH.EDU
From: carl at SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: Postscript??
Date: 7 Sep 1994 01:12:33 GMT
In article <370_9409051914 at unique.pronet.com>, Alan.Sawyer at p1305.f158.n633.z3.fidonet.org (Alan Sawyer) writes:
=Whilst escaping from government goons,xmosa at vega.pd.astro.it yelled out .....
= xm> In article <33kg9p$lo at hugin.aau.dk>, norup at indigo (Anton Norup
= xm> Soerensen) writes: |>
= |>I would like to know of programs available for converting FITS images
= |>to GIF format. I will also be interested to hear of programs to
= |>combine three, e.g. B,V,R images to one 'true-colour' GIF image.
=How do I view/print these post script things too??? On an IBM,
=.... "I'm a citizen of Legoland travellin Incommunicado" - Fish
You might try checking whether there's an implementation of Ghostscript for the
system you use.  If I recall correctly, Ghostscript is part of the GNU project,
and should be available via anonymous FTP from PREP.AI.MIT.EDU [18.71.0.38].
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL at SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
From fitsbits-request  Fri Sep  9 10:19:43 1994
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	["1108" "Fri" " 9" "September" "1994" "16:19:46" "+0200" "Preben Grosbol" "pgrosbol at eso.org" "<9409091419.AA24827 at ns2.hq.eso.org>" "27" "IAU General Assembly in Den Haag" "^From:" nil nil "9" "1994090914:19:46" "IAU General Assembly in Den Haag" (number " " mark "     Preben Grosbol    Sep  9   27/1108  " thread-indent "\"IAU General Assembly in Den Haag\"\n") nil]
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From: Preben Grosbol <pgrosbol at eso.org>
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: iaufwg at fits.CV.NRAO.EDU
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Subject: IAU General Assembly in Den Haag
Date: Fri, 09 Sep 1994 16:19:46 +0200
Dear Colleagues,
 There were several meeting related to the IAU FITS Working Group
during the IAU General Assembly in Den Haag Aug. 17-24, 1994. The
two most important points were:
 1) In the business meeting of Commission 5 on 18.8, the new
    structure was discussed. It will associate the FITS Working
    Group to the Working Group on Astronomical Data. It was
    emphasized in the discussion that FITS WG has the authority
    to maintain the FITS standard and to review, approve and
    maintain future extensions to FITS (ref. resolution B2
    of the 20th General Assembly). This infers that the FITS
    Group will have a very long life span to ensure the long
    term stability of FITS.
 2) Don Wells was elected new Chairman for the FITS Working Group
    with Ernst Raimond as Vice-chairman.
I would like to take this opportunity to thank you all for your
support and work in the FITS Working Group during the last years.  It
is a pleasure to wish both Don and Ernst all the best with respect to
the many important issues to be discussed in the coming years.
Best regards
Preben Grosbol
From fitsbits-request  Sat Sep 10 18:53:23 1994
Status: RO
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	["2823" "Sat" "10" "September" "1994" "03:13:06" "GMT" "Don Wells" "dwells at nrao.edu" "<DWELLS.94Sep9231306 at fits.cv.nrao.edu>" "63" "Re: IAU General Assembly in Den Haag" "^From:" nil nil "9" "1994091003:13:06" "IAU General Assembly in Den Haag" (number " " mark "     Don Wells         Sep 10   63/2823  " thread-indent "\"Re: IAU General Assembly in Den Haag\"\n") "<9409091419.AA24827 at ns2.hq.eso.org>"]
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From: dwells at nrao.edu (Don Wells)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: IAU General Assembly in Den Haag
Date: Sat, 10 Sep 1994 03:13:06 GMT
Dear Colleagues,
I thank Preben Grosbol for his good wishes for me and for Ernst
Raimond as we begin our term as Chairman and Vice-Chairman of the IAU
FITS Working Group. I am sure that all friends of FITS will join me in
thanking Preben for his excellent leadership of the FITS community
during the past twelve years.  Preben's final term as Chair of the
IAU-FWG ended in an especially memorable fashion, with the final
acceptance of BINTABLE, IMAGE and Blocking as FITS standards.
During the FITS Working Group session in Den Haag on August 23rd,
Preben asked me to discuss plans for the next triennium. My vugraph
was titled "IAU-FWG project list for 1994-97", with these items:
1) Review/modify the relationship between FWG and IAU-EC+Comm5
As Preben noted in his message, we made real progress on this
critically important action item during the sessions at Den Haag, but
several questions remain to be settled during the coming triennium.
2) Approve the NOST FITS document (need units agreement)
The NOST FITS standard document has been in preparation for nearly
five years with the specific goal that it should be accepted by the
IAU FITS WG as the definitive standard for the FITS data format. Soon
this document will be submitted to the FITS community for review.
3) Make progress toward a WCS agreement
R&D efforts on "world coordinate systems" [WCS] for FITS began more
than ten years ago, and interoperable implementations were deployed
for radio interferometers and for the Einstein and IRAS spacecraft
during the 80s. The latest releases of IRAF support WCS, and are
interoperable with the prior implementations. The time appears to be
ripe for the WCS agreement. The latest draft of the WCS proposal,
ftp://fits.cv.nrao.edu/fits/documents/wcs/wcs.all.ps.Z, will be
discussed at the FITS Birds-Of-a-Feather session at the ADASS'94
meeting in Baltimore two weeks from now.
4) Make progress toward a compression agreement
I intend to encourage a renewed R&D effort on compression for FITS.
5) Register FITS with the Internet (IANA) as a MIME data type.
I intend to ask the IAU-FWG for permission to apply to the Internet
Assigned-Numbers Authority for a MIME [Multimedia Internet Mail
Extensions] code for FITS, so that FITS file objects can be
encapsulated in Email messages, and will be recognized by
non-astronomy application code.
I will be happy to receive comments about these action items, or about
other potential projects which the FITS community could undertake.
Best regards,
Don Wells
Chairman, IAU FITS Working Group
--
  Donald C. Wells         Associate Scientist         dwells at nrao.edu
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA
From fitsbits-request  Thu Sep 15 09:50:52 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1548" "" "15" "September" "1994" "07:01:56" "GMT" "Gregg W. Riedel" "gregg at hcirisc.cs.binghamton.edu" "<GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>" "34" "FITS data question" "^From:" nil nil "9" "1994091507:01:56" "FITS data question" (number " " mark "     Gregg W. Riedel   Sep 15   34/1548  " thread-indent "\"FITS data question\"\n") nil]
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From: gregg at hcirisc.cs.binghamton.edu (Gregg W. Riedel)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: FITS data question
Date: 15 Sep 1994 07:01:56 GMT
Hi!
   I'm a graduate student in computer science, with zero knowledge of
astronomy.  I am implementing a FITS reader for an image processing
package.
   I have fetched a test image from the Hubble telescope of Saturn
(w0ck0101t_c0h.fit), and I noticed that the FITS data is broken into
3 axes (800 x 800 x 4); these are apparently separated image planes.
The questions:  what kind of separation is used (RGB?, CMYK, other?),
and where in the file might I find this information?  Is there a
standard for color images?  The literature seems to point toward all
"images" as being greyscale.
   Please forgive my misuse of FITS terminology; I understand the extreme
flexibility of this format, but am solely interested in getting some
pictures :)
Thanks!
Gregg
---------------------------------------  //  --------------------------------
Gregg William Riedel                    //              Binghamton U. - MS-CS
consp24 at bingsuns.pod.binghamton.edu \\ // Amiga        Sr. Systems Consultant
gregg at HCIRisc.cs.binghamton.edu      \X/ 4000/040        ImageFX 2.0 Dev Team
-----------------------------------------------------------------------------
--
---------------------------------------  //  --------------------------------
Gregg William Riedel                    //              Binghamton U. - MS-CS
consp24 at bingsuns.pod.binghamton.edu \\ // Amiga        Sr. Systems Consultant
gregg at HCIRisc.cs.binghamton.edu      \X/ 4000/040        ImageFX 2.0 Dev Team
-----------------------------------------------------------------------------
From fitsbits-request  Thu Sep 15 18:52:14 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1475" "" "15" "September" "1994" "22:00:27" "GMT" "Carl J Lydick" "carl at SOL1.GPS.CALTECH.EDU" "<35ag5r$9br at gap.cco.caltech.edu>" "30" "Re: FITS data question" "^From:" nil nil "9" "1994091522:00:27" "FITS data question" (number " " mark "     Carl J Lydick     Sep 15   30/1475  " thread-indent "\"Re: FITS data question\"\n") "<GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>"]
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References: <GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>
Reply-To: carl at SOL1.GPS.CALTECH.EDU
From: carl at SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: FITS data question
Date: 15 Sep 1994 22:00:27 GMT
In article <GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>, gregg at hcirisc.cs.binghamton.edu (Gregg W. Riedel) writes:
=
=Hi!
=   I'm a graduate student in computer science, with zero knowledge of
=astronomy.  I am implementing a FITS reader for an image processing
=package.
=
=   I have fetched a test image from the Hubble telescope of Saturn
=(w0ck0101t_c0h.fit), and I noticed that the FITS data is broken into
=3 axes (800 x 800 x 4); these are apparently separated image planes.
Er, no.  They're images from each of four separate CCDs, not four separate
colors.  All images from the HST are monochromatic, in that they're images
taken through a specific filter.
=The questions:  what kind of separation is used (RGB?, CMYK, other?),
=and where in the file might I find this information?  Is there a
=standard for color images?  The literature seems to point toward all
="images" as being greyscale.
The images ARE greyscale.
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL at SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
From fitsbits-request  Thu Sep 15 22:46:55 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["3201" "Fri" "16" "September" "1994" "02:34:04" "GMT" "Don Wells" "dwells at nrao.edu" "<DWELLS.94Sep15223405 at fits.cv.nrao.edu>" "79" "FITS-support for Mathematica" "^From:" nil nil "9" "1994091602:34:04" "FITS-support for Mathematica" (number " " mark "     Don Wells         Sep 16   79/3201  " thread-indent "\"FITS-support for Mathematica\"\n") nil]
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From: dwells at nrao.edu (Don Wells)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: FITS-support for Mathematica
Date: Fri, 16 Sep 1994 02:34:04 GMT
I thank Fred Schwab <fschwab at nrao.edu> for alerting me to the
existence of this thread in newsgroup sci.math.symbolic. -Don Wells
    -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Newsgroups: sci.math.symbolic
From: abraham at haida (Bob Abraham)
Subject: MMA and FITS format images
Nntp-Posting-Host: haida.dao.nrc.ca
Organization: University of Victoria
Date: Wed, 14 Sep 94 00:49:18 GMT
Hi,
Has anybody written a routine to let Mathematica read images in FITS
format? If so, I'd be very grateful if you would get get in touch with
me.
Cheers,
Bob
PS. in case anybody is curious: FITS (Flexible Image Transport Format)
images are mixed text/binary format files that are becoming a de-facto
standard for use in astronomy.
--
-----------------------------------------------------------------------------
Dr. R. G. Abraham                    |  Internet: abraham at dao.nrc.ca
Dominion Astrophysical Observatory   |  Bitnet:   abraham at nrcdao.nrc.ca
Herzberg Institute of Astrophysics   |  phone:  (604) 363-0028
National Research Council of Canada  |  fax:    (604) 363-0045
5071 W. Saanich Rd.                  |  telex:  049-7295
Victoria, B.C., V8X 4M6              |
CANADA                               |
-----------------------------------------------------------------------------
    -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
From: elsner at avalon.msfc.nasa.gov (Ron Elsner)
Newsgroups: sci.math.symbolic
Subject: Reading FITS files in Mma
Date: 14 Sep 1994 18:29:54 GMT
Organization: NASA/MSFC
I do not have a package to read all FITS files with one cammand, but I can
read them treating each case separately.
To read even modest sized binary files in Mathematica you MUST obtain the
FastBinaryFiles MathLink Package from MathSource.  You can do this via
anonymous ftp to ftp.wri.com.  You will have peruse their index to find
it, or ask Wolfram Research Inc.  After compiling the source code you can
read FITS files as follows (simple example):
Link to the package:
 SetDirectory[ "~/AXAF93Math/MathSource" ] ;
 link = Install[ "binary" ]
Open the input file:
 infile = OpenReadBinary[ "image.fit" ]
Read the 36 (or whatever) record, 80 columns per record, ascii header:
 TableForm[ hdr =
 Table[ FromCharacterCode[ ReadListBinary[ infile, Byte, 80 ] ], {36} ] ]
Read the binary image using information from the header:
     image = Partition[ ReadListBinary[ infile, Int16 ], 512 ] ;
In the above case, the header tells us that this is a 512 (1st axis) by
480 (2nd axis) image with 16 bits per data pixel.  The array image will
have dimensions 480 by 512, which you can Transpose if you like.
Hope this helps.
--------------------------------------------------------------------------
Ron Elsner/ES84                                 205-544-7741
NASA Marshall Space Flight Center               205-544-7754 (Fax)
Huntsville, AL 35812                            elsner at ssl.msfc.nasa.gov
--
  Donald C. Wells         Associate Scientist         dwells at nrao.edu
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA
From fitsbits-request  Fri Sep 16 01:17:08 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1066" "" "15" "September" "1994" "16:52:05" "GMT" "Bob Hanisch, ST ScI" "hanisch at stsci.edu" "<359u3l$t3p at marvel.stsci.edu>" "18" "Re: FITS data question" "^From:" nil nil "9" "1994091516:52:05" "FITS data question" (number " " mark "     Bob Hanisch, ST S Sep 15   18/1066  " thread-indent "\"Re: FITS data question\"\n") "<GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>"]
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Organization: Space Telescope Science Institute, Baltimore MD
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References: <GREGG.94Sep15030157 at hcirisc.cs.binghamton.edu>
Reply-To: hanisch at stsci.edu
From: hanisch at stsci.edu (Bob Hanisch, ST ScI)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: FITS data question
Date: 15 Sep 1994 16:52:05 GMT
Images from HST's Wide Field/Planetary Camera consist of four separate CCD
frames -- these are the four images you are seeing stacked in the FITS file.
They do not form a color composite or anything.  The four frames are stored
this way (actually, only one of several options available to HST users)
purely as a matter of convenience.  Each image has coordinate information
in the header that describes the orientation and position of each frame.
They can be pasted together brute-force to make a mosaic, but to do this
properly requires eliminating region along the edges of each chip that is
unilluminated, and then geometrically correcting three of the four frames
to account for the slight misalignment of the detectors.
_______________________________________________________________________________
Robert J. Hanisch                       Tel. (410)338-4910   Fax. (410)338-5090
Space Telescope Science Institute       NSI: hanisch at stsci.edu [130.167.1.2]
3700 San Martin Drive                   DECNet: STSCIC::HANISCH [6549::]
Baltimore, MD  21218  USA
From dwells  Mon Sep 19 10:23:57 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["3630" "Mon" "19" "September" "1994" "10:23:55" "EDT" "Francois Ochsenbein" "francois at SIMBAD.u-strasbg.fr" nil "69" "FITS tables of astronomical catalogues and Units" "^From:" nil nil "9" nil nil (number " " mark "     Francois Ochsenbe Sep 19   69/3630  " thread-indent "\"FITS tables of astronomical catalogues and Units\"\n") nil]
	nil)
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From: francois at SIMBAD.u-strasbg.fr (Francois Ochsenbein)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits
Subject: FITS tables of astronomical catalogues and Units
Date: Mon, 19 Sep 94 10:23:55 EDT
------- start of forwarded message (RFC 934) -------
Message-Id: <9409161659.AA26838 at SIMBAD.u-strasbg.fr>
From: francois at SIMBAD.u-strasbg.fr (Francois Ochsenbein)
To: fitsbits-request at fits.CV.NRAO.EDU
Subject: FITS tables of astronomical catalogues and Units
Date: Fri, 16 Sep 94 18:59:30 +0200
At CDS (Centre de Donnees astronomiques de Strasbourg) we have a large
quantity (> 900) of astronomical catalogues, most of these being made
of one or more tables.
Descriptions of all these tables are being homogeneized according to
standards (document referenced below) also adopted by the ADC . One of
the important features of this standard is the facility of converting
any of these documented tables into FITS (ascii table extension), and
presently over 500 catalogues have such descriptions.
One of the key issues in the interpretaion of tabular data is the
understanding of the units in which the data are expressed.
The rules adopted in this standard for specifying the units are more
rigid than the OGIP definitions, and since hundreds of tables using
these conventions already exist and are in use, we feel it could be
worthwhile to let the FITS community aware of these conventions for discussion.
The complete definitions concerning units are detailed in the document;
they can be resumed by the 4 rules:
- - the symbol of any unit is a single word (no embedded space)
- - a numeric factor can only precede the symbols, e.g.  0.01arcsec/yr
						   not arcsec/(100yr)
- - operators are only the dot (.) for the multiplication,
  the slash (/) for the division, and integer powers (+ or -).
  with classical precedence rules.
  Examples:   km/s  or km.s-1           W/m2/Hz   or  W.m-2.Hz-1
- - the list includes about 50 basic unit symbols: SI, IAU extensions, atomic
  physics extensions (sorry, CGS units are excluded!)
Despite of the large number of tables examined, we never found any necessity
to introduce non-integer powers or functions of units like e.g.  log(K)
to express "logarithm of Kelvin" --- and in fact log(K) is rather a scale,
not a physical unit!
Besides the question of units, the document also addresses other conventions,
like a simple way of designating related columns (typically a value and
its related error)
Any comment, suggestion, etc would be appreciated !
Francois Ochsenbein / CDS Strasbourg, France
================================================================================
Document on the "Astronomical Catalogues at CDS: Adopted Standards"
is available on URL ftp:://cdsarc.u-strasbg.fr/pub/cats/doc.ps
                    (TeX and dvi versions also available)
Hundreds of asatronomical catalogues at URL
		    http:://cdsweb.u-strasbg.fr/Cats.html
================================================================================
        _/_/_/_/_/_/ . . .             Centre de Donnees astronomiques de
      _/                               Strasbourg
     _/                                http://cdsweb.u-strasbg.fr/CDS.html
    _/        _/_/  _/_/_/
   _/      _/      _/    _/            Francois Ochsenbein
    _/_/_/_/      _/    _/_/_/_/       Internet: francois at simbad.u-strasbg.fr
         _/      _/    _/      _/         Phone: +33 88 35 84 11
          _/_/  _/_/_/        _/            Fax: +33 88 25 01 60
                             _/            Post: Observatoire Astronomique
                            _/                   11, rue de l'Universite
        . . . _/_/_/_/_/_/_/                     67000 STRASBOURG, France
================================================================================
------- end -------
From fitsbits-request  Mon Sep 19 16:50:45 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1001" "" "19" "September" "1994" "17:21:50" "GMT" "Andy J Kozubal" "kozubal at sst10b.lanl.gov" nil "21" "Conversion between OODB and FITS formats" "^From:" nil nil "9" nil nil (number " " mark "     Andy J Kozubal    Sep 19   21/1001  " thread-indent "\"Conversion between OODB and FITS formats\"\n") nil]
	nil)
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From: kozubal at sst10b.lanl.gov (Andy J Kozubal)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Conversion between OODB and FITS formats
Date: 19 Sep 1994 17:21:50 GMT
Does anyone have any experience using an object-oriented database
(OODB) to store astrophysics data?  Are there any programs or
functions available to convert between OODB formats  and FITS
format?
I just started on a project that will use FITS to store data
from X-ray cameras.  We will eventually have 100's of GBytes
that will be on-line in hundreds of files.  Maintaining
these files seems like a formidable task, so I'm looking for
some tools to help keep things manageable.  One possibility
is to use the organizing capability of an OODB.  I have never used
FITS before, and I am still a novice to OODBs (I do have lots
of experience with relational DB systems).
Thanks,
-----------------------------------------------------------------------
Andy Kozubal                    | Mail Stop D440
Phone: (505) 665-7724           | Los Alamos National Laboratory
E-mail: AKozubal at lanl.gov       | Los Alamos, New Mexico 87545
-----------------------------------------------------------------------
From fitsbits-request  Thu Sep 22 16:50:51 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["755" "" "22" "September" "1994" "19:40:50" "GMT" "William Thompson" "thompson at orpheus.gsfc.nasa.gov" nil "18" "Modified Julian Day" "^From:" nil nil "9" nil nil (number " " mark "     William Thompson  Sep 22   18/755   " thread-indent "\"Modified Julian Day\"\n") nil]
	nil)
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Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
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From: thompson at orpheus.gsfc.nasa.gov (William Thompson)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Modified Julian Day
Date: 22 Sep 1994 19:40:50 GMT
I've been hearing lately that the IAU either has, or is about to, "outlaw" the
use of Modified Julian Day numbers.  Can anyone shed some light on this?
The SoHO/CDS software library contains IDL software to convert between various
time formats (URL ftp://idlastro.gsfc.nasa.gov/contrib/thompson/time).  The
so-called "internal" uses MJD numbers to store the date information.  This is
convenient, because one can easily convert this into various civilian date
formats, using equations from the Astronomical Almanac Supplement.
Is there such a ban in place now, or is it simply being considered?  Would it
apply to internal formats within software, or only to external use such as
publications and (e.g. FITS) data files?
Thank you,
William Thompson
From fitsbits-request  Thu Sep 22 17:31:16 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["2922" "Thu" "22" "September" "1994" "21:31:00" "GMT" "Don Wells" "dwells at nrao.edu" nil "76" "Announcement -- WCS BOF at ADASS'94" "^From:" nil nil "9" nil nil (number " " mark "     Don Wells         Sep 22   76/2922  " thread-indent "\"Announcement -- WCS BOF at ADASS'94\"\n") nil]
	nil)
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From: dwells at nrao.edu (Don Wells)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Announcement -- WCS BOF at ADASS'94
Date: Thu, 22 Sep 1994 21:31:00 GMT
			     Announcment:
		World Coordinate Systems [WCS] Session
			  to be held at the
			  ADASS'94 FITS BOF
		      19:00 Monday 26 September
There will be a FITS BOF [Birds-Of-a-Feather] session on Monday
evening at ADASS'94 (Omni Inner Harbor Hotel, Baltimore, Maryland).
The first item on the agenda will be World Coordinate Systems [WCS].
The WCS portion of the BOF will last no more than one hour,
with at least half an hour reserved for other FITS topics.
The first speaker on WCS will be Eric Greisen, who will introduce the
subject by giving an overview of and answering questions about the
current draft proposal, which can be fetched from:
       ftp://fits.cv.nrao.edu/fits/documents/wcs/wcs.all.ps.Z
All astronomical computing people who are interested in the problem of
associating celestial coordinate information with astronomical digital
imagery should attend the first hour of this FITS BOF session.
The second WCS speaker will be Doug Tody, who will discuss the IRAF
WCS implementation, and will describe the AIPS<-->IRAF WCS
interoperability tests which he and Eric performed in August.
The remainder of the hour will be available for reports of other WCS
implementations, answering technical questions, etc. Anyone who would
like to give brief informal discussion of WCS matters should contact
me so that time can be reserved.
If there are people who will not be attending ADASS'94, but who wish
to contribute to this session, I will be pleased to receive Email from
them and will read or summarize their messages during the session.
			-=- Sample Imagery -=-
I have created a directory for samples of FITS files which have WCS
information in their headers:
	     ftp://fits.cv.nrao.edu/fits/sampledata/wcs/
The initial contents of this directory are:
     311040 Sep 22 16:44 m82opt.fits
      11726 Sep 22 16:52 m82opt.lst
     305280 Sep 22 16:45 m82rad.fits
       5553 Sep 22 16:54 m82rad.lst
     538560 Sep 22 16:44 ngc1316o.fits
       6891 Sep 22 16:56 ngc1316o.lst
     538560 Sep 22 16:44 ngc1316r.fits
       7538 Sep 22 16:57 ngc1316r.lst
The files in this directory use FITS syntactic and semantic
conventions which are upwardly compatible with those described in the
draft document ftp://fits.cv.nrao.edu/fits/documents/wcs/wcs.all.ps.Z.
The *.lst files are listings of the FITS headers. The pairs of radio
and optical imagery have been re-gridded so that they are suitable for
'blink' comparison. One pair uses the 'ARC' projection, the other uses
'SIN'. Both IRAF and AIPS can interpret the coordinate information in
these headers.
I will be delighted to receive additional examples of WCS usage.
--
  Donald C. Wells         Associate Scientist         dwells at nrao.edu
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA
From fitsbits-request  Fri Sep 23 16:32:59 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["573" "Fri" "23" "September" "1994" "14:38:01" "" "Andrew J. P. Maclean" "a.maclean at uws.edu.au" nil "14" "AIPS++" "^From:" nil nil "9" nil nil (number " " mark "     Andrew J. P. Macl Sep 23   14/573   " thread-indent "\"AIPS++\"\n") nil]
	nil)
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Message-Id: <a.maclean.162.000EA2A3 at uws.edu.au>
Organization: University of Western Sydney
Path: saips.cv.nrao.edu!hearst.acc.Virginia.EDU!concert!gatech!udel!MathWorks.Com!zombie.ncsc.mil!gmi!msuinfo!harbinger.cc.monash.edu.au!news.cs.su.oz.au!metro!ob1.uws.edu.au!uws.edu.au!a.maclean
From: a.maclean at uws.edu.au (Andrew J. P. Maclean)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: AIPS++
Date: Fri, 23 Sep 1994 14:38:01
Does anyone know where I can locate the AIPS++ library for manipulating FITS
files?
+----------------------------------+-------------------------------+
|  Andrew J. P. Maclean            |                               |
|  University Planner              |                               |
|  University of Western Sydney    |  Ph:     +61 (02) 678 7848    |
|  PO Box 1000, St Marys, NSW 2760 |  Fax:    +61 (02) 678 7804    |
|  Australia                       |  e-mail: a.maclean at uws.edu.au |
+----------------------------------+-------------------------------+
From fitsbits-request  Sun Sep 25 20:20:07 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["492" "Mon" "19" "September" "1994" "20:19:00" "+0200" "Georg Dittie" "G.DITTIE at CL-HH.comlink.de" nil "15" "Suitable way to detect three color images in FITS ?" "^From:" nil nil "9" nil nil (number " " mark "     Georg Dittie      Sep 19   15/492   " thread-indent "\"Suitable way to detect three color images in FITS ?\"\n") nil]
	nil)
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From: G.DITTIE at CL-HH.comlink.de (Georg Dittie)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Suitable way to detect three color images in FITS ?
Date: Mon, 19 Sep 1994 20:19:00 +0200
Hi to all experienced...
Is there a suitable way to detect automatically if a three dimensional
FITS image is a color image and not a image series ? One way could be to
look at the unit specification of dimension three (=3 color channels) or
dimension one (RGB-Triple) or an identification with the keyword COMMENT.
Which way is used most often ?
Thank you for a short hint. I couldnt find anything about this matter in
the official FITS-Doku.
Georg.
## CrossPoint v3.02 R ##
From fitsbits-request  Tue Sep 27 17:31:37 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["1661" "Tue" "27" "September" "1994" "21:30:21" "GMT" "Don Wells" "dwells at nrao.edu" nil "36" "Re: Modified Julian Day" "^From:" nil nil "9" nil nil (number " " mark "     Don Wells         Sep 27   36/1661  " thread-indent "\"Re: Modified Julian Day\"\n") nil]
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References: <35smk2$j2m at paperboy.gsfc.nasa.gov>
From: dwells at nrao.edu (Don Wells)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: Modified Julian Day
Date: Tue, 27 Sep 1994 21:30:21 GMT
[this followup was posted to sci.astro.research:]
From: aty at ucssun1.sdsu.edu (young a t)
Newsgroups: sci.astro.research
Subject: Re: Modified Julian Day
Date: 26 Sep 1994 09:35:45 -0500
Organization: San Diego State University
In article <35t02e$5v at pecos.msfc.nasa.gov>,
William Thompson <thompson at orpheus.gsfc.nasa.gov> wrote:
>
>I've been hearing lately that the IAU either has, or is about to, "outlaw" the
>use of Modified Julian Day numbers.  Can anyone shed some light on this?
At the recent General Assembly in The Hague, the IAU adopted a resolution
that effectively cancelled an earlier one that recommended the use of MJD.
The basic problem was that the previously adopted MJD (which was itself an
attempt to clear up the confusion among several modifications of the full
Julian Day count then in use) had led to further confusion.
The long and the short of it seems to be that one should stick to the full
JD number, instead of leaving off 2,400,000 or 2,400,000.5 or any other
quantity.  "Modified" Julian Day has turned out to be so prone to confusion
and error that we are all better off to use plain vanilla JD.  If you
absolutely *must* truncate the first 2 digits, explain that what you are using
is JD - 2,400,000 and *don't* try to call it MJD.
--
A.T.Young                      aty at mintaka.sdsu.edu
Astronomy Department
San Diego State University
San Diego CA 92182-0540
--
  Donald C. Wells         Associate Scientist         dwells at nrao.edu
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA
From fitsbits-request  Thu Sep 29 17:49:44 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["2997" "Thu" "29" "September" "1994" "21:48:46" "GMT" "Don Wells" "dwells at nrao.edu" nil "64" "Re: Modified Julian Day" "^From:" nil nil "9" nil nil (number " " mark "     Don Wells         Sep 29   64/2997  " thread-indent "\"Re: Modified Julian Day\"\n") nil]
	nil)
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References: <35smk2$j2m at paperboy.gsfc.nasa.gov>
From: dwells at nrao.edu (Don Wells)
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Subject: Re: Modified Julian Day
Date: Thu, 29 Sep 1994 21:48:46 GMT
[Here is yet another of Andy Young's followups in sci.astro.research -Don]
From: aty at ucssun1.sdsu.edu (young a t)
Newsgroups: sci.astro.research
Subject: Re: Modified Julian Day
Date: 28 Sep 1994 09:52:11 -0500
Organization: San Diego State University
Message-ID: <36bvur$2p6 at pecos.msfc.nasa.gov>
References: <35t02e$5v at pecos.msfc.nasa.gov> <366m81$1oo at pecos.msfc.nasa.gov> <367ekq$1vr at pecos.msfc.nasa.gov>
In article <367ekq$1vr at pecos.msfc.nasa.gov>,
Joe Cain <cain at geomag.gly.fsu.edu> wrote:
>In article <366m81$1oo at pecos.msfc.nasa.gov> aty at ucssun1.sdsu.edu writes:
>>In article <35t02e$5v at pecos.msfc.nasa.gov>,
>>William Thompson <thompson at orpheus.gsfc.nasa.gov> wrote:
...
>We have been using MJD = JD - 2400000.5 for about 30 years in
>geophysics and don't see any reason to change so long as the
>definition is clear. We picked it up from SAO when first starting to
>put times on data and found that one CDC word in binary was good to a
>millisecond. Now we have to use some other means to store in the
>shorter words of "modern" platforms. It is better than the "Julian
>Day" generally used by NASA orbital mechanics which only means the day
                        ^^^^^^^^^^^^^^^^^^^^^^
(and UNIX programmers...)
>of that year.
> How about instead just defining MJD as such and keep it as a useful
>concept for many purposes? Most people don't like the idea of a day
That was what the IAU tried some years ago.  The main problem was caused
by the half day, because the variable-star folks had been using JD - 2400000
(no half day) for a long time.  The result was that people started calling
(JD - 2400000) "MJD" and thus not following the IAU-approved definition.
This year, the IAU gave it up as a bad job; not enough users have the necessary
discipline to keep to the definition.
>... Most people don't like the idea of a day
>starting at noon except for astronomers ....
Well, most people don't like time tied to Greenwich unless they live near
England.  The half day was for the convenience of European astronomers
back in the last century; I'm not sure when that half-day offset from
Greenwich time was introduced.  It was officially abandoned by astronomers
in 1925, when we went from GMAT to UT as the standard.  But, to avoid
confusion, the JD count continued to change at Greenwich Mean Noon.
You are, of course, welcome to continue using MJD *if* you keep your
readers informed of what you mean by it.  It's just no longer approved
by the IAU as an astronomical standard.  Like Prohibition, it looked
like a good idea at one time, but did not work out well in practice....
--
A.T.Young                      aty at mintaka.sdsu.edu
Astronomy Department
San Diego State University
San Diego CA 92182-0540
--
  Donald C. Wells         Associate Scientist         dwells at nrao.edu
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA
From fitsbits-request  Fri Sep 30 09:02:51 1994
Status: RO
X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil]
	["5124" "Fri" "30" "September" "1994" "09:02:46" "-0400" "Arnold Rots" "arots at xebec.gsfc.nasa.gov" nil "106" "Re: Modified Julian Day" "^From:" nil nil "9" nil nil (number " " mark "     Arnold Rots       Sep 30  106/5124  " thread-indent "\"Re: Modified Julian Day\"\n") nil]
	nil)
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From: Arnold Rots <arots at xebec.gsfc.nasa.gov>
Sender: fitsbits-request at fits.CV.NRAO.EDU
To: fitsbits at fits.CV.NRAO.EDU
Cc: arots at xebec.gsfc.nasa.gov
Subject: Re: Modified Julian Day
Date: Fri, 30 Sep 1994 09:02:46 -0400
> [Here is yet another of Andy Young's followups in sci.astro.research -Don]
> From: aty at ucssun1.sdsu.edu (young a t)
> Newsgroups: sci.astro.research
> Subject: Re: Modified Julian Day
> Date: 28 Sep 1994 09:52:11 -0500
> Organization: San Diego State University
> Message-ID: <36bvur$2p6 at pecos.msfc.nasa.gov>
> References: <35t02e$5v at pecos.msfc.nasa.gov> <366m81$1oo at pecos.msfc.nasa.gov> <367ekq$1vr at pecos.msfc.nasa.gov>
> In article <367ekq$1vr at pecos.msfc.nasa.gov>,
> Joe Cain <cain at geomag.gly.fsu.edu> wrote:
> >In article <366m81$1oo at pecos.msfc.nasa.gov> aty at ucssun1.sdsu.edu writes:
> >>In article <35t02e$5v at pecos.msfc.nasa.gov>,
> >>William Thompson <thompson at orpheus.gsfc.nasa.gov> wrote:
> ...
> >We have been using MJD = JD - 2400000.5 for about 30 years in
> >geophysics and don't see any reason to change so long as the
> >definition is clear. We picked it up from SAO when first starting to
> >put times on data and found that one CDC word in binary was good to a
> >millisecond. Now we have to use some other means to store in the
> >shorter words of "modern" platforms. It is better than the "Julian
> >Day" generally used by NASA orbital mechanics which only means the day
>                         ^^^^^^^^^^^^^^^^^^^^^^
> (and UNIX programmers...)
> >of that year.
> > How about instead just defining MJD as such and keep it as a useful
> >concept for many purposes? Most people don't like the idea of a day
> That was what the IAU tried some years ago.  The main problem was caused
> by the half day, because the variable-star folks had been using JD - 2400000
> (no half day) for a long time.  The result was that people started calling
> (JD - 2400000) "MJD" and thus not following the IAU-approved definition.
> This year, the IAU gave it up as a bad job; not enough users have the necessary
> discipline to keep to the definition.
It looks very much like the tail wagging the dog.  To me it appears as
though a tiny segment of the community couldn't muster the discipline
to call their deviant definition something else and, after having
caused confusion in their own circles (there are variable star people
who do use the proper definition of MJD), possibly out of spite, force
everbody to abandon a useful concept.
This decision to recant is even worse, since most of the community is
not going to change what they have been doing for years, acting as if
it still is an IAU-blessed unit, while in reality it isn't (speaking
of confusion!).
There are too many FITS files out with MJD, there is too much software
that uses it.  The variable star folks will have to face reality and
acknowledge that even an IAU decision can't keep the community from
using the former IAU-condoned definition of MJD.
> >... Most people don't like the idea of a day
> >starting at noon except for astronomers ....
> Well, most people don't like time tied to Greenwich unless they live near
> England.  The half day was for the convenience of European astronomers
> back in the last century; I'm not sure when that half-day offset from
> Greenwich time was introduced.  It was officially abandoned by astronomers
> in 1925, when we went from GMAT to UT as the standard.  But, to avoid
> confusion, the JD count continued to change at Greenwich Mean Noon.
I rather suspect that the half day offset originated from nautical
practice to start the day at noon: that was the moment in the day that
all important things happened, with noon sightings of the sun and
taking the nautical almanac from the shelf - determining the elevation
of the sun at midnight is too problematic.
> You are, of course, welcome to continue using MJD *if* you keep your
> readers informed of what you mean by it.  It's just no longer approved
> by the IAU as an astronomical standard.  Like Prohibition, it looked
> like a good idea at one time, but did not work out well in practice....
Unlike prohibition, it _was_ a good idea ...
I'm sure this was pretty much a storm in a teacup.  FITS files will
continue to carry MJD - perhaps with an extra comment - and most
astronomical software will continue to use it.
What may need to be stressed, though, is that using MJD (or JD, for
that matter) for defining a moment in absolute time requires not only
an MJD value that includes a fractional part, but also an indication
what time system is being used.  The Julian Day is not tied to any
particular time system (UTC, TAI, TT, ...), it only provides a
formalism for counting calendar days within such a time system.  For
instance, the epoch 1994.0 (UTC) (January 1, 1994 at 00:00:00 UTC, or
MJD=49352.0 (UTC)), is at MJD=49352.000696574074 (TT).  Very seldom
does one see a time system identified when MJD is given.
> -- > A.T.Young aty at mintaka.sdsu.edu
> Astronomy Department
> San Diego State University
> San Diego CA 92182-0540
> --
>   Donald C. Wells         Associate Scientist         dwells at nrao.edu
>                     http://fits.cv.nrao.edu/~dwells
>   National Radio Astronomy Observatory                +1-804-296-0277
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