Starlink User Note 190.11
4th November 2001
Copyright © 2001 Council for the Central Laboratory of the Research Councils
Catalogue and Table Manipulation Applications
CURSA is a package of Starlink applications for manipulating astronomical catalogues and similar tabular datasets. It provides facilities for: browsing or examining catalogues, selecting subsets from a catalogue, sorting catalogues, copying catalogues, pairing two catalogues, converting catalogue coordinates between some celestial coordinate systems, plotting finding charts and photometric calibration. Also, subsets can be extracted from a catalogue in a format suitable for plotting using other Starlink packages, such as PONGO. CURSA can access catalogues held in the popular FITS table format, the Tab-Separated Table (TST) format or the Small Text List (STL) format. Catalogues in the STL and TST formats are simple ASCII text files. CURSA also includes some facilities for accessing remote on-line catalogues via the Internet.
This manual describes how to use Version 6.4 of CURSA. Its intended readership is users and potential users of CURSA.
CURSA Quick Reference
To set up for using CURSA type:
| ||browse and generate selections from a catalogue (X-windows, easy-to-use),|
| ||browse and generate selections from a catalogue (command line),|
| ||select a subset from a catalogue,|
| ||convert between celestial coordinate systems,|
| ||plot a finding chart,|
| ||set up ready for plotting a finding chart,|
| ||list various header information for a catalogue,|
| ||copy a catalogue,|
| ||sort a catalogue,|
| ||pair two catalogues,|
| ||bin one, two or three columns into a histogram, image or data cube,|
| ||define photometric transformation coefficients,|
| ||apply photometric transformation coefficients to programme objects,|
| ||list photometric transformation coefficients,|
| ||convert a CDS text catalogue to STL format,|
| ||convert a region in the HST Guide Star Catalog to a more convenient format,|
| ||access remote on-line catalogues.|
.FIT .fit .FITS .fits .GSC .gsc). Binary and ASCII FITS tables.
.TAB .tab). The Tab-Separated Table format used by GAIA.
.TXT .txt). The Small Text List format.
+ - * / **
.EQ. .NE. .GE. .GT. .LE. .LT. == /= >= > <= <
logical (boolean) operators:
.AND. .OR. .NOT. &
brackets: use brackets, ‘
)’, as appropriate,
sexagesimal values: use a colon (‘:’) to separate hours/degrees, minutes and seconds. Unsigned values are interpreted as hours; values in degrees must always have a sign (‘
-’). Sexagesimal values are converted to radians prior to evaluating the expression.
great circle distance:
position angle of point from point :
A ‘home page’ giving useful information about CURSA is available via the World Wide Web. Its URL is:
An on-line version of SUN/190 (this manual) is also available via the World Wide Web. On Starlink systems type:
Otherwise access URL:
If you are experiencing difficulties using CURSA then in the first instance you should probably seek advice and assistance from your local site manager. Bug reports should be sent to username:
Bug reports should always be sent to username
firstname.lastname@example.org. However, you are
welcome to contact me directly for advice and assistance. Suggestions for enhancements
and improvements to CURSA are also welcome. Details of how to contact me are given
Postal address: Institute for Astronomy, Royal Observatory, Blackford Hill, Edinburgh,
|EH9 3HJ, United Kingdom.|
|from within the United Kingdom:||0131-668-8416|
CURSA is far from being all my own work. Clive Page, Rodney Warren-Smith and Alan Wood have
all been involved in aspects of its development. Indeed, Clive Page wrote the expression parser which
CURSA uses, and Appendix A is based on documentation which he supplied. Malcolm Currie and
Anne Sansom tested an early version of
xcatview and suggested several significant improvements.
Numerous other people have made useful contributions.
I am grateful to everyone who has contributed time and expertise.
Department of Physics and Astronomy, University of Leicester
Saint Indract’s Day 1995
Various items of external software have been introduced into version 3.1 of CURSA which it is a
pleasure to acknowledge.
catremote accesses remote on-line catalogues using the catlib library
developed by Allan Brighton, Miguel Albrecht and colleagues at the European Southern
Observatory. Patrick Wallace gave useful advice and assistance during the development of
catcoord and this application uses his SLA library to convert between celestial coordinate
catchart uses Tim Pearson’s PGPLOT to produce its plots. Last, but not least,
FITS tables continue to be accessed using Bill Pence’s invaluable FITSIO library. I am also
grateful to the numerous people who have commented on, and suggested improvements to,
Institute for Astronomy, University of Edinburgh
Saint Médard’s Day 1997
I am grateful to John Lucey for useful discussions about photometric calibration and for kindly providing the data used in the example catalogue of observations of photometric standard stars. Peter Draper gave helpful comments on the section of the manual describing the photometric calibration.
Institute for Astronomy, University of Edinburgh
Saint Aed’s Day 1997
catcdsinand additional formats for reading sexagesimal angles from fixed-format STL catalogues (ACD).
catgridand options for plotting scatter-plots and histograms in
catchart. The facilities to access remote catalogues via the Internet have been completely re-worked. A ‘quiet mode’ has been added to most of the applications. Support for the little-used CHI/HDS catalogue format has been removed.
catheaderhas been re-worked and now offers various options and more convenient output. A bug in
xcatviewhas been fixed.
 M. Albrecht, M. Barylak, D. Durand, P. Fernique, A. Micol, F. Ochsenbein,
F. Pasian, B. Pirenne, D. Ponz and M. Wenger, 19 September 1996, Astronomical Server
URL (Version 1.0). See URL:
 D.S. Berry, G.J. Privett and A.C. Davenhall, 15 September 1997, SUN/203.3: SX & DX — IBM Data Explorer for Data Visualisation, Starlink.
 M.J. Currie and D.S. Berry, 20 October 2000, SUN/95.16: KAPPA – Kernel Application Package, Starlink.
 M.J. Currie, G.J.Privett, A.J.Chipperfield, D.S. Berry and A.C. Davenhall, 21 September 2000, SUN/55.14: CONVERT — A Format-conversion Package, Starlink.
 A.C. Davenhall, 18 March 1993, SUN/162.1: A Guide to Astronomical Catalogues, Databases and Archives available through Starlink, Starlink.
 A.C. Davenhall, 1 October 1997, SC/2.3: The DX Cookbook, Starlink.
 A.C. Davenhall, 26 July 2000, SSN/75.1: Writing Catalogue and Image Servers for GAIA and CURSA, Starlink.
 A.C. Davenhall, 4 April 2001, SUN/181.10: CAT — Catalogue and Table Manipulation Library: Programmer’s Manual, Starlink.
 A.C. Davenhall, 24 May 2001, SSN/76.1: CATREMOTE — a Tool for Querying Remote Catalogues, Starlink.
 P.W. Draper and N. Gray, 16 October 2000, SUN/214.8: GAIA — Graphical Astronomy and Image Analysis Tool, Starlink.
 P.W. Draper and N. Eaton, 24 May 1999, SUN/109.10: PISA – Position Intensity and Shape Analysis, Starlink.
 N. Eaton, P.W. Draper and A. Allan, 15 November 1999, SUN/45.10: PHOTOM – A Photometry Package, Starlink.
 R.H. Hardie, 1962, Photoelectric Reductions, Chapter 8 of Astronomical Techniques, ed. W.A. Hiltner, Stars and Stellar Systems, II (University of Chicago Press: Chicago), pp178-208. See especially p180.
 P. Harrison, P. Rees and P. Draper, 12 November 1997, SUN137.6: PONGO – A Set of Applications for Interactive Data Plotting, Starlink.
 H. Meyerdierks, D.S. Berry, P.W. Draper, G.J. Privett and M.J. Currie, 14 February 1997, SUN/194.2: PDA — Public Domain Algorithms, Starlink.
 D. Monet, A. Bird, B. Canzian, H. Harris, N. Reid, A. Rhodes, S. Sell, H. Ables,
C. Dahn, H. Guetter, A. Henden, S. Leggett, H. Levison, C. Luginbuhl, J. Martini,
A. Monet, J. Pier, B. Riepe, R. Stone, F. Vrba and R. Walker, 1996, USNO-SA1.0, (U.S.
Naval Observatory: Washington DC). See also URL:
 F. Ochsenbein, 12 September 1994, Astronomical Catalogues at CDS: Adopted Standards, version 1.4, p14. Available on-line from the CDS (see Section 2).
 J. Palmer and A.C. Davenhall, 31 August 2001, SC/6.4: The CCD Photometric Calibration Cookbook, Starlink.
 K.T. Shortridge, H. Meyerdierks, M.J. Currie, M.J. Clayton, J. Lockley, A.C. Charles, A.C. Davenhall, M.B. Taylor, T. Ash, T. Wilkins, D. Axon, J. Palmer, A. Holloway and V. Graffagnino, 31 October 2001, SUN/86.19: FIGARO — A General Data Reduction System, Starlink.
 D.L. Terrett and N. Eaton, 12 July 1995, SUN/57.8: GNS – Graphics Workstation Name Service, Starlink.
 P.T. Wallace, 21 June 1995, SUN/56.10: COCO — Conversion of Celestial Coordinates, Starlink.
 P.T. Wallace, 17 October 2000, SUN/67.51: SLALIB — Positional Astronomy Library, Starlink.
 R.F. Warren-Smith, 11 January 2000, SUN/33.7: NDF — Routines for Accessing the Extensible N-Dimensional Data Format, Starlink.
 R.F. Warren-Smith and D.S. Berry, 23 May 2000, SUN/210.7: AST — A Library for Handling World Coordinate Systems in Astronomy (Fortran Version), Starlink.
 R.F. Warren-Smith and D.S. Berry, 23 May 2000, SUN/211.7: AST — A Library for Handling World Coordinate Systems in Astronomy (C Version), Starlink.