= Starlink =

The Starlink Project was a long running UK Project supporting astronomical data processing. It was shut down in 2005 but the software continued to be developed at the Joint Astronomy Centre until March 2015, and is now maintained by the [[https://www.eaobservatory.org/ | East Asian Observatory]]. The code is open source.

[[StarlinkNews | Starlink News ]] was last updated 2023-12-20.

== Getting the Software ==

The Joint Astronomy Centre and East Asian Observatory have made a number of [[Releases | releases]]. The most recent is [[2023A]] which can be downloaded from [[2023ADownload | here]] where installation instructions are also provided.

'''Please note that there was a leap second at the end of December 2016; data taken since then will be gridded wrongly by all releases prior to [[2016A]].  Please use [[2023A]] (or [[2021A]], [[2018A]], [[2016A]], or a development rsync version) to reduce JCMT data taken from this point onwards.'''

For a cutting edge version, you can sometimes [[rsyncStarlink|rsync from the East Asian Observatory's build]].


== Citing the software ==
If you have used Starlink software in your research, please cite the software in your papers.

For the Starlink software package please use:
 * Starlink citation: Currie et al. 2014 [[https://ui.adsabs.harvard.edu/#abs/2014ASPC..485..391C/abstract|2014ASPC..485..391C]]
 * Starlink acknowledgment: “The Starlink software (Currie et al 2014) is currently supported by the East Asian Observatory.” 

Most recent reference:
 * Berry et al. 2022 [[https://ui.adsabs.harvard.edu/abs/2022ASPC..532..559B/abstract|2022ASPC..532..559B]]

All of the individual packages are on the Astronomy Source Code Library, which have entries in ADS and can be cited in major astronomy journals. If a package has no other reference, please cite the ASCL entry. The following packages have a preferred reference you should use instead or as well as the ASCL entry (links are to the ADS record for the reference):

 * SMURF: For makemap (SCUBA-2 DR) please cite https://adsabs.harvard.edu/abs/2013MNRAS.430.2545C
          For makecube (heterodyne/ACSIS DR) please cite https://adsabs.harvard.edu/abs/2015MNRAS.453...73J
 * CUPID: [[https://adsabs.harvard.edu/abs/2007ASPC..376..425B|2007ASPC..376..425B]]
 * The !FellWalker algorithm (implemented inside Cupid's clumpfind) has its own citation: [[https://adsabs.harvard.edu/abs/2015A%26C....10...22B|2015A&C....10...22B]] Berry, D S 2015 "!FellWalker-A clump identification algorithm" in Astronomy and Computing 

 * SPLAT-VO ascl:1402.007 prefers [[https://adsabs.harvard.edu/abs/2014A&C.....7..108S|2014A&C.....7..108S]]
 * SPLAT: ascl:1402.008
 * NDF: http://ascl.net/1411.023 prefers:  [[https://adsabs.harvard.edu/abs/2015A&C....12..146J|2015A&C....12..146J]]
 * PAL: http://ascl.net/1606.002 prefers: https://adsabs.harvard.edu/abs/2013ASPC..475..307J
 * SURF: ascl:1403.008 prefers https://adsabs.harvard.edu/abs/1998ASPC..145..216J
 * AST: ascl:1404.016 prefers https://adsabs.harvard.edu/abs/2016A&C....15...33B
 * SLALIB: ascl:1403.025 prefers https://adsabs.harvard.edu/abs/1994ASPC...61..481W

In addition, all Starlink SUNs also have bibliographic records on ADS.



== Getting Support ==

The original [[https://www.starlink.ac.uk |Starlink]] web site has been mothballed but additional support can be found:

 * [[https://starlink.eao.hawaii.edu/cgi-bin/htxfinder | Search the documentation]]

 * For questions about JCMT data reduction please see [[ https://www.eaobservatory.org/jcmt/help | the JCMT help desk ]]

 * For other questions about any of the Starlink software (e.g. installation issues, software bugs or other errors) please use the [[http://www.jiscmail.ac.uk/archives/starlink.html | Starlink support mailing list ]]


There is also information on the [[http://en.wikipedia.org/wiki/Starlink_Project | Starlink wikipedia entry]].

== Support Pages for Starlink Applications and Libraries ==

Some Starlink applications and libraries have associated support pages:

 * [[ AST ]]
 * [[ CUPID ]]
 * [[ https://www.eao.hawaii.edu/oracdr/ | ORAC-DR ]]
 * [[ http://star-www.dur.ac.uk/~pdraper/splat/splat-vo/splat-vo.html| SPLAT ]]

== Developing and Building the software ==

The source code is freely available. Development and build questions can be asked on the [[ http://www.jiscmail.ac.uk/archives/stardev.html | Starlink development mailing list]]

The source code is directly available from a Git [[https://github.com/Starlink | source code repository]]. Download the source code:

{{{
 % git clone https://github.com/Starlink/starlink.git
}}}

You can download Git from [[http://git-scm.com/ | its home page]]. A [[GitPrimer | Git primer]] is available along with the Starlink [[GitPolicies | Git development policies]]. The bulk of the collection is distributed under the [[http://www.gnu.org/licenses/gpl.txt|GNU Public Licence]], and the remainder under the [[StarlinkLicence |old Starlink Licence]].

The README file in the top level of the source code contains instructions for building. Please also see [[BuildingStarlinkOnOSX | Building Starlink on macOS]] for some macOS tips (including a build script and list of dependencies).

Refer to the code in individual packages for more information.

We are trying to write new code in C rather than Fortran since this gives us much more flexibility in terms of threading and compilers. If you are a Fortran programmer familiar with Starlink programming [[StarlinkCProgramming | some useful hints are available]]. 

Primarily for local consumption, we also have a [[StarlinkRelease|list of steps to take when making a release]].


== EAO and its plans for Starlink in the future (2018-07) ==

East Asian Observatory does not anticipate moving away from NDF and
Starlink for its data format and astronomy software. We have therefore
been working to ensure Starlink will still be fit-for-purpose over the
next years as we upgrade the instrumentation at the JCMT. The current
work has focused on:

 * moving to HDS version 5, using the standard HDF5 file format. This
allows the larger array sizes necessary with large-format heterodyne
instruments.

 * Porting critical libraries and applications from F77 to C, to
remove single-thread bottlenecks and allow for long-term
maintainability. ARY has been finished in the 2018A release, and NDF
is currently being converted.

We would also like to acknowledge the continuing help and support provided by the wider Starlink developer and user communities, and reiterate our continued support of Starlink as an open source project.

We recognize that currently the most popular scripting language among
our users is Python, and we are continuing to look at the best ways to
allow easy use of NDF and Starlink from Python, and improving
interoperability with the wider astronomical python community.
Currently, there are existing HDS and NDF python interfaces, the PyAst
package, and the starlink-pywrapper package to enable easy calling of Starlink routines from Python.


== History ==

If you are interested in the history of Starlink there is a lot of documentation available.

 * The [[Bulletins | Starlink Bulletin]] was published between January 1988 and August 2004.

 * [[ https://starlink.eao.hawaii.edu/bulletins/fac1996.pdf | Starlink Software Facilities brochure 1996 ]].

 * [[ https://starlink.eao.hawaii.edu/bulletins/brochure1994.pdf | Starlink Brochure 1994 ]].

 * The [[Chronicle | Starlink Chronicle]] logged notable events and staff changes.

 * The former Atlas laboratory has a [[http://www.chilton-computing.org.uk/acd/starlink/overview.htm | photographic record]] of the early days of its Starlink node, and of the Starlink inauguration.  There is also an overview and summary of the genesis of Starlink.