Starlink Project
Encyclopedia
The Starlink Project, referred to by users as Starlink and by developers as simply The Project, was a UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
astronomical
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
computing project which supplied general-purpose data reduction software. Until the late nineties, it also supplied computing hardware and system administration personnel to UK astronomical institutes. In the former respect at least, it was analogous to the US
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
IRAF
IRAF
IRAF is a collection of software written at the National Optical Astronomy Observatory geared towards the reduction of astronomical images in pixel array form. This is primarily data taken from imaging array detectors such as CCDs...
project, with which it long maintained a friendly rivalry.
The Project was formally started in 1980, though the funding had been agreed, and some work begun, a year earlier. It was closed down when its funding was withdrawn by PPARC
Particle Physics and Astronomy Research Council
The Particle Physics and Astronomy Research Council was one of a number of Research Councils in the United Kingdom. It directed, coordinated and funded research in particle physics and astronomy for the people of the UK...
in 2005. In 2006 the Joint Astronomy Centre
Joint Astronomy Centre
The Joint Astronomy Centre operates British, Canadian and Dutch telescopes at Mauna Kea Observatory, and provides support for other telescopes and public outreach activities...
released its own updated version of Starlink and took over maintenance; the latest version was released on 20 January 2010.
History
From its beginning, the project aimed to cope with the ever-increasing data volumes which astronomers had to handle. A 1982 paper exclaimed that astronomers were returning from observing runs (a week or so of observations at a remote telescope) with more than 10 Gigabits of data on tape; at the end of its life the project was rolling out libraries to handle data of more than 4 Gigabytes per single image.
Joint Astronomy Centre
The Joint Astronomy Centre operates British, Canadian and Dutch telescopes at Mauna Kea Observatory, and provides support for other telescopes and public outreach activities...
, the home of UKIRT and the JCMT
James Clerk Maxwell Telescope
The James Clerk Maxwell Telescope is a submillimetre-wavelength telescope at Mauna Kea Observatory in Hawaii. Its primary mirror is 15 metres across: it is the largest astronomical telescope that operates in submillimetre wavelengths of the electromagnetic spectrum...
in Hawai'i
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
. The number of active developers fluctuated between five and more than a dozen.
By 1982, the project had a staff of 17, serving about 400 users at six sites, using seven VAX
VAX
VAX was an instruction set architecture developed by Digital Equipment Corporation in the mid-1970s. A 32-bit complex instruction set computer ISA, it was designed to extend or replace DEC's various Programmed Data Processor ISAs...
en (six VAX-11/780
VAX-11
The VAX-11 was a family of minicomputers developed and manufactured by Digital Equipment Corporation using processors implementing the VAX instruction set architecture . The VAX-11/780 was the first VAX computer.- VAX-11/780 :...
s and one VAX-11/750
VAX-11
The VAX-11 was a family of minicomputers developed and manufactured by Digital Equipment Corporation using processors implementing the VAX instruction set architecture . The VAX-11/780 was the first VAX computer.- VAX-11/780 :...
, representing a total of about 6.5 GB of disk space). They were networked from the outset, first with DECNET
DECnet
DECnet is a suite of network protocols created by Digital Equipment Corporation, originally released in 1975 in order to connect two PDP-11 minicomputers. It evolved into one of the first peer-to-peer network architectures, thus transforming DEC into a networking powerhouse in the 1980s...
and later with X.25
X.25
X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...
.
Between 1992 and 1995 the project switched to UNIX (and switched the networking to TCP/IP), supporting Digital UNIX on Alpha
DEC Alpha
Alpha, originally known as Alpha AXP, is a 64-bit reduced instruction set computer instruction set architecture developed by Digital Equipment Corporation , designed to replace the 32-bit VAX complex instruction set computer ISA and its implementations. Alpha was implemented in microprocessors...
-based systems, and Solaris
Solaris Operating System
Solaris is a Unix operating system originally developed by Sun Microsystems. It superseded their earlier SunOS in 1993. Oracle Solaris, as it is now known, has been owned by Oracle Corporation since Oracle's acquisition of Sun in January 2010....
on systems from Sun Microsystems
Sun Microsystems
Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
. By the late 1990s it was additionally supporting Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, and by 2005 it was supporting Red Hat Linux
Red Hat Linux
Red Hat Linux, assembled by the company Red Hat, was a popular Linux based operating system until its discontinuation in 2004.Red Hat Linux 1.0 was released on November 3, 1994...
, Solaris, and Tru64 UNIX
Tru64 UNIX
Tru64 UNIX is a 64-bit UNIX operating system for the Alpha instruction set architecture , currently owned by Hewlett-Packard . Previously, Tru64 UNIX was a product of Compaq, and before that, Digital Equipment Corporation , where it was known as Digital UNIX .As its original name suggests, Tru64...
. It was about this time that the Project open-sourced its software (using the GPL
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
; it had previously had an `academic use only' licence), and reworked its build system so that the software could be built on a much broader range of POSIX
POSIX
POSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
-like systems, including Mac OS X
Mac OS X
Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
and Cygwin
Cygwin
Cygwin is a Unix-like environment and command-line interface for Microsoft Windows. Cygwin provides native integration of Windows-based applications, data, and other system resources with applications, software tools, and data of the Unix-like environment...
.
Though it was not explicitly funded to do so, the Project was an early participant in the Virtual Observatory
Virtual Observatory
Virtual observatory is a collection of interoperating data archives and software tools which utilize the internet to form a scientific research environment in which astronomical research programs can be conducted....
movement, and contributed to the IVOA
IVOA
The International Virtual Observatory Alliance or IVOA is a worldwide scientific organisation formed in June 2002. Its mission is to facilitate international coordination and collaboration necessary for enabling global and integrated access to data gathered by astronomical observatories. An...
. Its best-known VO application was TOPCAT, development of which continues, with AstroGrid
AstroGrid
AstroGrid is a £7.7M project which built a data-grid for UK astronomy, forming part of the UK contribution to the International Virtual Observatory. AstroGrid announced its first full production release on 1 April 2008....
funding.
Applications, libraries, and other facilities
The Project produced a number of well-known applications and libraries. Of these, some of the highlights are:GAIA : The main GUI application, which acts as a general astronomical image viewer, as well as a front end to many of the other applications.
ORAC-DR : The ORAC-DR data reduction system, developed at JAC Hawai'i
Joint Astronomy Centre
The Joint Astronomy Centre operates British, Canadian and Dutch telescopes at Mauna Kea Observatory, and provides support for other telescopes and public outreach activities...
, is a data processing pipeline for incoming data. It is in use for online data reduction at UKIRT and JCMT for a variety of instruments. This is not a Starlink application as such, but it is tightly integrated with the Starlink suite, and by default uses Starlink software as its application engines. See the ORAC-DR home page for further details.
KAPPA : A suite of general-purpose data-analysis and visualisation tools, usable both from the command-line and graphically. It provides general-purpose applications that have wide applicability, concentrating on image processing, data visualisation, and manipulating NDF components. It integrates with other Starlink packages. In a wider context, KAPPA offers facilities not in IRAF, for instance handling of data errors, quality masking, a graphics database, availability from the shell, as well as more n-dimensional applications, widespread use of data axes, and a different style. It integrates with instrument packages developed at UK observatories. With the automatic data conversion and the availability of KAPPA and other Starlink packages from within the IRAF
IRAF
IRAF is a collection of software written at the National Optical Astronomy Observatory geared towards the reduction of astronomical images in pixel array form. This is primarily data taken from imaging array detectors such as CCDs...
command language, it's possible to pick the best of the relevant tools from both systems to get the job done.
CCDPACK : A package of programs for reducing CCD
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...
-like data. They allow you to debias, remove dark current, pre-flash, flatfield, register, resample, normalize and combine your data.
AST : A flexible and powerful library for handling World Coordinate Systems, partly based on the SLALIB library. If you are writing software for astronomy and need to use celestial coordinates (e.g. RA and Dec), spectral coordinates (e.g. wavelength, frequency, etc.), or other coordinate system information, then this library should be of interest. It provides solutions for most of the problems you will meet and allows you to write robust and flexible software. It is able to read and write WCS information in a variety of formats, including FITS
FITS
Flexible Image Transport System is a digital file format used to store, transmit, and manipulate scientific and other images. FITS is the most commonly used digital file format in astronomy...
-WCS. It has both Fortran and C bindings.
SLALIB : A library of routines intended to make accurate and reliable positional-astronomy applications easier to write. Most SLALIB routines are concerned with astronomical position and time, but a number have wider trigonometrical, numerical or general applications. As well as this GPL version, there is also a commercial version of SLALIB available from its original author.
HDS : A Hierarchical Data System -- is a portable, flexible system for storing and retrieving data, and takes over from a computer's filing system at the level of an individual file. A conventional file effectively contains an 1-dimensional sequence of data elements, whereas an HDS file can contain a more complex structure. It predates the Hierarchical Data Format
Hierarchical Data Format
Hierarchical Data Format is the name of a set of file formats and libraries designed to store and organize large amounts of numerical data...
by several years.
NDF : NDF is the Project's principal data format. Built upon HDS the N-dimensional Data Format -- is for storing bulk data in the form of n-dimensional arrays of numbers: mostly spectra, images, and cubes. It supports concepts such as quality, data errors, world coordinate systems, and Metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
. It is also extensible to handle user-defined information.
ADAM : The ADAM environment was a standardised software environment developed initially by the RGO, and then adopted and developed by Starlink between 1985 and 1990. It was initially designed as a telescope control system, installed at the AAT
Anglo-Australian Telescope
The Anglo-Australian Telescope is a 3.9 m equatorially mounted telescope operated by the Australian Astronomical Observatory and situated at the Siding Spring Observatory, Australia at an altitude of a little over 1100 m...
at Siding Spring
Siding Spring Observatory
Siding Spring Observatory near Coonabarabran, New South Wales, Australia, part of the Research School of Astronomy & Astrophysics at the Australian National University , incorporates the Anglo-Australian Telescope along with a collection of other telescopes owned by the Australian National...
, the WHT
William Herschel Telescope
The William Herschel Telescope is a optical/near-infrared reflecting telescope located at the Observatorio del Roque de los Muchachos on the island of La Palma in the Canary Islands, Spain. The telescope, which is named after William Herschel, is part of the Isaac Newton Group of Telescopes...
at the ING
Isaac Newton Group of Telescopes
The Isaac Newton Group of Telescopes or ING operates the William Herschel Telescope, Isaac Newton Telescope and Jacobus Kapteyn Telescope optical telescopes for the Science and Technology Facilities Council , the NWO and the IAC...
on La Palma
La Palma
La Palma is the most north-westerly of the Canary Islands. La Palma has an area of 706 km2 making it the fifth largest of the seven main Canary Islands...
, and at the JCMT
James Clerk Maxwell Telescope
The James Clerk Maxwell Telescope is a submillimetre-wavelength telescope at Mauna Kea Observatory in Hawaii. Its primary mirror is 15 metres across: it is the largest astronomical telescope that operates in submillimetre wavelengths of the electromagnetic spectrum...
on Mauna Kea
Mauna Kea Observatory
The Observatories at Mauna Kea, , are an independent collection of astronomical research facilities located on the summit of Mauna Kea on the Big Island of Hawai'i, USA. The facilities are located in a special land use zone known as the "Astronomy Precinct," which is located in the Mauna Kea...
(where it is still working in legacy systems), but its role expanded to cover graphics, data access, interprocess communication, and the full range of functionality required to support a diverse range of interoperable applications. Although it is no longer seriously used for telescope control, other layers of it live on in the current versions of the Starlink applications and libraries.
For fuller details of any of these utilities, see the list of `SUN's on the Starlink Project's documentation page. The Project also produced a number of cookbooks on various astronomical topics.
By the end, the Project's codebase consisted of around 100 components, totalling around 2100kSLOC
Source lines of code
Source lines of code is a software metric used to measure the size of a software program by counting the number of lines in the text of the program's source code...
written by the project or curated by it, in various languages including Fortran, C, C++, Java, Perl and Tcl/Tk, plus another 700kSLOC of customised third-party code. Just to put this in context, David A Wheeler's SLOCCount program would have us believe that that's worth over $100M and, according to his analysis of the RH7.1 distribution , it appears that 2.1MSLOC is larger than anything in that distribution except the kernel, Mozilla and XFree86. The Project was busy.
Obtaining the software
At present, though funding for the Project has ceased, the software is still available, either as prebuilt distributions, or from aGit
Git (software)
Git is a distributed revision control system with an emphasis on speed. Git was initially designed and developed by Linus Torvalds for Linux kernel development. Every Git working directory is a full-fledged repository with complete history and full revision tracking capabilities, not dependent on...
repository: see the Starlink developers' pages.
The Joint Astronomy Centre
Joint Astronomy Centre
The Joint Astronomy Centre operates British, Canadian and Dutch telescopes at Mauna Kea Observatory, and provides support for other telescopes and public outreach activities...
took over the maintenance of the Starlink codebase (with support from STFC
Science and Technology Facilities Council
The Science and Technology Facilities Council is a UK government body that carries out civil research in science and engineering, and funds UK research in areas including particle physics, nuclear physics, space science and astronomy .-History:It was formed in April 2007 as a merger of the Particle...
), and has made the following releases since:
- Keoe (VegaVegaVega is the brightest star in the constellation Lyra, the fifth brightest star in the night sky and the second brightest star in the northern celestial hemisphere, after Arcturus...
) release on 2006 September 7 - Hokulei (CapellaCapella (star)Capella is the brightest star in the constellation Auriga, the sixth brightest star in the night sky and the third brightest star in the northern celestial hemisphere, after Arcturus and Vega. Although it appears to be a single star to the naked eye, it is actually a star system of four stars in...
) release in Spring 2007 March 1 - Puana (ProcyonProcyonProcyon is the brightest star in the constellation Canis Minor. To the naked eye, it appears to be a single star, the seventh brightest in the night sky with a visual apparent magnitude of 0.34...
) release on 2007 August 22 - Humu (Altair) release on 2008 February 8.
- Lehuakona (AntaresAntaresAntares is a red supergiant star in the Milky Way galaxy and the sixteenth brightest star in the nighttime sky . Along with Aldebaran, Spica, and Regulus it is one of the four brightest stars near the ecliptic...
) release on 2008 November 12. - Nanahope (PolluxPolluxPollux may refer to:Astronomy*Pollux , *Pollux, a crater on the Saturnian moon EpimetheusFictional characters*Pollux Black, a pureblood wizard, grandfather of Sirius Black in the Harry Potter universeGames...
) release on 2009 July 27. - Hawaiki (DenebDenebDeneb is the brightest star in the constellation Cygnus and one of the vertices of the Summer Triangle. It is the 19th brightest star in the night sky, with an apparent magnitude of 1.25. A blue-white supergiant, Deneb is also one of the most luminous nearby stars...
) release on 2010 January 20. - Namaka (Lambda ScorpiiLambda ScorpiiLambda Scorpii is the second brightest star system in the constellation Scorpius, and one of the brightest stars in the nighttime sky. It has the Bayer designation λ despite being the second brightest in its constellation...
) release on 2011 February 8.