The Liège space adventure

By Théo Pirard

The University of Liège has always been renowned for its astronomy and astrophysics research, particularly since the construction of the Cointe observatory in 1883. The conquest of space symbolised by the launch of the first artificial satellite gave its activities a new dimension. On the one hand the research carried out by astronomers and astrophysicians benefited from data collected from beyond the Earth’s atmosphere, and on the other hand a large aerospace sector would now develop at the technological and industrial levels.

Three witnesses at the university have recounted this double characteristic of the Liège space odyssey: the astrophysicist Jean-Pierre Swings (the AGO (Astrophysics/Geophysics/Oceanography) department, the engineer-physicist André Monfils (founder and first director of the Space Work Group, which became IAL Space and then the Liège Space Centre), and the engineer-physicist and astrophysicist Claude Jamar (director of the Liège Space Centre, and a driving force behind WSL/Wallonia Space Logistics).

Spoutnik : les témoins

 

Fifty years ago universities and scientific institutions carried out research in astronomy, astrophysics and geophysics. As for the engineers in their design offices, they dreamed of astronautics and produced plans for space stations and lunar expeditions. Going into space was above all an idea that figured in the imaginations of novelists, cartoonists and science fiction scriptwriters. Nonetheless, this was achieved. Researchers the world over had decided to organise an International Geophysical Year, from 1st July 1957 to 31st December 1958. Both the United States and the Soviet Union (of which present day Russia and Ukraine were a part of) had announced their intention to launch satellites to make observations and collect data from beyond the Earth’s atmosphere. Europe for its part remained attentive to what plots were being cooked up for the conquest of the dimension of space in the West and the East.

Beyond the atmosphere

At the University of Liège the Astrophysics Institute, which then had its rooms, workshops and telescopes at the Cointe Observatory, was very interested in experiments carried out through rocket probes and on board satellites. It was headed by the astrophysicist Polydore ‘Pol’ Swings (1906-1983), known internationally for his spectroscopic and optical research. His son Jean-Pierre, then aged 14 and who was to become a Doctor of Astrophysics, remembers this morning of 5th October when the radio announced that Sputnik had been placed in orbit. News of this ‘first’ sparked off enthusiasm. The launch of a satellite constituted a great event for the scientific community of the International Geophysical Year. For Pol Swings access to space opened a new window onto the celestial vault because it enabled spectroscopy in the ultraviolet and infrared ranges. It was imperative to go beyond the atmosphere to carry out, in excellent conditions, observations of spectral lines which do not penetrate the layers of the atmosphere.

The protective cocoon of our atmosphere constitutes an impediment for ultraviolet and infrared observations. To overcome it instruments have to be placed at high altitudes. Thus in 1950 Professor Marcel Migeotte (1912-1992) installed a first spectrograph at the Jungfraujoch scientific station, at an altitude of 3,751m, in the Berne Alps. On studying the Sun from this peak, the Liège researchers highlighted the interactions between the terrestrial world and the environment of space. Realising that our atmosphere is changed by pollution they were among the first to draw attention to climate change. Today they continue to survey chemical reactions in the atmosphere for the global community.

Jungfraujoch EN

 

At the end of the 1950s, at a time when the Soviet Union and the United States were launching their first satellites, the University astrophysicists made clear their interest and stamped their feet with impatience to carry out research in space. As the director of the Astrophysics Institute, Professor Swings took some audacious initiatives. He made himself heard attentively within the European scientific environment. Through the art of subtle lobbying he made co-operation between teams and researchers successful. His priority, in the 1950s, was to bring together national skills in astronomy and astrophysics within international organisms. He thus contributed to the creation of COSPAR (Committee on Space Research) in 1958, to organising ESO (European Southern Observatory) in 1962 and the setting up in 1964 of ESRO (European Space Research Organisation), which in 1975 gave birth to ESA (the European Space Agency). He made sure that the University of Liège, through its participation in a European space science programme, had a key role in Europe’s space odyssey.

Aware of the fact that space technology would revolutionise discoveries in astrophysics, Professor Swings sent André Monfils, at that time his assistant, to distant ultraviolet specialists in Ottawa (1959) and then in Harvard (1960). On his return, he committed the Astrophysics Institute’s research to the ultraviolet (UV) emissions of the Northern lights, or aurora polaris. One of its tasks was to carry out experiments with rocket probes fired from Sardinia (de Salto di Quirra base) with the aim of causing artificial comets. One of these rockets, a reminder of the epic beginnings of the ‘Cité Ardente’ (as Liège is known locally) in the domain of space is exhibited in the entrance hall of the Liège Space Centre, located at the Sart Tilman campus.

 

A fighter’s tricky journey

In 1962, Professor Monfils, set up, at the heart of the Astrophysics Institute, a Space working group (Optics and space physics section) which took the name IAL Space. This team, where Claude Jamar was to be found as project chief, conceived, designed and built the instrument – the S2/S68 ultraviolet telescope – of the first European astronomy satellite in space (ESRO Programme) which used three axis stabilisation. The TD-1 observatory, placed around the Earth on 12th March 1972 by an American Thor-Delta rocket, worked for two years in establishing the first ultraviolet sky map which included the characteristic features of around 30,000 hot stars.

The success of the TD-1 gave the Cointe IAL Space department honour and prestige. The optical instrument S2/S68 – a 0.27m telescope combined with a spectrometer – was tested and calibrated at the Liège Astrophysics Institute. To do this, a space environment simulator was built there. If the overall instrument was built by a French master-builder, the tank, with a diameter of 2m and a length of 5m and in which was created a vacuum and thermal variations, was the work of the Meuse Workshops in Liège. This simulator, baptized FOCAL 2 (Facility for Optical Calibration at Liège) became the nub of an infrastructure for testing optical systems designed for satellites, space observatories and interplanetary probes. Claude Jamar and his team of engineers, researchers and technicians on this occasion demonstrated their ability to bring to fruition the development of complex equipment for missions within space. The ESA, created in 1975, could entrust them with optical calibration tests for the meteorological satellite Meteosat’s radiometer and the Halley Multicolour Camera (HMC) for the comet probe Grotto.

The aftermath of TD-1 was nevertheless a difficult period. In the confines of the Cointe Observatory IAL Space was undergoing a crisis period. Space technology, particularly costly, in effect demands large subsidies. The solution was found at European level in 1975 with the signing of a memorandum of understanding between the University and ESA (the European Space Agency).

 

Heading for the Sart Tilman

The integration of 1AL Space within a European network with the means to carry out space tests saved Professor Monfils team and preserved the technological skills the university can be proud of. IAL Space has gained recognition as a centre of excellence in Europe for the qualification and calibration of opto-electronic instruments which must operate in the extreme conditions found in space. The quality of its performances for the ESA and the European space industry was confirmed for the series of tests for the Metoesat programme and the Grotto space mission. The ESA satellites nevertheless became more ambitious and took up more room, and the FOCAL 2 simulator became too cramped and its performances too limited. IAL Space, in order to test the optics of the Hippocras astometrics satellite, designed FOCAL 5 with a diameter of 5m and a length of 6.6m. To receive this new ESA financed simulation tool IAL Space had to grow and in 1984 it was obliged to relocate to the Sart Tilman Science Park.

Halley's comet nucleus



A building with an area of some 4,000m² was built with the support of the Wallonia Region, around a clean room which shelters three simulation tanks. The Liège AMOS company (Advanced Mechanical and Optical Systems), a subsidiary of the Meuse Workshops (Ateliers de la Meuse), was given the responsibility of supplying FOCAL 5 and building the new infrastructure. The first equipment to be tested there – under the supervision of Claude Jamar and Antonio Cucchiaro – was without doubt the most prestigious in European space programmes: the camera for the Giotto probe which took the historical pictures of the core of Halley’s Comet in March 1986!

An international benchmark

There then came a whole series of tests in the FOCAL simulators of more and more complex and delicate opto-electronic equipment designed for space missions. The Sart Tilman site became a high technology laboratory for testing – in severe conditions and at extremely low temperatures – and calibrating infrared observations. Calibration tests on a multitude of telescopes which functioned extremely well in the environment of space have been carried out there. IAL Space has contributed to the successful European Hipparcos astrometrics satellite and the ISO infrared astronomy satellite. It developed the detection system on the European instrument of the famous NASA Hubble Space Telescope.

IAL Space became an international benchmark for space optics design, metrology and calibration. A team of engineers – around Pierre Rochus, and then Jean-Marc Defise – relaunched the activity that marked the beginnings of IAL Space, the design and development of original and innovative satellite instruments, for the ESA and NASA. In 1988, with the Wallonia Region providing its impetus, IAL Space witnessed the birth, through its proximity and through members of its personnel, of the Spacebel twins, two space system commercial businesses: Spacebel Instrumentation, which went into liquidation in 1997, and Spacebel Informatique, which has become a European specialist of intelligent systems for space missions.

‘Spatiopôle’ makes the headlines

In 1991, the founder and director of IAL space took his retirement: Professor Monfils was replaced by Claude Jamar, one of his students and researchers, who was at his side for the launch of the Space Department of the Astrophysics Institute. From April 1992 onwards IAL Space took the name of the Liège Space Centre (CSL): it stated its intention to grow as a centre of excellence of new technologies in the European context and at the service of the region. Professor Jamar’s objective was to constitute, within the CSL orbit, a Walloon ‘space centre of excellence (‘Spatiopôle’) which would unite and integrate on the same site university skills in astrophysics and geophysics, in aerospace engineering, and in optics and computing, so that it could provide the university with an influential role within the perspective of the Bologna Reforms. It means furthermore making good use of scientific potential and technological expertise to stimulate and facilitate the hatching of spin-offs or high technology shoots in Wallonia. In 2001 Wallonia Space Logistics (WSL) took shape with the support of the Walloon government to become the first European incubator of products and services with high value added which have derived from research and development in space technologies and engineering sciences.

The CSL is at present working on around 50 projects, with around a 100 collaborators, and with a turnover of around 15 million Euros. Within its orbit and with it providing the momentum, two private companies took shape in the 1980s thanks to initiatives in space technology: AMOS, to supply test material and opto-mechanical equipment (including ground based telescopes), and Spacebel, which develops computer programmes adapted for operations in orbit. They were joined by the Samtech company and its subsidiary, Gdtech, which are active in modelling complex structures with the SAMCEF software (Système pour l’Analyse des Milieux Continus par Eléments Finis: Systems Analysis of Continuous Environments by finite elements). This method is the result of research work carried out by LTAS (Laboratoire de Techniques Aéronautiques et Spatiales: Aeronautical and Space Technology Laboratory) of the Faculty of Applied Sciences. Finally, there is the WSL incubator, whose business park is expanding: this ‘hatcher’ is aiding around 30 young Small and Medium Sized Businesses in bringing technological innovations to the market. Among them LASEA (1999), Optrion (2001), KeyObs (2001), WalOpt (2004), and Athol (2006) are making use of fallout from CSL activity.

Spoutnik Planck EN

On the point of retiring – from 1st October, Jean-Marc Defise will succeed him at the head of the CSL – Claude Jamar is delighted with the ‘virtual gathering’ which is in the process of operating between the University of Liège’s space related activities. He insists on the importance of having academic connections between the CSL and the departments with space themes in the Faculty of Sciences (Astrophysics, Geophysics, Oceanography) and the Applied Sciences (Aerospace and Engineering). Already, the engineer-physicist Serge Havraken, responsible for the CSL optic instrumentation, is a lecturer in the Physics Department (Hololab). It is anticipated that this synergy within the University will grow with the birth of two new Masters academic programmes – space sciences and aerospace engineering – which will set to work at the beginning of this academic year.

Observations of the Sun’s ‘weather’

Since the beginning of the space era in 1957, IAL Space/CSL has been involved in around twenty satellites – European, American and French – through opto-electronic equipment it has designed and/or calibrated. It is not at all surprising that half of the observatories that the ESA has in service or in preparation have included Liège participation. Today, thanks to the CSL the scientific community has an unparalleled daily view of the choppy surface of the Sun. Liège know-how is found on board the American-European SOHO satellite (Solar & Heliospheric Observatory) in the form of a telescope which works in extreme ultraviolet ranges (EIT, Extreme ultraviolet Imaging Telescope): launched in December 1995, it has been placed 1.5 million kilometres from us and is permanently pointed towards ours star. The EIT images reveal, practically in real time, the capricious activity of the Sun. The spectacular images can be found at http://sohowww.nascom.nasa.gov/.

At the same time, since the end of last year, a duo of NASA space observatories is making the SOHO imaging complete by looking at the solar disc from different angles. This STEREO mission (Solar Terrestrial Relations Observatory), which was launched in October 2006, provides a new field of vision for astrophysicists who study the Sun, in particular the unpredictable phenomenon of solar flares, in recording simultaneous observations from three satellites orbiting the Sun. These 3D observations contribute to a new discipline, ‘space weather’, whose goal is to understand and predict solar flares, to determine their affects on the Earth and on human activity (aurora borealis, electromagnetic perturbations of satellites and electricity networks, navigation and telephone systems). Did you know that the Naval Research Laboratory (NRL) drew on CSL expertise to develop the heliospheric imager’s double optical system and the ensemble of the occluding masks which the principal instruments of each STEREO satellite are equipped with (read The sun in STEREO)? The next ESA made-in-Belgium satellite, PROBA-2, will be a micro-observatory of the Sun: it should be placed in orbit in Autumn 2008 after being equipped with a radiometer and an ultraviolet telescope which will see the light of day in the CSL.

On the hunt for black holes and exoplanets…

In 1995 the Liège Space Centre doubled its infrastructure in order to equip itself with the giant FOCAL X simulator that the ESA needed to test the delicate mirrors of its XMM-Newton satellite. This astrophysical observatory, which has been circulating the Earth since December 1999, uses its mirrors to collect X-rays from the universe which betray the presence of very violent phenomena such as black holes, neutron stars and processes at work at the heart and at the origin of galaxies. The data gained is used by the Liège Astrophysics and Geophysics Institute (IAGL). The ESA has also given the Liège University centre the responsibility of testing the Herschel and Planck telescopes, its next observatories of the universe, and to calibrate their performances. The FOCAL X simulator was adapted, between July 2002 and September 2003, and became FOCAL XXL in order to test its infrared instruments at temperatures close to absolute zero (that is to say at minus 273.15° Celsius, or 0 Kelvin). A new wing had to be constructed at the Liège Space Centre in order to accommodate the teams responsible for the tests.

Spoutnik : Focal XXL EN


In the meantime the Cointe Observatory, with its cupola sheltering its telescopes, has had its time. In 2002 the Liège Astrophysics and Geophysics Institute moved to a new building attached to the Physics Institute on the Sart Tilman campus. At the heart of the AGO (Astrophysics, Geophysics and Oceanography) university department, it constitutes a centre of worldwide renown for the surveying of the global changes of air and water cycles, the study of the aurora phenomena as far away as Jupiter and Saturn (using Hubble Space Telescope images), and for research into the universe’s massive structures and high energies. The IAGL researchers often call on the services of the ne plus ultra of observatories, such as the ESO (European Southern Observatory) at the summits of the Chilean mountains. They also have a presence at the Cerro Paranal based VLT (Very Large Telescope), which allows for the very detailed study in three dimensions of the sky’s phenomena. The astrophysicist Jean-Pierre Swings insists on the essential and enriching complementarity between earthbound instruments and systems located in space.

Within the framework of the ESA’s (European Space Agency) scientific programme, the IAGL is a specialist in using the X ray and gamma ray data obtained by the currently orbiting space observatories INTEGRAL and XMM-Newton. It contributes to the mission of the French satellite COROT (star interior convection and rotation): in space since December 2007, its telescope, of which certain optic-mechanical elements were supplied and tested by the Liège Space Centre is in the process of observing some 100,000 stars in order to detect the presence of planets circling around them, or exoplanets (see our article Voyage to the Centre of the Stars). It also co-operates with the Liège Space Centre and the business company AMOS in setting up new detectors for the space observatories of the next decade and in an international project to construct terrestrial liquid mirror telescopes in Chile and India. This spectrum of ULg space activities shows that Liège has been well capable of taking on the heritage of Sputnik.

 

The Liège space adventure : useful readings