It is a difficult task to summarise the results of twenty years-long research activity of a multidiscipine scientific institution like the Space Research Centre. Since the bridge spanning the different fields of research carried out by the institute is space technology, it seems appropriate to recollect some statistical data on the scientific instruments put in space by SRC over the past twenty years.
During 1977 – 1997 the SRC staff developed, constructed and prepared for launch 39 instruments, including 19 for sub-orbital rocket flights and 20 for satellite missions.
The first experiments of the institute were launched chiefly on Soviet VERTICAL rockets within the framework of INTERCOSMOS cooperative programme, but the last rocket experiment was launched in 1992 onboard a NASA Terrier Black Brent rocket.
The first satellite experiment involved two instruments developed by SRC, launched in 1986 onboard IONOSONDE mission (Cosmos-1809). Apart from the INTERCOSMOS satellites the instruments developed by SRC were used onboard the space probes Phobos 1 and 2, Vega, and Mars-96 and were deployed on the Mir space station. Finally, a thermal sensor developed by SRC is currently onboard the Huygens probe underway to Saturn and its satellite Titan as part of the international NASA/ESA planetary mission CASSINI.
Apart from the hardware launched into space the institute constructed many unique ground-based appliances, like the KOS ionosonde, laser range metre, microwave soil dampness tester, and a spectrometer to measure visual reflective characteristics of natural objects, used to carry out experiments by SRC and other institutions.
Results from all space experiments performed by SRC were discussed in many scientific publications in international and national journals and conference proceedings.
During 1992 – 1997, i.e. during the time period covered by Annual Reports of the institute that list publications and talks at international conferences by SRC scientists, they published 488 articles in the following journals:
Advances in Space Research 58 Annales Geophysicae 13 Astronomy & Astrophysics 28 Icarus 7 Journal of Geophysical Research 7 Planetary and Space Science 13 Space Science Reviews 7 National journals (including, among others, Acta Astronomica, Acta Geophysica Polonica, Artificial Satellites) 75 Other (e.g. Astrophysical Journal, Geophysical Research Letters, Kosmicheskie Issledovanya, Radio Science, Review of Scientific Instruments) 114 Conference Proceedings 161 How did the twenty years of research activity of Space Research Centre contribute to the global knowledge of the Earth and its space environment? Beginning from the everyday applications let us mention two issues. The first one is connecting Poland to the European fundamental geodetic reference system EUREF (European Reference Frame). Using a global satellite positioning system GPS, for the first time in Poland a unified geodetic network was constructed and connected to the European network.
The Polish network has 358 nodes with coordinates measured with centimetre accuracy. It facilitates practical applications in a common reference system with the European Community countries as well as scientific research.
Another issue is development of a model of the ionosphere above Europe. The model is used by SRC to provide state of the art heliogeophysical prediction service for the national telecommunications service and the International Space Environment Service (ISES).
A look at the Earth as planet draws attention to further two aspects of SRC activity. On one hand, continuous activity of the institute in a framework of international measurement networks in geodynamics and laser observations of satellites gave access to data, analysis of which brought discovery of short-term oscillations of the Earth pole and perturbations of its rotation and their correlation with some geophysical phenomena. On the other hand, numerous rocket and satellite experiments enabled getting a strong grasp on the electromagnetic environment of the Earth and the discovery its antropogenic conditioning.
SRC has specialised in investigation of space plasmas. Experiments on interaction of modulated electron beams with plasma gave information on excitation and propagation of plasma waves. They brought contribution to the development of plasma physics by the use of space as a unique plasma laboratory and enhanced knowledge on the upper atmosphere. Studies of scintillation of the electromagnetic waves emitted by Earth’s satellites enabled developing of a picture of turbulence in the ionosphere which is an important factor in the model of this region and has to be taken into account in predictions of electromagnetic waves propagation conditions. The existence of thin current sheets during magnetic storms in the polar regions of terrestrial magnetosphere was predicted. A new plasma population in the inner magnetosphere, called in the literature a warm shell of the plasma sheet, was discovered.
Experimental and theoretical studies of the solar corona, where the plasma temperature is millions of kelvins hot, and in particular development of the methodology and instruments to collect and analyse the x-ray spectra of solar flares, made possible to determine the chemical composition of solar plasma and to better understand the processes of energy deposits in the solar corona.
Among the most interesting results of studies of interaction of the solar wind plasma with the Local Interstellar Medium, conducted with particular stress on the analysis of the shape of the heliopause and physical processes going on in its vicinity, it is worth to point out a hypothesis on the source of interplanetary radio emission at 2 – 3 kHz observed by Voyager. Apart from that the first realistic model of density, velocity and temperature of interstellar hydrogen within the interplanetary space was developed, including non-stationary effects of solar radiation pressure and ionisation rate.
SRC took part in the experiment of the first in-situ detection of neutral interstellar helium atoms on Ulysses and in the interpretation of helium pickup ion data from AMPTE/IRM, where the existence of neutral helium cone, predicted by theoretical studies conducted in SRC, was experimentally confirmed.
Theoretical models of planetary magnetotails were developed, which brought predictions on the shapes of these plasma formations; the models for Earth and Jupiter were confirmed experimentally by the ISEE 3 and Voyager, respectively.
The investigation of the plasma environment of Comet Halley during Vega mission brought discovery of morphology of plasma waves around the nucleus.
An interesting, though unexpected, development during the mission was the use of a double probe antenna as detector of dust particles. The contribution of SRC to investigations of subtle effects in cometary motion has also to be pointed out.
For the first time a cometary nucleus and its activity were observed during the Halley campaign; SRC used this information to develop a model of non -gravitational forces affecting the cometary motion and to include it in orbital studies.
Among many periodic comets whose models of motion were constructed, included is Comet Wirtanen that will be thoroughly studied by the future ESA milestone mission ROSETTA. SRC is participating in several experiments on this mission.
At the end the participation of the institute in a large-scale, multi-task and technologically sophisticated mission CASSINI to Saturn and its satellite Titan should be pointed out again. The instrument developed by SRC, being part of the mission, was mentioned at the beginning of this Report, so here we stress that the invitation for the institute to participate in the mission was possible thank to the twenty years experience and successful research/development activity of the Polish national space research facility.
