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Raport Gotowy 2012 SPACE RESEARCH CENTRE POLISH ACADEMY OF SCIENCES ANNUAL REPORT 2012 WARSAW SPACE RESEARCH CENTRE Polish Academy of Sciences Bartycka 18A, 00-716 Warsaw, Poland Phone: (48-22) 49 66 200 Fax: (48-22) 840 31 31 e-mail: [email protected] SUMMARY 2012 In November 2012 Poland became the 20th member of European Space Agency, which was a very significant event for the whole Polish space sector. SRC experts were strongly involved in consulting the strategic document about development of space activity in Poland prepared by the Ministry of Economy. The objectives to be pursued in the next years are: (i) establishing the national space program, (ii) establishing new discipline in higher education – space and satellite engineering, (iii) developing strong space industry and (iv) supporting the government in strengthening the Poland's role in shaping the EU and ESA space policy. The main achievements of Space Research Centre PAS in 2012 comprise: • The best currently available maps of energetic neutral atoms of interstellar origin, corre- cted for heliospheric extinction, have been developed in collaboration between the American and Polish science teams of the NASA Interstellar Boundary Explorer Mission (IBEX). These maps serve as a basis for further studies of the heliosphere, for instance the new IBEX measurement of the velocity vector of interstellar gas inflow on the heliosphere were interpreted by the IBEX team as an indication that the range of the disturbance of the Local Cloud gas by the heliosphere is much larger than previously thought. Consequently, the structure of the bow region of the heliospheric interface much more complex (the flow is submagnetosonic, i.e. without a bow shock) than previously considered. • The Herschel Solar System Observations (HssO) Consortium that includes researchers from SRC PAS investigated the isotopic composition of comets, the nature of cometary activity and the thermodynamics of cometary comae. A new measurement of the deuterium-to- hydrogen ratio in the water of comet C/2009 P1 (Garradd) suggests that the deuterium enri- chment in water of Oort-cloud comets is not as high as previously thought, at least for a fraction of the population. This confirms the earlier findings from the data taken by Herschel Space Observatory that revealed ocean-like ratio in Jupiter-Family comet 103P/Hartley 2. A compa- rison of existing, mostly ground-based, and new HIFI measurements of D/H in comets indi- cates isotopic diversity in the comet population. The D/H ratio in cometary water is an important indicator of the conditions under which icy planetesimals formed in the Solar System and can provide clues to the contribution of comets to the delivery of water to Earth. • One of the future ESA cornerstone missions, Solar Orbiter, is in an advanced phase of payload development. SRC research and engineering group participates in the STIX experiment within a multi-national European Consortium led by Swiss Windish University of Applied Sciences. For this imaging spectrometer of thermal and non-thermal solar X-ray emission from 4 to 150 keV SRC provides the on-board computer based on sophisticated FPGA technology as well as the system of ground-control, software and testing. Very important for the instrument success is a dedicated hardware-software system of detector simulators, currently under development at the Solar Physics Division in Wroclaw, that will allow to create all signal and data streams for numerous X-ray model sources. • In the frame of a joint Austrian, Canadian and Polish scientific project BRITE (BRIght Target Exporer) each country will provide 2 spacecraft that will conduct observations of bright, massive stars of our galaxy, through photometric measurements, measuring low frequency oscillations and star temperatures. SRC will deliver 2 spacecraft, each of a mass of 7 kg. The first satellite, LEM, is ready for launch. The second satellite, HEWELIUSZ is undergoing functional tests. The scientific team comprises researchers from Copernicus Astronomical Center PAS and University of Wrocław. 3 • A novel method of time and frequency transfer using optical fibers has been developed by a team comprising researches from SRC and AGH University of Science and Technology. The precise method of auto-calibration that was tested on a 420 km long glass fibre link between Borowiec Observatory (AOS) and Central Office of Measures (GUM) in Warsaw and showed the stability of frequency comparisons at a level of 1x10-18. The error of comparisons of atomic clocks at AOS and GUM does not exceed 10 ps, which is currently the best result of long-distance time transfer in the world and proves the quality of the developed method. The link was supported by PCSS Pionier and Orange Telecom. 4 SPACE PROJECTS Bepi Colombo – ESA mission to Mercury BepiColombo is Europe's first mission to Mercury. It consists of two orbiters, one for planetary investigation and one for magnetospheric studies. They will reach Mercury in 2020 after a six- year journey towards the inner Solar System to make the most extensive and detailed study of the planet ever performed. The 'Mercury Planetary Orbiter' (MPO), under ESA's responsibility, will study the surface and the internal composition of the planet at different wavelengths and with different techniques. The Mercury Magnetospheric Orbiter (MMO), under the responsibility of the Japan Aerospace Exploration Agency (ISAS/JAXA), will study the magneto-sphere, that is the region of space around the planet that is dominated by its magnetic field. Space Research Centre is involved in the The MPOI as one of the spectrometer modules is MPO-MERTIS and ISA experimensts. situated in front of MERTIS to orient the optical The experiment MERTIS (MErcury Radio- entrance of the instrument to 4 different targets meter and Thermal Infrared Sectro-meter) is lead sequentially. These targets are the Mercury surface by German Space Institute from Berlin. The and deep space as well as two black body of 300 MERTIS is dedicated to global mineralogical and 700 K. Besides strong needs for miniaturiza- mapping and measurements of surface tempera- tion environmental conditions are key for design tures and thermal inertia in the spectral range of details: operational temperature range –30°C to 7-14 µm. +70°C, random vibration loads around 40g rms SRC is responsible for the part of the and high level of radiation. The required perfor- spectrometer – Pointing Unit (acronym MPOI). mance is characterized with a pointing accuracy 0.8 arc min for the main targets and a poin- ting mirror flatness of better than 0.4 µm for sufficient wave front quality. The following tasks were realized in 2012: 1. Redesign of Flight Model to fulfill the radiation requirements for magnetic sensors; 2. Qualification test at dummy Flight Model; 3. Full acceptance tests of Flight Model; 4. Assembling and tests of Spare Flight Model. (M. Rataj) Fig. 1. FM of the MPOI. program packages written in Matlab. Calibration In 2012, work on the calibration of the system of the instruments is a very important issue in the of accelometres designed for a probe to Mercury implementation of the ISA, an experiment which had been completed as part of the BepiColombo is part of the BepiColombo mission. The work- /ISA project, which has been set up in coopera- in-progress product is an ISA simulator operating tion with a group lead by professor V. Iafolla of within the standards developed by ESA interpla- the Institute of Astrophysics in Rome. (ISA= netary missions. The Polish team worked in the Italian Spring Accelerometer). The main result of frame of the cooperation agreement with the Ita- this project is a practical solution to performance lian team, J. B. Zieliński worked as a Co-Investi- issues in Italian accelerometer calibration (PI – gator. It is decided to continue this cooperation Valerio Iafolla) on the BepiColombo space mis- under the agreement with ESA. This opens up the sion to Mercury, as well as preparing necessary possibility of access to the data collected during tools for procedures during a flight to the planet, the mission, once the interplanetary probe com- or a flight in orbit, in the form of algorithms and pletes its cycle. 5 In addition to the main body of work on the measuring the speed of gravity signal could be problem of calibration, it was also necessary to possible with the use of advanced gradiometric take up complementary work. The teams technology. This would be of great importance to researched and published a paper on earth tides the study of fundamental physics. It must be kept and published work on ground accelerometry. It in mind, however, that this result is not confirmed seems that an interesting result of this research by the scientific community of theoretical physics. was a development of an idea concerning the use The results have been presented in five of relativistic theory of gravity to determine the papers, of which two were published, two submit- speed of gravitational interaction (gravitational ted for publication, and one is an internal report. signal). Whilst studying issues related to some of In addition, many of the results were presented at the objectives of the BC mission regarding the the very prestigious COSPAR conferences in theory of relativity, it was noted that the rotation 2008, 2010, and 2012, both in the form of posters of a planet must generate anomalous twist of the and oral presentations, as well as at national and gravity field of the planet. Very subtle gravita- international lower-level meetings. tional effects can be measured with highly sensi- (J. Zieliński, M. Kalarus) tive gradiometres. Our calculations indicate that ASIM ASIM - The Atmosphere-Space Interactions Monitor (ASIM) aboard ISS is proposed for the study of high-altitude optical emission from the stratosphere and mesosphere related to thunderstorms.
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