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The main goals of the Chibis-M mission are the testing of a new micro-satellite technology, the study of new physical processes related to lightning activity and the verification of possible monitoring techniques of Space Weather phenomena. In frames of the Chibis-M mission an electromagnetic wave complex MWC is installed on board of the satellite composed of electromagnetic sensors and SAS3 measuring unit. The obtained data show that the scientific instrumentation operates properly and produces interesting information. Here we present the first results of the first year of operation of the MWC in the ELF–VLF bands in different operation modes. An important conclusion is that basing on the experience of the first year it is possible to realize an effective and reliable Space Weather monitoring system using micro-satellites and simultaneously operating ground support equipments.  相似文献   
2.
Information about the amount and spatial structure of atmospheric water vapor is essential in understanding meteorology and the Earth environment. Space-borne remote sensing offers a relatively inexpensive method to estimate atmospheric water vapor in the form of integrated water vapor (IWV). The research activity reported in the present paper is based on the data acquired by the HRPT/MODIS (High Resolution Picture Transmission, MODerate resolution Imaging Spectroradiometer) receiving station established in Budapest (Hungary) by the Space Research Group of the Eötvös Loránd University. Integrated water vapor is estimated by the remotely sensed data of the MODIS instrument with different methods and also by the operational numerical weather prediction model of the European Centre for Medium-Range Weather Forecasts (ECMWF). Radiosonde data are used to evaluate the accuracy of the different IWV fields though it has been pointed out that the in situ data also suffers from uncertainties. It was found that both the MODIS and the ECMWF based fields are of good accuracy. The satellite data represent finer scale spatial structures while the ECMWF data have a relatively poor spatial resolution. The high quality IWV fields have proved to be useful for radiative transfer studies such as the atmospheric correction of other satellite data from times different than the overpass times of satellites Terra/Aqua and the forecast times of the model data. For this purpose the temporal variability of IWV is scrutinized both using ECMWF and MODIS data. Taking advantage of Terra and Aqua overpasses, the mean rate of change of IWV estimated by the near infrared method was found to be 0.47 ± 0.45 kg m−2 h−1, while it was 0.13 ± 0.65 kg m−2 h−1 based on the infrared method. The numerical weather prediction model’s analysis data estimated −0.01 ± 0.13 kg m−2 h−1 for the mean growth rate, while using forecast data it was 0.24 ± 0.18 kg m−2 h−1. MODIS data should be used when available for the estimation of the IWV in other studies. If no satellite data are available, or available data are only from one overpass, ECMWF based IWV can be used. In this case the analysis fields (or the satellite field) should be used for temporal extrapolation but the rate of change should be calculated from the forecast data due to its higher temporal resolution.  相似文献   
3.
In a previous paper, the author described a hypothetical development path of technical civilisations which has the following stages: planet dwellers, asteroid dwellers, interstellar travellers, interstellar space dwellers. In this paper, several scenarios are described which may cause the rise of an asteroid-based technical civilisation. Before such a transition may take place, certain space technologies must be developed fully (now these exist only in very preliminary forms): closed-cycle biological life support systems, space manufacturing systems, electrical propulsion systems. After mastering these technologies, certain events may provide the necessary financial means and social impetus for the foundation of the first asteroid-based colonies. In the first scenario, a rich minority group becomes persecuted and they decide to leave the Earth. In the second scenario, a "cold war"-like situation exists and the leaders of the superpowers order the creation of asteroid-based colonies to show off their empires' technological (and financial) grandiosity. In the third scenario, the basic situation is similar to the second one, but in this case the asteroids are not just occupied by the colonists. With several decades of hard work, an asteroid can be turned into a kinetic energy weapon which can provide the same (or greater) threat as the nuclear arsenal of a present superpower. In the fourth scenario, some military asteroids are moved to Earth-centred orbits and utilised as "solar power satellites" (SPS). This would be a quite economical solution because a "military asteroid" already contains most of the important components of an SPS (large solar collector arrays, power distribution devices, orbit modifying rocket engine), one should add only a large microwave transmitter.  相似文献   
4.
The era of modern space research and applications began with the 1945–46 Moon-radar experiments and with the successful launch of the first artificial satellite, Sputnik-1. Hungary and Hungarian engineers/researchers were present at the birth of this new and important discipline. As a consequence of the Second World War Hungary became part of the Soviet bloc and, for the first 30 years of the Space Age, Hungarian space activity was carried out mainly within Intercosmos; however, some highlights were produced. After the collapse of the communist dictatorship Hungarian space activity was successfully rebuilt and the past 20 years have seen the beginning of the integration of Hungarian space activity into ESA and EU space policy. Hungarian society’s attitude to the country’s space activity is complex, as is that of its decision makers. This largely results from the simplified picture of global space activity and Hungarian participation therein in people’s minds and from the ignorance of the country’s decision makers. While this is basically a global problem, it has a special Hungarian aspect in the view that a small country has no real role in the world, in the EU, in ESA or in global space activity. We have a task: to change this mind-set.  相似文献   
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