Non-destructive sampling of a comet

The boundary conditions for a non-destructive sample acquisition system are outlined and the development of a new robotic sampling system suited for use on a cometary surface is briefly discussed. Additionally we present some new results on strength and deformation behaviour of synthetic cometary analogue material.     

The United Nations Programme on Space Applications: Status and direction for 2010

The United Nations Programme on Space Applications was established in 1971 to assist countries in making full use of the benefits of space technology and its applications for social and economic development. Since its inception the programme has organized numerous training courses, workshops, seminars and conferences and provided funding support for more than 10?000 experts, mainly from developing countries, to participate in those activities. The programme has continuously evolved over four decades, taking into account the latest developments in the field of space activities, to best serve the capacity-building needs of countries and to help ensure that space-based solutions contribute to improving life on Earth. This report describes the status and direction of the UN Programme on Space Applications as recommended for approval by the UN’s Committee on the Peaceful Uses of Outer Space (UNCOPUOS) Scientific and Technical Subcommittee at its 47th session held in Vienna in February 2010.     

Recent results from COMPTEL

The COMPTEL telescope aboard the Compton Gamma Ray Observatory has put MeV -rays into the midst of astronomy. Among recent highlights are the discovery of intense MeV emission from blazar-type active galactic nuclei, the surprising non-detection of any Seyfert galaxy at MeV energies, the first image of the Milky Way in the light of the²⁶Al line at 1.809 MeV (possibly including a detection of the Vela supernova remnant), the discovery of 3–7 MeV emission from the Orion complex, which can be identified with nuclear interaction lines of¹²C and¹⁶O at 4.44 and 6.13 MeV, the detection of the⁴⁴Ti line at 1.15 MeV from the supernova remnant Cas A, and the first results on the spectrum and propagation of low-energy (1–100 MeV) cosmic-ray electrons.also Leiden Observatory     

The Burst Alert Telescope (BAT) on the SWIFT Midex Mission

he burst alert telescope (BAT) is one of three instruments on the Swift MIDEX spacecraft to study gamma-ray bursts (GRBs). The BAT first detects the GRB and localizes the burst direction to an accuracy of 1–4 arcmin within 20 s after the start of the event. The GRB trigger initiates an autonomous spacecraft slew to point the two narrow field-of-view (FOV) instruments at the burst location within 20–70 s so to make follow-up X-ray and optical observations. The BAT is a wide-FOV, coded-aperture instrument with a CdZnTe detector plane. The detector plane is composed of 32,768 pieces of CdZnTe (4×4×2 mm), and the coded-aperture mask is composed of ∼52,000 pieces of lead (5×5×1 mm) with a 1-m separation between mask and detector plane. The BAT operates over the 15–150 keV energy range with ∼7 keV resolution, a sensitivity of ∼10⁻⁸ erg s⁻¹ cm⁻², and a 1.4 sr (half-coded) FOV. We expect to detect > 100 GRBs/year for a 2-year mission. The BAT also performs an all-sky hard X-ray survey with a sensitivity of ∼2 m Crab (systematic limit) and it serves as a hard X-ray transient monitor.     

Distribution and stable isotopic composition of amino acids from fungal peptaibiotics: assessing the potential for meteoritic contamination

The presence of nonprotein α-dialkyl-amino acids such as α-aminoisobutyric acid (α-AIB) and isovaline (Iva), which are considered to be relatively rare in the terrestrial biosphere, has long been used as an indication of the indigeneity of meteoritic amino acids. However, recent work showing the presence of α-AIB and Iva in peptides produced by a widespread group of filamentous fungi indicates the possibility of a terrestrial biotic source for the α-AIB observed in some meteorites. We measured the amino acid distribution and stable carbon and nitrogen isotopic composition of four α-AIB-containing fungal peptides and compared this data to similar meteoritic measurements. We show that the relatively simple distribution of the C(4) and C(5) amino acids in fungal peptides is distinct from the complex distribution observed in many carbonaceous chondrites. We also identify potentially diagnostic relationships between the stable isotopic compositions of pairs of amino acids from the fungal peptides that may aid in ruling out fungal contamination as a source of meteoritic amino acids.     

Galaxy Clusters as Probes for Matter in the Universe

Galaxy clusters are ideal tracers of the large-scale structure and evolution of the universe. They are thus good probes for the matter content of the universe, the existence of dark matter, and for the statistics of the large-scale structure of the matter distribution. X-ray observations provide a very effective tool to characterize individual galaxy clusters as well as the cluster population. With the detailed analysis of X-ray observations of galaxy clusters the matter composition of clusters is obtained which can be taken as representative of the matter composition of the universe. Based on galaxy cluster surveys in X-rays a census of the galaxy cluster population and statistical measures of the spatial distribution of clusters is obtained. Comparison of the results with predictions from cosmological models yields interesting cosmological model constraints and in particular favours a low density universe.     

Education curricula of the UN-affiliated regional Centres for Space Science and Technology Education

Since 1988 the United Nations, through its Programme on Space Applications, has been supporting the establishment and operation of regional Centres for Space Science and Technology Education in Africa, Asia and the Pacific, Latin America and the Caribbean, and Western Asia. Simultaneously, education curricula have been developed for remote sensing and geographic information systems, satellite communications, satellite meteorology and global climate, and space and atmospheric science. The report briefly reviews these developments and highlights the most recent updated education curricula in the four disciplines that have been made available in 2002, in the six official languages of the United Nations, for implementation at the regional centres and beyond.     

未来机载雷达中具有高精度测距能力的新HPRF模式

已研究了一种新的雷达模式，它可以不模糊地估算目标速度并能通过IPRF模式中的脉冲时间延迟估算距离。要实现这点，距离门宽度要减至近乎机载目标（比如战斗机）的距离向长度。与普通HPRF模式不同的是，在不模糊距离中要有多个可辨别的距离门。距离模糊的分辨则由脉冲串至脉冲串间的脉冲重复频率变化来进行。模糊分辨的算法要考虑到这样一个事实，即在PRF变化期间，目标能移至下一个距离门或跨过一个或更多的相邻距离门。此外，可以在算法中采用不模糊速度测量来补偿目标距离徙动以减少虚警率。     

Buffering Fuzzy Maps in GIS

In this paper, we show how standard GIS operations like the complement, union, intersection, and buffering of maps can be made more flexible by using fuzzy set theory. In particular, we present a variety of algorithms for operations on fuzzy raster maps, focusing on buffer operations for such maps. Furthermore, we show how widely-available special-purpose hardware (in particular, z-buffering in graphics hardware) can be used for supporting buffer operations in fuzzy geographic information systems (GIS).     

Comparison of remote sensing experiments from airborne and space platforms

Recent technological advances in the development of instruments and platforms like aircraft, balloons, satellites, the space station and, very recently, Zeppelin dirigibles, have opened up many new applications for remote sensing. This paper is an attempt to summarise and compare advantages and disadvantages as well as limitations, restrictions and perspectives of passive remote sensing instruments used on the different platforms and it should help to select the best platform for a special application for Earth observation.