Magnetic energy storage and the thermal versus non-thermal hard X-ray hypotheses

We demonstrate by using elementary electromagnetic theory that flare mechanisms that require pre-flare energy storage, that is inductive energy storage, are incapable of accelerating sufficient electrons to satisfy the “non-thermal” hard X-ray hypothesis and are therefore “thermal” flare mechanisms within the context of the “thermal hypothesis”.     

Analysis of gravity-wave induced instabilities and turbulence viscosity parameters from optical emissions

The effects of gravity waves on OH and 5577 0I emissions have been used to investigate (1) the possible production of “secondary” waves or “ripples” by a “primary” wave; (2) the possible application of such observed optical emissions for computing atmospheric parameters such as turbulence viscosity in the mesospheric regions.     

Ionospheric electron heating by a rocket borne electron accelerator

A “mother-daughter” rocket code-named “Electron 2” was launched from And?ya, Northern Norway in November, 1978. The “daughter”, carrying a 10 keV electron accelerator, was separated from the “mother” payload with a speed of 0.4 m/s. A series of plasma diagnostic instruments were included on the “mother” to study effects produced by the interaction between the electron beam and the ionospheric plasma. Results obtained by two different plasma probes are presented. It was found that pronounced changes in the ambient electron population took place in regions penetrated by the electron beam. Estimates of the dimensions of the disturbed region are presented.     

Systems for long duration flights

This paper describes the systems for long duration flights developed in Japan for scientific observations. Much efforts have been expended to evolve systems for long duration flights in Japan, by controlling the balloon trajectories with a knowledge of wind pattern at high altitudes over Japan. These systems called “Cycling Balloon”, “Boomerang Balloon” and “New Boomerang Balloon” have been successfully used for the observations by keeping the balloons close to the balloon station.“Relay Balloon” is another system to extend the telemetry range by using an additional balloon as a relay station to link the telemetry from the main balloon.Some detailes of the exhaust valve, ascent meter and automatic level control devices used for the balloon control are also described in the paper.     

Retrieval of aerosol optical characteristics from polarization measurements of reflected solar radiation above the oceans

The reflected near infrared solar radiation observed from space above the oceans is due mainly to the atmosphere scattering, as the ocean surface is nearly black. The molecular Rayleigh contribution is also minimized at infrared wavelengths and it can be evaluated. It is shown that the degree of polarization is much more sensitive to the aerosol properties than the radiance. Measurements of polarization at two wavelengths and with an angular scanning are simulated and an inversion algorithm is proposed. It aims at finding an “equivalent aerosol model,” which reproduces the optical thickness and the asymmetry factor of the actual aerosol at all wavelengths in the solar spectrum.     

Towards the automated operations of large distributed satellite systems. Part 2: Classifications and tools

Recent developments have seen a trend towards larger constellations of spacecraft, with some proposals featuring constellations of more than 10.000 satellites. While similar concepts for large constellations already existed in the past, traditional satellite deployments hardly ever feature groups of more than 100 satellites. This trend towards considerably larger satellite numbers originates from non-traditional design and operations of spacecraft by non-traditional space companies. The evolution in the space sector, precipitated by new players, is often referred to as “Space 4.0” or “New Space”. It necessitates a rethinking of the way satellites and satellite constellations are planned, designed, and operated. New operational paradigms are needed to enable automatic, optimal task definition, and scheduling in a holistic approach.This is the second of two companion papers that investigate the operations of distributed satellite systems. This second article investigates the classification of distributed satellite systems and evaluates commercial tools for automated spacecraft operations, whereas the first article performed a survey of conventional and “new space”operations of spacecraft constellations.Classification metrics for constellations are derived and evaluated with respect to their informative value concerning the operation, the automation, and the scalability of the constellation. The proposed classification system is applied to the Dove and RapidEye constellation and allows for a comparison between the presented automation approaches. Commercial tools for automated spacecraft operations are evaluated for several mission task elements, such as orbit control, orbit maintenance, and collision avoidance. Subsequently, the trends, benefits, and standardization needs for operational automation are identified.     

卫星图像零树编码及其效果分析

采用嵌套零树小波编码 (EZW)算法的核心——零树概念和连续逼近量化的思想设计了一个编码器 ,对卫星图像 (小波分解后 )进行压缩实验 ;分析了卫星图像 (小波分解后 )进行零树编码的压缩效果。设计的编码器采用六符号的零树符号集 ,从而把 EZW算法的主过程和副过程合并在一起 ,使得算法流程易于实现。对零树符号流进行无损编码时 ,对比了多种编码方案且未采用适应性算术编码 ,并依据实验结果推荐了较好的无损编码方法。     

砷化镓功率场效应管早期烧毁的失效分析

采用扫描俄歇微探针、扫描电子显微镜、电子探针微区分析仪和Ｘ射线透射仪等多种分析手段分析了一种Ｃ波段砷化镓功率场效应管早期烧毁失效的现象。初步建立了烧毁失效的模式,给出了相应的失效频数分布及其表面形貌状态。分析结果指出,烧毁失效模式中源一漏烧毁占较大的比例;其次是由于材料及器件制备工艺过程不完善而引起的空气桥烧毁,热斑烧毁,源或漏极条边缘毛刺、芯片表面缺陷、沾污和不可动多余物引起的烧毁失效。文章就烧毁失效的机理进行了分析和讨论。     

Calibration of the VIS-channel of meteosat-2

The “VIS-channel” (the channel is sensitive between about .4 and 1.1 μm wavelength) of the European geostationary satellite Meteosat-2 is calibrated by the method of “vicarious calibration by means of calculated radiances”. The calibration constant, which connects the 6-bit-counts of the VIS-channel of the Meteosat-2 with the corresponding “effective radiances” is determined to be c_SAT = 2.3 W·m^?2·sr^?1/count with an accuracy of ± 10% (preliminary values). The calibration constant is valid for “gain 0” and the period until October 1981. The result means, that the VIS-channel of Meteosat-2 at the beginning of its lifetime is about 15% more sensitive than that of Meteosat-1 was at its end.     

航天测绘发展现状与展望

航天测绘是全球基础测绘的主要手段,包括卫星地形测量、卫星重力测量、卫星磁力测量、卫星测高、卫星海洋测量等。航天测绘工程的发展经历了“返回型测绘卫星”工程、“传输型测绘卫星”工程和部分“集成型测绘卫星”工程。首先梳理了国际卫星测量的发展历史和现状,阐述了我国航天测绘各个阶段所发挥的作用,并分析了存在的问题,最后对航天测绘的未来发展提出了思路。     

NMA survey of CO and HCN emission from nearby active galaxies

The Nobeyama Millimeter Array has been used to map CO(1-0) and HCN(1-0) emission in nearby Seyfert galaxies. A wide variety of molecular gas distributions are found, and there appears to be no “typical” gas distribution either in type-1 Seyferts or type-2s. All the gas distributions and kinematics in the observed Seyferts can be understood as a response to a non-axisymmetric potential in the central regions, suggesting that a small scale (a few 100 pc — a few kpc) distortion of the underlying potential is necessary for Seyfert activity, although it is not a sufficient condition. Circumnuclear star formation in the host of the observed Seyferts can occur via gravitational instabilities of the molecular gas, as in the case of star forming regions in non-Seyfert galaxies. Our results may support the idea that the host galaxies of Seyferts (both type-1s and 2s) and non-Seyferts are the same in terms of the fuel and trigger of star formation. Near the center of Seyfert nuclei (r < a few 100 pc), we find that the molecular gas tends to be gravitationally stable. We find that the R_HCN/CO value ranges over an order of magnitude, from 0.086 to 0.6 among Seyfert galaxies. It seems that the presence of kpc scale jet/outflows is related to the extremely high R_HCN/CO values.     

Validation of nimbus-7 temperature-humidity infrared radiometer estimates of cloud type and amount

Estimates of clear and low, middle and high cloud amount in fixed geographical regions approximately (160km)² are being made routinely from 11.5μm radiance measurements of the Nimbus-7 Temperature-Humidity Infrared Radiometer (THIR). The purpose of validation is to determine the accuracy of the THIR cloud estimates. Validation requires that a comparison be made between the THIR estimates of cloudiness and the “true” cloudiness. The validation results reported in this paper use human analysis of concurrent but independent satellite images with surface meteorological and radiosonde observations to approximate the “true” cloudiness. Regression and error analyses are used to estimate the systematic and random errors of THIR derived clear amount.     

Evaluating the robustness of the enantioselective stationary phases on the Rosetta mission against space vacuum vaporization

The European Space Agency’s Rosetta mission was launched in March 2004 in order to reach comet 67P/Churyumov–Gerasimenko by August 2014. The Cometary Sampling and Composition experiment (COSAC) onboard the Rosetta mission’s lander “Philae” has been designed for the cometary in situ detection and quantification of organic molecules using gas chromatography coupled to mass spectrometry (GC–MS). The GC unit of COSAC is equipped with eight capillary columns that will each provide a specific stationary phase for molecular separation. Three of these stationary phases will be used to chromatographically resolve enantiomers, as they are composed of liquid polymers of polydimethylsiloxane (PDMS) to which chiral valine or cyclodextrin units are attached. Throughout the ten years of Rosetta’s journey through space to reach comet 67P, these liquid stationary phases have been exposed to space vacuum, as the capillary columns within the COSAC unit were not sealed or filled with carrier gas. Long term exposures to space vacuum can cause damage to such liquid stationary phases as key monomers, volatiles, and chiral selectors can be vaporized and lost in transit. We have therefore exposed identical spare units of COSAC’s chiral stationary phases over eight years to vacuum conditions mimicking those experienced in space and we have now investigated their resolution capabilities towards different enantiomers both before and after exposure to space vacuum environments. We have observed that enantiomeric resolution capabilities of these chiral liquid enantioselective stationary phases has not been affected by exposure to space vacuum conditions. Thus we conclude that the three chiral stationary phases of the COSAC experiment onboard the Rosetta mission lander “Philae” can be considered to have maintained their resolution capacities throughout their journey prior to cometary landing in November 2014.     

The winter anomaly of 1983/84 as observed in the A3-absorption and 5 kHz atmospherics in Central Europe

The MAP/WINE winter 1983/84 is studied using the LF-MF-HF A3 absorption and 5 kHz atmospherics observed in Czechoslovakia and some other data. The “normal” winter anomaly in Central Europe is developed well in this winter (maximum in mid-January) and appears to be “free of geomagnetic contamination”. The stratospheric warming activity and related changes of prevailing zonal wind in the lower thermosphere in February and March 1984 are followed by decreases of absorption of radio waves. It agrees with our results from preceding winters /1/.     

Plasma effects in the formation,evolution and present configuration of the Saturnian ring system

The Voyager 1 and 2 observations of the fine structure of the Saturnian ring system demonstrate the importance of electric forces in controlling the dynamics of fine (charged) dust in the rings. A new theory (“gravito-electrodynamics”) which combines the electric and the gravitational forces on these grains leads to natural explanations of a number of observed ring phenomena. If plasma processes play a significant role in the dynamics of the ring system at the present time, it is difficult to avoid the conclusion that they also played an important and perhaps crucial role at cosmogonic times during the emplacement and subsequent condensation of the initial dusty plasma. We believe that the Saturnian ring system represents a “time-capsule” containing vital clues about the physical processes operating during the early stages of its formation. We will show that both its overall structure as well as its fine structure, as determined by Voyagers 1 and 2, indicate the crucial importance of plasma processes in its formation and subsequent evolution.     

Quasistationary outflow of gases from solar active regions

The author's finding that active regions are sources of relatively slow and approximately radial quasistationary corpuscular streams is confirmed by using the fact that active regions are closely connected with coronal holes. Furthermore, attention is paid to numerous papers according to which the active regions characterized by enhanced and prolonged chromospheric (flare) activity are also sources of quasistationary corpuscular streams. Velocities of gases in these streams are higher than velocities of gases in streams from “quiet” active regions.On the basis of all these studies it is suggested that the origin of outflow of plasma from “quiet” active regions and from active regions with enhanced flare activity is the same and is due to some continuous non-stationary processes in the active regions. The velocity of gases in all these streams grows with increasing continuous flare activity in the active regions.It is concluded that quasistationary corpuscular streams from active regions with enhanced flare activity are important sources of cosmic rays from the sun.     

RIO: the R-process isotope observer

Our galaxy is filled with a “gas” of relativistic nuclei and electrons – the galactic cosmic rays (GCRs). The source of GCR nuclei is unknown, but there is a general consensus among high-energy astrophysicists that GCRs are accelerated by supernova (SN) shocks in the interstellar medium. The evidence in support of this picture is strong but indirect. However, the fact that the cosmic-ray spectrum extends continuously, without steps or peaks, to more than five orders of magnitude in energy beyond the limit of SN shock acceleration appears to be incompatible with this picture, at least without extreme fine-tuning of models. A “smoking gun” is needed to definitively establish that SN shocks are indeed the accelerator of GCRs. If GCRs are accelerated in SN shocks, they will be enhanced in freshly-synthesized r-process material. We are currently studying the R-process Isotope Observer (RIO) as a Mission of Opportunity for the International Space Station. RIO will make the first measurements of the isotopic abundances of the “ultraheavy” GCRs (those in the range 32 ⩽ Z ⩽ 42) and will determine the fractional contribution of freshly-synthesized r-process material in GCRs through the measurement of several key isotopic ratios.     

Use of data from meteorological satellites in long-range weather forecasting

In the Soviet Union experiments on obtaining meteorological information by means of man-made Earth's satellites were initiated in 1966 (the “Meteor” meteorological system).Starting with 1975 the launches of the “Meteor-2” updated meteorological satellites of the second generation were carried out. The detailed information about the Soviet meteorological satellite system can be found in [9].Below, the problems concerning the use of satellite data in schemes of long-range weather forecasts are considered. Particular attention is paid to the role of external sources of energy. The role of cloud cover over the oceans is emphasized as a heat influx regulator in the process of absorption radiant solar heat by the ocean. The dynamic and statistical method of ocean heat memory parameterization is stated.     

电子环束流对航天器表面电位和等离子体鞘层的影响

采用二维三分量静电粒子模拟程序研究了电子环束流对低轨道磁化等离子体中运行的航天器表面电位和等离子体鞘层结构的影响.当有电子束流平行磁场入射时,航天器表面所带负电位的绝对值将增大.电子束流的速度和密度的增加将使航天器表面负电位绝对值增加很快.与此同时等离子体鞘层的尺度也将增大,形状将由向尾部延伸的“泪滴”状变成向两侧展开的“机翼”状.当电子环束流以相对于磁场成一定角度斜入射时,由于磁场的约束作用,航天器表面负电位的绝对值将随入射角增大而减小.