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In the first Spacelab Mission which will take place in Sept. Oct. 1983 a Metric Camera will be flown as part of the Earth observation payload. The camera will be a modified high quality Aerial Survey Camera.The hardware development is finished and the instrument is already integrated into Spacelab.The application of Metric Cameras in Space, an area which is neglected up to now, can effectively contribute to an improved cartographic coverage of the Earth. The Metric Camera Experiment is a first step to fill this gap which can be realized by utilizing the extended capacities of the Space Transportation System.The paper outlines the scientific objectives of the experiment, describes in detail the camera system and deals with the operation and control philosophy during the mission.  相似文献   

3.
The Search for ExtraTerrestrial Intelligence (SETI) finally has its own full-time telescope. The Allen telescope array (ATA) in Northern California was dedicated on October 11, 2007. This array, which will eventually be composed of 350 small radio antennas, each 6.1 m in diameter, is being built as a partnership between the SETI Institute and the University of California Radio Astronomy Laboratory. Last October, Paul G. Allen (who provided the funds for the technology development and the first phase of array construction) pushed a silver button and all 42 antennas of the current ATA-42 slewed to point in the direction of the distant galaxy M81. Specialized electronic backend detectors attached to the ATA began making a radio map of that galaxy and simultaneously began SETI observations of HIP48573, a G5V star near M81 on the sky and a distance of 264 light years from Earth. The Allen telescope array will greatly improve the speed of conducting SETI searches over the next few decades, and it will allow a suite of different search strategies to be undertaken. This paper summarizes some of the earliest SETI observations from the array, and describes the search strategies currently being planned.  相似文献   

4.
A nanosatellite to investigate the brightness oscillations of massive luminous stars by differential photometry is currently developed by a Canadian/Austrian team within the BRITE (Bright Target Explorer) project. The first Austrian satellite funded by the Austrian Space Program, called TUGSAT-1/BRITE-Austria, builds on the space heritage of the most successful Canadian CanX-2 and MOST missions. The satellite makes use of recent advances in miniaturized attitude determination and control systems. Precision three-axis stabilization by small reaction wheels and a star tracker provides the necessary accuracy for the photometer telescope to the arcminute level. This will provide to the astronomers photometric data of the most massive stars with unprecedented precision; data which cannot be obtained from the ground due to limitations imposed by the terrestrial atmosphere.The paper describes the spacecraft characteristics and the ground infrastructure being established in support of the BRITE mission which will consist of a constellation of up to four nearly identical satellites allowing to carry out long-term observation of stars (magnitude +3.5) not only with respect to brightness variations, but also in different spectrum ranges.  相似文献   

5.
Phoenix--the first Mars Scout mission   总被引:2,自引:0,他引:2  
Shotwell R 《Acta Astronautica》2005,57(2-8):121-134
NASA has initiated the first of a new series of missions to augment the current Mars Program. In addition to the systematic series of planned, directed missions currently comprising the Mars Program plan, NASA has started a series of Mars Scout missions that are low cost, price fixed, Principal [correction of Principle] Investigator-led projects. These missions are intended to provide an avenue for rapid response to discoveries made as a result of the primary Mars missions, as well as allow more risky technologies and approaches to be applied in the investigation of Mars. The first in this new series is the Phoenix mission which was selected as part of a highly competitive process. Phoenix will use the Mars 2001 Lander that was discontinued in 2000 and apply a new set of science objectives and mission objectives and will validate this soft lander architecture for future applications. This paper will provide an overview of both the Program and the Project.  相似文献   

6.
Structures for space applications very often suffer stringent mass constraints. Lightweight structures are developed for this purpose, through the use of deployable and/or inflatable beams, and thin-film membranes. Their inherent properties (low mass and small thickness) preclude the use of conventional measurement methods (accelerometers and displacement transducers for example) during on-ground testing. In this context, innovative non-contact measurement methods need to be investigated for these stretched membranes.The object of the present project is to review existing measurement systems capable of measuring characteristics of membrane space-structures such as: dot-projection videogrammetry (static measurements), stereo-correlation (dynamic and static measurements), fringe projection (wrinkles) and 3D laser scanning vibrometry (dynamic measurements).Therefore, minimum requirements were given for the study in order to have representative test articles covering a wide range of applications. We present test results obtained with the different methods on our test articles.  相似文献   

7.
通过一步高温聚合法制备了一系列含有噁唑环的磺化聚酰亚胺(SPI-X),通过改变磺化二胺与非磺化二胺的比例来控制SPI的磺化程度。采用FT-IR、1HNMR和TG-DSC对合成的单体及聚合物进行了表征。研究了SPI-X膜的稳定性、吸水率、溶胀率及其质子导电性能,并与Nafion(117膜进行比较。结果表明,SPI的磺酸基团分解温度达到270℃,溶胀率则表现出明显的各向异性。SPI-25膜室温下的电导率可达6.0×10-3S/cm,接近相同条件下的Nafion(117膜的质子电导率(9.8×10-3S/cm)。  相似文献   

8.
The paper describes the "SVET" project--a new generation of space greenhouse with small dimensions. Through the use of a minicomputer, "SVET" is fully capable of automatically operating and controlling environmental systems for higher plant growth. A number of preliminary studies have shown the radish and cabbage to be potentially important crops for CELSS (Closed Environmental Life Support System). The "SVET" space greenhouse was mounted on the "CRYSTAL" technological module docked to the Mir orbital space station on 10 June 1990. Soviet cosmonauts Balandin and Solovyov started the first experiments with the greenhouse on 15 June 1990. Preliminary results of seed cultivation over an initial 54-day period in "SVET" are presented. Morphometrical characteristics of plants brought back to Earth are given. Alteration in plant characteristics, such as growth and developmental changes, or morphological contents were noted. A crop of radish plants was harvested under microgravity conditions. Characteristics of plant environmental control parameters and an estimation of functional properties of control and regulation systems of the "SVET" greenhouse in space flight as received via telemetry data is reported.  相似文献   

9.
The different acceleration components on the ISS that are responsible for the generation of convective motions in a fluid cell either in the presence of density gradients or in quasi-isodense processes, are analyzed. The NASA measurements of the quasi-steady and periodic acceleration on the ISS are considered and their effects on fluid-dynamic experiments are computed and discussed under different assumptions. In particular, numerical simulations are carried out to identify the relative importance of linear and pendular accelerations, due to possible rotations of the P/L around its center of mass. The effects caused by variable accelerations created by an isolation mount that exhibits an attenuation factor not constant within the payload volume, caused by the reaction forces of the umbilicals, are computed and analyzed.  相似文献   

10.
G. Russo   《Acta Astronautica》2009,65(9-10):1196-1207
The first dropped transonic flight test (DTFT) of the USV Program, performed with Castor, the first of the two spacecrafts developed within the USV Program, was performed on Saturday 24th February 2007, from Tortolì Airport in Sardinia.At 8:30 a.m. the 340 000 m3 stratospheric balloon lifted off from the East coast of Sardinia, bringing the flying test bed (FTB) up to 20.2 km before release within the isolated sea polygon controlled by Italian air force test range in Salto di Quirra (PISQ). The mission ended at 10:30 a.m. with the splash-down of the space vehicle.The flight itself was very good, with a nose-up manoeuvre under transonic conditions, reaching a maximum Mach as high as 1.08. The mission target was completely achieved as some 2 million measures were taken related to flight data, housekeeping, as well as 500 aerodynamic and structural experimental sensors. Unfortunately, the vehicle has been damaged more than expected during splash-down.Many national and international institutions and industries contributed to the mission carrying out, under the supervision and technical guide of CIRA: Italian Space Agency, Italian Air Force, Italian Navy, Italian Civil Aviation Authority, Italian Company for Air Navigation Services, Port Authorities, European Space Agency, Techno System Dev., Vitrociset, Carlo Gavazzi Space, Space Software Italia, Alcatel Alenia Space Italy, ISL-Altran Group.The paper reports the actual status of post-flight data analysis.  相似文献   

11.
The combination of large membranes and light-weight deployable booms, often called a gossamer structure, has enabled innovative space missions, such as solar sailing, to become possible. Though many designs have been proposed and demonstrated, two problems remain regarding the folding patterns of the membranes. The first problem involves considering the thickness of a membrane to enable uniform and compact folding. The other involves membrane-folding patterns that allow for connecting the membrane to the booms at multiple points and deploying them together while minimizing the use of complex mechanisms. This study proposes three methods that consider the thickness, and two of them can keep the crease lines straight, in contrast to the conventional non-straight crease line solutions. In addition, this study derives one effective design to integrate a membrane with diagonal booms through the systematic classification of existing membrane folding patterns.  相似文献   

12.
We report the first telemetered spaceflight science results from the orbiting Space Environment Survivability of Living Organisms (SESLO) experiment, executed by one of the two 10?cm cube-format payloads aboard the 5.5?kg Organism/Organic Exposure to Orbital Stresses (O/OREOS) free-flying nanosatellite. The O/OREOS spacecraft was launched successfully to a 72° inclination, 650?km Earth orbit on 19 November 2010. This satellite provides access to the radiation environment of space in relatively weak regions of Earth's protective magnetosphere as it passes close to the north and south magnetic poles; the total dose rate is about 15 times that in the orbit of the International Space Station. The SESLO experiment measures the long-term survival, germination, and growth responses, including metabolic activity, of Bacillus subtilis spores exposed to the microgravity, ionizing radiation, and heavy-ion bombardment of its high-inclination orbit. Six microwells containing wild-type (168) and six more containing radiation-sensitive mutant (WN1087) strains of dried B. subtilis spores were rehydrated with nutrient medium after 14 days in space to allow the spores to germinate and grow. Similarly, the same distribution of organisms in a different set of microwells was rehydrated with nutrient medium after 97 days in space. The nutrient medium included the redox dye Alamar blue, which changes color in response to cellular metabolic activity. Three-color transmitted intensity measurements of all microwells were telemetered to Earth within days of each of the 48?h growth experiments. We report here on the evaluation and interpretation of these spaceflight data in comparison to delayed-synchronous laboratory ground control experiments.  相似文献   

13.
This paper analyses potential future collaborative space exploration architectures in terms of 1) the technical capabilities of contributing partners; and 2) the constraints imposed by internal and international politics. We find that when international partners are considered endogenously, the argument for a “flexible path” approach is weakened substantially. This is because international contributions can make “Moon first” economically feasible; and characteristics of proposed “flexible path” approaches may preclude international involvement because of the disproportionate risk that those contributions inherently bear. This could have serious implications for future collaborations. We also note that while there are multiple feasible collaborative architectures, there is currently substantial overlap among the potential niche contributions identified by the international partners.  相似文献   

14.
Blood pressure at 30-sec intervals, heart rate, and percentage increase in leg volume continuously were recorded during a 25-min protocol in the M092 Inflight Lower Body Negative Pressure (LBNP) experiment carried out in the first manned Skylab mission. These data were collected during six tests on each crewman over a 5-month preflight period. The protocol consisted of a 5-min resting control period, 1 min at -8, 1 min at -16, 3 min at -30, 5 min at -40, and 5 min at -50 mm Hg LBNP. A 5-min recovery period followed. Inflight tests were performed at approximately 3-day intervals through the 28-day mission. Individual variations in cardiovascular responses to LBNP during the preflight period continued to be demonstrated in the inflight tests. Measurements of the calf indicated that a large volume of fluid was shifted out of the legs early in the flight and that a slower decrease in leg volume, presumably due to loss of muscle tissue, continued throughout the flight. Resting heart rates tended to be low early in the flight and to increase slightly as the flight progressed. Resting blood pressure varied but usually was characterized by slightly elevated systolic blood pressure, lower diastolic pressure, and higher pulse pressures than during preflight examinations. During LBNP inflight a much greater increase in leg volume occurred than in preflight tests. Large increases occurred even at the smallest levels of negative pressure, suggesting that the veins of the legs were relatively empty at the beginning of the LBNP. The greater volume of blood pooled in the legs was associated with greater increases of heart rate and diastolic pressure and larger falls of systolic and pulse pressure than seen in preflight tests. The LBNP protocol represented a greater stress inflight, and on three occasions it was necessary to stop the test early because of impending syncopal reactions. LBNP responses inflight appeared to predict the degree of postflight orthostatic intolerance. Postflight responses to LBNP during the first 48 hours were characterized by marked elevations of heart rate and instability of blood pressure. In addition, systolic and diastolic pressures were typically elevated considerably both at rest and also during stress. The time required for cardiovascular responses to return to preflight levels was much slower than in the case of Apollo crewmen.  相似文献   

15.
Ten subjects (from 27 to 41 years) have been participated in 32 experiments. They were decompressed from ground level to 40-35 kPa in altitude chamber when breathed 100% oxygen by mask and performed repeated cycles of exercises (3.0 Kcal/min). The intervals between decompressions were 3-5 days. Plasma lipid and erythrocyte membrane fatty acid composition was evaluated in the fasting venous blood before and immediately after hypobaric exposure. There were 7 cases decompression sickness (DCS). Venous gas bubbles (GB) were detected in 27 cases (84.4%). Any significant changes in the fatty acid composition of erythrocyte membranes and plasma didn't practically induce after the first decompression. However, by the beginning of the second decompression the total lipid level in erythrocyte membranes decreased from 54.6 mg% to 40.4 mg% in group with DCS symptoms and from 51.2 mg% to 35.2 mg% (p<0.05) without DCS symptoms. In group with DCS symptoms a tendency to increased level of saturated fatty acids in erythrocyte membranes (16:0, 18:0), the level of the polyunsaturated linoleic fatty acid (18:2) and arachidonic acid (20:4) tended to be decreased by the beginning of the second decompression. Insignificant changes in blood plasma fatty acid composition was observed in both groups. The obtained biochemical data that indicated the simulated extravehicular activity (EVA) condition is accompanied by the certain changes in the blood lipid metabolism, structural and functional state of erythrocyte membranes, which are reversible. The most pronounced changes are found in subjects with DCS symptoms.  相似文献   

16.
基于SPH方法的凝胶推进剂一次雾化仿真研究   总被引:6,自引:0,他引:6  
一次雾化中存在传统网格法难以解决的自由表面、大变形等问题,本文将光滑粒子流体动力学(SPH)方法探索性地应用于凝胶推进剂一次雾化仿真研究。模型粒子数保持在105左右,在高剪切速率下,将凝胶推进剂看作高粘度牛顿流体,研究了撞击速度、撞击角度以及凝胶推进剂物性参数对雾化效果的影响,仿真结果与实验结论基本一致。  相似文献   

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The experiment was performed to ascertain whether man's ability to perform mechanical work would be altered as a result of exposure to the weightless environment. Skylab II crewmen were exercised on a bicycle ergometer at loads approximating 25%, 50%, and 75% of their maximum oxygen uptake while their physiological responses were monitored. The results of these tests indicate that the crewmen had no significant decrement in their response to exercise during their exposure to zero gravity. Immediately postflight, however, all crewmen demonstrated an inability to perform the programmed exercise with the same metabolic effectiveness as they did both preflight and inflight. The most significant changes were elevated heart rates for the same work load and oxygen consumption (decreased oxygen pulse), decreased stroke volume, and decreased cardiac output at the same oxygen consumption level. It is apparent that the changes occurred inflight, but did not manifest themselves until the crewmen attempted to readapt to the 1-G environment.  相似文献   

19.
On Earth thermal conductivity measurements on liquids are difficult to perform because thermal motions due to convection. In microgravity the convection due to buoyancy is evanescent and we expect a strong lowering of Rayleigh and Nusselt numbers. Three low viscosity liquids are selected to carry out the measurements: distilled water (standard) and two silicone oils. We use a modified “hot plate” method with a simplified guard ring, the lowering of convective motions let us to use in the experimental cells larger interplate distances and/or temperature differences than in earth measurements so the accuracy must be improved. Comparisons between Earth and orbit results may help to understand the convection occurrence in our cells. G-300 payload is cantilevered from the experiment mounting plate (EMP) and it includes: four struts, an intermediate plate, a bottom plate with four bumpers, a battery box, an electronic rack and six experimental cells assembled in twin-packs thermally coupled with the EMP. Thermal, vibration and EMI tests have proved that the design satisfies the Nasa requirements and acceptance is in progress.  相似文献   

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