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151.
152.
Aubrey AD Chalmers JH Bada JL Grunthaner FJ Amashukeli X Willis P Skelley AM Mathies RA Quinn RC Zent AP Ehrenfreund P Amundson R Glavin DP Botta O Barron L Blaney DL Clark BC Coleman M Hofmann BA Josset JL Rettberg P Ride S Robert F Sephton MA Yen A 《Astrobiology》2008,8(3):583-595
The Urey organic and oxidant detector consists of a suite of instruments designed to search for several classes of organic molecules in the martian regolith and ascertain whether these compounds were produced by biotic or abiotic processes using chirality measurements. These experiments will also determine the chemical stability of organic molecules within the host regolith based on the presence and chemical reactivity of surface and atmospheric oxidants. Urey has been selected for the Pasteur payload on the European Space Agency's (ESA's) upcoming 2013 ExoMars rover mission. The diverse and effective capabilities of Urey make it an integral part of the payload and will help to achieve a large portion of the mission's primary scientific objective: "to search for signs of past and present life on Mars." This instrument is named in honor of Harold Urey for his seminal contributions to the fields of cosmochemistry and the origin of life. 相似文献
153.
Adriani A Coradini A Filacchione G Lunine JI Bini A Pasqui C Calamai L Colosimo F Dinelli BM Grassi D Magni G Moriconi ML Orosei R 《Astrobiology》2008,8(3):613-622
The Jovian InfraRed Auroral Mapper (JIRAM) has been accepted by NASA for inclusion in the New Frontiers mission "Juno," which will launch in August 2011. JIRAM will explore the dynamics and the chemistry of Jupiter's auroral regions by high-contrast imaging and spectroscopy. It will also analyze jovian hot spots to determine their vertical structure and infer possible mechanisms for their formation. JIRAM will sound the jovian meteorological layer to map moist convection and determine water abundance and other constituents at depths that correspond to several bars pressure. JIRAM is equipped with a single telescope that accommodates both an infrared camera and a spectrometer to facilitate a large observational flexibility in obtaining simultaneous images in the L and M bands with the spectral radiance over the central zone of the images. Moreover, JIRAM will be able to perform spectral imaging of the planet in the 2.0-5.0 microm interval of wavelengths with a spectral resolution better than 10 nm. Instrument design, modes, and observation strategy will be optimized for operations onboard a spinning satellite in polar orbit around Jupiter. The JIRAM heritage comes from Italian-made, visual-infrared imaging spectrometers dedicated to planetary exploration, such as VIMS-V on Cassini, VIRTIS on Rosetta and Venus Express, and VIR-MS on the Dawn mission. 相似文献
154.
Billings L Cameron V Claire M Dick GJ Domagal-Goldman SD Javaux EJ Johnson OJ Laws C Race MS Rask J Rummel JD Schelble RT Vance S 《Astrobiology》2006,6(5):735-813
The Astrobiology Primer has been created as a reference tool for those who are interested in the interdisciplinary field of astrobiology. The field incorporates many diverse research endeavors, but it is our hope that this slim volume will present the reader with all he or she needs to know to become involved and to understand, at least at a fundamental level, the state of the art. Each section includes a brief overview of a topic and a short list of readable and important literature for those interested in deeper knowledge. Because of the great diversity of material, each section was written by a different author with a different expertise. Contributors, authors, and editors are listed at the beginning, along with a list of those chapters and sections for which they were responsible. We are deeply indebted to the NASA Astrobiology Institute (NAI), in particular to Estelle Dodson, David Morrison, Ed Goolish, Krisstina Wilmoth, and Rose Grymes for their continued enthusiasm and support. The Primer came about in large part because of NAI support for graduate student research, collaboration, and inclusion as well as direct funding. We have entitled the Primer version 1 in hope that it will be only the first in a series, whose future volumes will be produced every 3-5 years. This way we can insure that the Primer keeps up with the current state of research. We hope that it will be a great resource for anyone trying to stay abreast of an ever-changing field. 相似文献
155.
Rain.L 《中国航天(英文版)》2006,(4)
China will launch 6 more Earth observation satellites in the next five years including CBERS-02B, 03, 04 satellites and EDMC constellation satellites A, B and C. A complete national Earth observation system will be established after the successful launch and operation of the above satellites. The information was released by China Center for Resource I Satellite Data and Applications (CRESDA) recently. 相似文献
156.
目前修建的多数机场和公路的刚性道(路)面都铺设一个基层(subbaselayer);从而由双层基础(two-layer foundation)支承着道面板构成一个混凝土板块系统。本文利用双层基础体系上板块的计算推导出一个解析的回归计算、分析道(路)面参数的方法(closed-form procedure)。为了计算道(路)面的表面弯沉,已编制出一个称之为NUS-DEF3的计算机程序,用作回归计算分析的子程序。文中介绍了这个系统的回归算法。该算法是把一个有三个未知数的三元方程组简化为一个简单的非线性方程。它不同于通过最小二乘方迭代求最好的解的常规方法,而是在得出唯一解析解时,从一开始就不需要选择初始模量。该文还用数字范例对三个典型的双层基础上板块的问题做了演示。 相似文献
157.
The emergence of the citric acid cycle is one of the most remarkable occurrences with regard to understanding the origin and evolution of metabolic pathways. Although the chemical steps of the cycle are preserved intact throughout nature, diverse organisms make wide use of its chemistry, and in some cases organisms use only a selected portion of the cycle. However, the origins of this cycle would have arisen in the more primitive anaerobic organism or even back in the proto-metabolism, which likely arose spontaneously under favorable prebiotic chemical conditions. In this context, we report that UV irradiation of formamide in the presence of titanium dioxide afforded 6 of the 11 carboxylic acid intermediates of the reductive version of the citric acid cycle. Since this cycle is the central metabolic pathway of contemporary biology, this report highlights the role of photochemical processes in the origin of the metabolic apparatus. 相似文献
158.
Nicholson WL Ricco AJ Agasid E Beasley C Diaz-Aguado M Ehrenfreund P Friedericks C Ghassemieh S Henschke M Hines JW Kitts C Luzzi E Ly D Mai N Mancinelli R McIntyre M Minelli G Neumann M Parra M Piccini M Rasay RM Ricks R Santos O Schooley A Squires D Timucin L Yost B Young A 《Astrobiology》2011,11(10):951-958
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
159.
Rain.L 《中国航天(英文版)》2006,(4)
The 6th China International Aviation and Aerospace Exhibition (Airshow China 2006) closed on November 5, 2006 after a successful week show. The 6-day Airshow China 2006, beginning from October 31, attracted over 550 aerospace and aviation companies from 33 countries and regions. 相似文献
160.
本文讨论了与飞行中远程巡航导弹通信的需求以及卫星作为中继平台的潜力。国防卫星通信系统Ⅲ(DSCSⅢ)和舰队卫星通信(FLTSATCOM)星至少能够同时为70枚巡航导弹向水面舰只和陆基指挥中心传送200bit的状态信息。DSCSⅢ还可以同是为至少70枚巡航导弹提供准实时有人末制导支持(只要巡航导弹装有共影天线阵)。FLTSATCOM可以为2枚装有全向天线阵的巡航导弹提供相同的能力。这种能力包括传统末段敏感器图象数据,该图象数据的速率为每格每秒40kbits,取决于可实现的图象数据压缩比。本文还论述了指挥员利用这些系统重新瞄准新目标,允许一枚巡航导弹向地面传送一路末段敏感器图象。 相似文献