下载  >  课程资源  >  讲义  > Radar evidence of subglacial liquid water on Mars火星上发现水

Radar evidence of subglacial liquid water on Mars火星上发现水 评分:

Science上最新论文,火星上发现水,Radar evidence of subglacial liquid water on Mars。
RESEARCH REPORT A 1 Surface reflection 9140 150 SPLD 160 Basal reflection 170 Along-track distance(km) 15 25 30 Uncalibrated dB B Base of the spld 封梦 10 20 30 40 50 70 Along-track distance(km) Fig. 2. Radar data collected by MARSIS(A)Radargram for MARSIs reflector at about 160 us corresponds to the sPld/basal material interface orbit 10737, whose ground track is shown in Fig 1B. A radargram is a bi- Strong basal reflections can be seen at some locations, where the basal dimensional color-coded section made of a sequence of echoes in which the interface is also planar and parallel to the surface.(B)Plot of surtace and horizontal axis is the distance along the ground track of the spacecraft. basal echo power for the radargram in(A). Red dots, surface echo power the vertical axis represents the two-way travel time of the echo(from a blue dots, subsurface echo power. The horizontal scale is along-track eference altitude of 25 km above the reference datum), and brightness is a distance, as in(a), and the vertical scale is uncalibrated function of echo power. The continuous bright line in the topmost part of The basal echo between 45 and 65 km along-track is stronger than the the radargram is the echo from the surface interface, whereas the bottom surface echo even after attenuation within the SPLD a 8 1550 1500 1450 0 王90四EO=9c 1400 1350 1250 000元8o=0c 15 Distance from area center(km) Distance from area center(km Fig. 3. Maps of basal topography and reflected echo power .(A) Color- values of the normalized basal echo power) outlined in black corresponds coded map of the topography at the base of the sPlD. computed with to the main bright area: the map also shows cther. smaller bright spots respect to the reference datum. The black contour outlines the area in that have a limited number of overlapping profiles. Both panels are which bright basal reflections are concentrated.(B) Color-coded map superimposed on the infrared image shown in Fig. IB, and the value at of normalized basal echo power at 4 MHz. The large blue area(positive each point is the median of all radar footprints crossing that point Orosei et al, Science 361, 490-493(2018) 3 August 2018 3 of 4 RESEARCH REPOR Inside bright reflector Inside bright reflector Outside bright reflector Outside bright reflector d 15 Envelope of dusty water ice model results Dusty water ice model with 205 K basal temperature and 10% dust fraction 40 60 80 Basal permittivity Normalized basal echo power (dB) Basal permittivity(logarithmic scaling) Fig 4. Results of the simulation and retrieved permittivities inside(blue) and outside(brown) the bright reflection area, indicating two (A)Output of the electromagnetic simulations computed at 4 MHz distinct populations of values. These distributions, together with the chart in (figs. S4 and s6). The blue shaded area is the envelope of all curves (A), are used to compute the basal permittivity; for example, the intersection incorporating different amounts of 2o ice and dust along with various basal between the blue curve and the black line gives a basal permittivity value temperatures for the SPLD. The blue line is the curve for a single model of 24.(C)Basal permittivity distributions inside(blue)and outside(brown) (basal temperature of 205 K and 10% dust content), shown for illustration, and the bright reflection area. The nonlinear relationship between the normalized the black horizontal line is the median normalized basal echo power at basal echo power and the permittivity produces an asymmetry(skewness) 4 MHz from the observations. (B)Normalized basal echo power distribution in the distributions of the values REFERENCES AND NOTES 28. A.A. Maryott, E.R. Smith, Table of Dielectric Constants of Pi contract 1/032/12/1. M.P. acknowledges support from the 1. S M. Clifford, J. Gcophys. Res 92, 9135-9152(198 Liquids(no. NBS-514 Nat onal Bureau of Standards. 1951 NASA Postdoctoral Program(2015-2017)at the Ames Research 2. D W.Ashmore, R.G. Bingham, Antarct Sci 26, 758-773(2014).29. M.H. Hecht et al, Science 325 64-67(2009) Center in Moffett Field. California. Author contributions: 3. S P. Carter et al., Geochem. Geophys. Geosyst. 8, 3016(2007) 0. D. C. Catling et al., J. Geophys. Res. Planets 115, EOCEll R.O. devised the data calibration method, produced maps of (2010) subsurface reflectors, developed the electromagnetic propagation 5. Materials and methods are available as supplementary materials. 31. Y.s. Kim, K. P Wo, 5. Maity, S. K Atreya, R. L. Kaiser model, codeveloped the method for data interpretation, and 6. W. M. Farrell et al., Geophys. Res. Lett. 36, L15206(2009) J.Am.Chem.Soc.135.490-4913(2013) cowrote the paper. S.E.L. contributed to the development of the 7. J.J. Plaut et al. Science 316, 92-95(2007) 32. D. A. FIsher, M. H. Hecht, S. P. Kounaves, D. C. Catling, electromagnetic propagation model, codeveloped the method for 8. M. Cartacci, A. Frigeri, R. Orosei, E. Pettinelli, paper presented J. Geophys. Res. Planets 115, ECOE12(2010) data interpretation, and cowrote the paper. E.P. coordinated at the American Geophysical Union Fall Meeting, San 33. J. -asue et al. Space Sci. Rev. 174, 155-212(2013 the writing of the paper, contributed to data analysis interpretation, Francisco, CA. 15 to 19 December 2008 4. C Grima et al. Icarus 212, 96-109(2011) and discussed ideas. A.C. planned and conducted the search for 9. GKA.Oswald, S.P.Gogineni, J. Glaciol 54, 94-106(2008). 35. R Orosei A. Cicchetl, Data files and electromagnetic simulation bright subsurface radar reflectors using raw cata. M. Co.B.C 10. M.J. Siegert, S. Carter, L. Tabacco, S. Popov, D. D. Blankenship, software used in the paper"Radar evidence of subglacial liquid F.D.P. F.F. E.M., and M P contributed text and figures to the Antarct.Sc.17,453-460(2005 water on Mars. Zenodo(2018 ); doi: 10.5281/zendo. 1285179. manuscript and discussed ideas. E.S. contributed to the forward 11. D. E. Smith et al., J. Geophys. Res. 106, 23689-23722(2001) and inverse modeling of the electromagnetic propagation and 12. G. A Neumann et al., Geophys. Res. Lett. 30, 1561(2003) ACKNOWLEDGMENTS scattering and discussed ideas. M Ca, F.C., AF, S.G., R. M, AM 13. C.S. Edwards et al,JGeophys. Res. Planets 116, E10008(2011). We gratefully acknowledge the work of Giovanni Picardi G.M., C N, R N, M.R., dnd R.S. conlribuled lo dala acyuisiliorI and 14.M.T. Zuber et a., Science317.1718-1719(2007) (1936-2015), who served as principal investigator of MARSIS. Tha analysis and discussec ideas. Competing interests: The authors 15. J. Li et al., J Geophys. Res Planets 117, E04006(2012) MARSIS instrument and experiment were funded by the italian declare no competing interests. Data and materials availability: 16 M 1 I itvak et al, 1. Geophys. Res Planets 112, F03S13( 0007). Space Agency and NASA and developed by the University of Rome.I Data reported in this paper, scripts used to model electromagnetic 17. 0. Aharonson et al., J. Geophys. Res. Planets 109, E05004 Italy, in partnership with NASA's Jet Propulsion Laboratory (JPL). propagation, and the output of those scripts are available through the Pasadena, CA. Alenia Spazio(now Thales Alenia Space, Italy) Zenodo research data repository( 35) 18. R. Seu et al., J. Geophys. Res. Planets 112, E05S05(2007) ovided the instrument s digital processing system and 19.R. Seu et a, Science317,1715-1718(2007) integrated the parts and now operates the instrument and SUPPLEMENTARY MATERIALS 20. E. Pettinel i et ai., Rev Geophys. 53, 593-641(2015) experiment. The University of lowa, lowa City, IA, built the 21. S. E Lauro et al., Geophys. Res. Lett. 37, L14201(2010) transmitter for the instrument JPl built the receiver: and www.sciencemag.org/content/361/6401/490/suppl/dcl 22.M.A. Wieczorek. Icarus196.506-517(2008 Astro Aerospace, Carpinteria, CA, built the antenna. This Materials and Methods 23. Z. Zhang et al, J. Gecphys Res Planets 113, E05004(2008). research has made use of NASA's Astrophysics Da: a System Supplementary Tex 24. L. M. Carter et al., Geophys. Res. Lett. 36, L23204(2009) The perceptually uniform color map"broc"was used in this Figs. SI to s6 25. J. Mouginot et al., Icarus 210, 612-625(2010) study to prevent visual disto tion of the data. We thank 26. Y. G Ieglen, V. Palciauskas. Introduction to the Physics of References (36-53) sIg Rocks(Princeton Univ. Press, 1994) We are grateful to S E. Beaupien for careful proofreading of the 13 December 2017: accepted 20 June 2018 27. M. E.Peters, D.D. Blankenship. D. L. Morse, J.Ceophys. Res. manuscript and improvemen: of the English.Funding:This Published online 25 July 2018 Solid earth110.B06303(2005) work was supported by the italian Space Agency (ASl)through I 101126/science. aar7268 Orosei et al, Science 361, 490-493(2018) 3 August 2018 4 of 4 Science

...展开详情
2018-09-24 上传 大小:999KB
举报 收藏
分享
Radar evidence of subglacial liquid water on Mars火星上发现水

Science上最新论文,火星上发现水,Radar evidence of subglacial liquid water on Mars。

立即下载
Guidelines for the management of IT evidence

IT证据管理的指导准则 HB 171—2003 Preface This handbook has been prepared by Committee IT/012, Information Systems, Security and Identification Technology. It is intended for use as a reference document by a variety of audiences, including— a) executives and Boards responsible for ensuring the existence of re

立即下载
Beautiful Evidence

数据可视化开山之作,作者Edward Tufte是数据可视化的先行者

立即下载
机器人Evidence Grid

机器人定位相关 robot Evidence grid 机器人定位、建图、导航

立即下载
matlab ds evidence theory

ds 证据理论 matlab 代码

立即下载
python ds evidence theory code

ds 证据理论 python 代码

立即下载
Evidence-Based Technical Analysis

给予证据分析的量化投资指南.

立即下载
beautiful evidence --- pdf版

数据可视化大师Edward Tufte(爱德华·塔夫特)写的数据可视化著作。《美丽的证据》(获商业周刊2006年最革新的设计书籍赞誉。《美丽的证据》一书使powerpoint作为在一场统计结果的讨论中的一部分。这场讨论不仅有非凡的视觉效果,而且饱含智慧:一场艺术和科学融合的盛会。它归功于作者对两个领域严谨忠实的贡献。

立即下载
Software for Dependable Systems: Sufficient Evidence?

美国顶级权威专家们对各种软件可信技术作出评价。本书由美国国家科学院出版社于2007年出版。

立即下载
Double Jump Stochastic VolatilityModel for VIX Evidence from VVIX

依据VVIX的双跳随机波动模型,论文类,英文版

立即下载
Mobile Forensic Investigations A Guide to Evidence Collection Analysis and epub

Mobile Forensic Investigations A Guide to Evidence Collection Analysis and Presentation 英文epub 本资源转载自网络,如有侵权,请联系上传者或csdn删除 本资源转载自网络,如有侵权,请联系上传者或csdn删除

立即下载
Computer Age Statistical Inference - Algorithms, Evidence and Data Science

大数据时代的统计学 This book takes us on an exhilarating journey through the revolution in data analysis following the introduction of electronic computation in the 1950s. Beginning with classical inferential theories – Bayesian, frequentist, Fisherian – individual chapters take up a series of influential to

立即下载
Computer Age Statistical Inference: Algorithms, Evidence, and Data Science

经典统计学图书:Cambridge University Press, 2016 系统介绍了计算机时代的新方法,包括大数据、深度学习等 Computer Age Statistical Inference: Algorithms, Evidence, and Data Science Bradley Efron Trevor Hastie ISBN: 978-1107149892 --------------------------------- 图书主页: https://www.cambridge.org/hk/academic/subjects/statistics-probabi

立即下载
Computer Age Statistical Inference Algorithms, Evidence, and Data Science.zip

Computer Age Statistical Inference Algorithms, Evidence, and Data Science 统计机器学习新书 高清版 介绍有关数据经典书籍

立即下载
Computer Age Statistical Inference: Algorithms,Evidence,and Data Science.

1 Algorithms and Inference 3 1.1 A Regression Example 4 1.2 Hypothesis Testing 8 1.3 Notes 11 2 Frequentist Inference 12 2.1 Frequentism in Practice 14 2.2 Frequentist Optimality 18 2.3 Notes and Details 20 3 Bayesian Inference 22 3.1 Two Examples 24 3.2 Uninformative Prior Distributions 28 3.3 Flaw

立即下载
COFEE计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)

微软的一款名为COFEE的工具近日已经泄漏到网上,对于很多人来说这是一款非常陌生的微软产品,这是微软向国际刑警组织免费提供的证据提取工具,并不面向普通用户推广。 COFEE 全称为“计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)”,微软是这样描述的COFEE的:“有了COFEE,没有合适的计算机取证能力的执法机构也可以轻松、可靠而且高效地收集现场证据。一个只有最基础的计算机知识的人也可以在不超过10分钟的时间里学会如何使用配置好的COFEE设备,执法人员可以像专家一样收集重要的犯罪证据,其复杂程度就像将USB插入计算机那

立即下载
计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)(part 1)

COFEE全称为“计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)”,是一款微软免费提供给国际刑警组织使用的证据提取工具,微软是这样描述的COFEE的:“有了COFEE,没有合适的计算机取证能力的执法机构可以轻松、可靠而且高效地收集现场证据。一个只有最基础的计算机知识的人也可以在不超过10分钟的时间里学会如何使用配置好的COFEE设备,执法人员可以像专家一样收集重要的犯罪证据,其复杂程度就像将USB插入计算机那样。”

立即下载
计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)(part 2)

COFEE全称为“计算机在线法庭科学证据提取器(Computer Online Forensic Evidence Extractor)”,是一款微软免费提供给国际刑警组织使用的证据提取工具,微软是这样描述的COFEE的:“有了COFEE,没有合适的计算机取证能力的执法机构可以轻松、可靠而且高效地收集现场证据。一个只有最基础的计算机知识的人也可以在不超过10分钟的时间里学会如何使用配置好的COFEE设备,执法人员可以像专家一样收集重要的犯罪证据,其复杂程度就像将USB插入计算机那样。” 简单地说,COFEE就是一种是形似U盘的提取工具,COFEE包含了超过150个信息收集、密码破解、网络嗅探

立即下载
funds of hedge funds

1 Rank alpha funds of hedge funds 2 Funds of hedge funds: bias and persistence in returns 3 Replication and evaluation of funds of hedge funds returns 4 Performance, size, and new opportunities in the funds of hedge funds industry 5 Optimal fund of funds asset allocation: hedge funds, CTAs, and REIT

立即下载
Encyclopedia of Forensic Sciences

The Encyclopedia of Forensic Sciences is the first resource to provide comprehensive coverage of the core theories, methods, techniques, and applications employed by forensic scientists. One of the more pressing concerns in forensic science is the collection of evidence from the crime scene and its

立即下载