Deep Space Flight and Communications: Exploiting the Sun as a Gravitational Lens

Springer Science & Business Media, 09.06.2009. - 402 страница

The majority of books dealing with prospects for interstellar flight tackle the problem of the propulsion systems that will be needed to send a craft on an interstellar trajectory. The proposed book looks at two other, equally important aspects of such space missions, and each forms half of this two part book.

Part 1 looks at the ways in which it is possible to exploit the focusing effect of the Sun as a gravitational lens for scientific missions to distances of 550 AU and beyond into interstellar space. The author explains the mechanism of the Sun as a gravitational lens, the scientific investigations which may be carried out along the way to a distance of 550 AU (and at the 550 AU sphere itself), the requirements for exiting the Solar System at the highest speed and a range of project ideas for missions entering interstellar space.

Part 2 of the book deals with the problems of communicating between an interstellar spaceship and the Earth, especially at very high speeds. Here the author assesses a range of mathematical tools relating to the Karhunen-Loève Transform (KLT) for optimal telecommunications, technical topics that may one day enable humans flying around the Galaxy to keep in contact with the Earth. This part of the book opens with a summary of the author’s 2003 Pešek Lecture presented at the IAC in Bremen, which introduces the concept of KLT for engineers and ‘newcomers’ to the subject. It is planned to include a DVD containing the full mathematical derivations of the KLT for those interested in this important mathematical tool whilst the text itself will contain the various results without outlines of the mathematical proofs. Astronautical engineers will thus be able to see the application of the results without getting bogged down in the mathematics.

Шта други кажу -Напишите рецензију

Нисмо пронашли ниједну рецензију на уобичајеним местима.

Садржај

 So much gain at 550 AU 3 12 The minimal focal distance of 550 AU for electromagnetic Waves 4 13 The antenna gain of the gravitational lens of the Sun 7 14 The combined total gain upon the FOCAL spacecraft 9 16 Requirements on the image size and antenna beamwidth at the spacecraft distance z 10 17 Angular resolution at the spacecraft distance z 11 18 Spatial resolution at spacecraft distance z 14 Scientific investigations along the way to 550 AU 17
 112 Uniform motion 185 113 Decelerated motion 188 114 Checking the KLT of decelerated motion by Matlab simulations 194 115 Total energy of the noisy signal from relativistic spaceships in decelerated and uniform motion 195 exploiting the KLT to detect an alien spaceship approaching the Earth in decelerated motion 199 117 References 200 KLT of radio signals from relativistic spaceships in hyperbolic motion 203 123 Total energy of signals from relativistic spaceships in hyperbolic motion 205

 22 Visible and infared stellar parallaxes 18 222 Age of the Galaxy 19 224 Stellar evolution 20 225 Targets of opportunity 22 232 Astronomy 24 233 Cosmology 25 234 Solar system studies 26 241 Dust 27 242 Plasma and energetic particle distributions 28 245 Plasma waves 29 26 References 30 Magnifying the nearby stellar systems 33 33 Keplerian theory of simple hyperbolic flybys 36 34 The flyby of the Sun performed by the FOCAL spacecraft 43 35 References 45 Astrodynamics to exit the solar system at the highest speed 47 421 Elementary background planar problem 48 422 Optimization of a single Jupiter flyby 49 423 Two optimized Jupiter flybys plus one intermediate Sun flyby 50 43 A chemically powered closeSun flyby? 51 44 Theory of the Sun Flyby enhanced by a perihelion boost 52 45 Determining the perihelion boost by knowing the target star the time to get 550 AU and the Sun approach 53 46 References 57 SETI and the FOCAL space mission 58 52 The narrowband assumption SETI 60 53 A short introduction to the KLT 63 54 Mathematics of the KLT 64 advantages of the KLT for the FOCAL space mission 67 GLSETI gravitational lensing SETI Receiving far ETI signals focused by the gravity of other stars 71 62 Only two types of SETI searches from the Earth up to 2001 72 623 Searches 73 625 Allsky survey 74 626 Common requirements 75 632 Summary 80 64 Maccones equation relating to 1 magnification of lensing star 2 distance of the ET transmitter and 3 power of the ET transmitter 81 the Search for ExtraTerrestrial Visitation 83 66 References 84 The gravitational lenses of Alpha Centauri A B C and of Barnards Star 85 72 The Suns gravity+plasma lens as a model for the nearby stars 86 73 Assumed data about Alpha Centauri A B C and Barnards Star 90 74 Gravitational lens of the naked Sun 93 75 Gravitational lens of the naked Alpha Centauri A 98 76 Gravitational lens of the naked Alpha Centauri B 101 77 Gravitational Lens of the naked Alpha Centauri C Proxima 104 78 Gravitational lens of the naked Barnards Star 107 79 Conclusions 110 The Coronal Plasma pushing the focus of the gravity+plasma lens far beyond 550AU 113 82 The refraction of electromagnetic waves in the Sun Coronal Plasma 115 83 Summary of the Sun pure gravity naked Sun lightbending theory 116 focal axis intercept for any ray passing at distance b from the Sun 118 85 Asymptotic z straight light path 122 closeSun middistance and atinfinity LK and F Corona respectively 123 87 Focal distance vs height and minimal focal distance for any assigned frequency 127 88 The two causes of the gravity+plasma lens of the sun 130 89 Observing frequencies for the closeSun middistance and atinfintity approxiamtions 131 810 References 134 NASAs Interstellar Probe ISP20102070 and the Cosmic Microwave Background CMB 135 2010 to 2055 136 93 Looking at the 2728 K Cosmic Microwave Backround through the Suns gravity lens by virtue of NASAs Interstellar Probe ISP 137 94 The effective minimal focal distance for the gravity+plasma lens looking at the 27K Cosmic Microwave Background is 763 AU which NASAs Int... 142 95 Improving COBEs angular resolution by nine orders of magnitude by looking at the 27K Cosmic Microwave Background by virtue of NASAs Int... 145 96 Conclusions 146 98 References 147 KLToptimized telecommunications 148 A simple introduction to the KLT 151 103 A heuristic derivation of the KL expansion 152 104 The KLT finds the best basis eigenbasis in Hilbert space spanned by the eigenfunctions of the autocorrelation of Xt 155 105 Continuous time vs discrete time in the KLT 157 just a linear transformation in the Hilbert space 158 The Final Variance theorem 159 108 BAM Bordered Autocorrelation Method to find the KLT of stationary processes only 162 109 Developments in 2007 and 2008 168 1010 KLT of stationary white noise 169 1011 KLT of an ET sinusoidal carrier buried white cosmic noise 170 1012 Analytic proof of the BAMKLT 172 1013 KLT signaltonoise SNR as a function of the final T eigenvalue index n and alien frequencies v 174 1014 How to eavesdrop on alien chat 175 1015 Conclusions 176 1016 Acknowledgments 177 KLT of radio signals from relativistic spaceships in uniform and decelerated motion 180
 124 KLT for signals emitted in asymptotic motion by Matlab simulations 206 125 Checking the KLT of asymptotic hyperbolic motion by motion by Matlab simulations 210 126 Signal total energy as a stochastic process of T 211 preparatory calculations 214 128 KL expansion for the instantaneous energy of the noise emitted by a relativistic spaceship 220 129 Conclusion 221 KLT of radio signals from relativistic spaceships in arbitrary motion 223 132 Arbitrary spaceship acceleration 225 1322 KL expansion of the Gaussian noise emitted by a spaceship having an arbitrary acceleration profile 227 1323 Total noise energy 229 1324 KL expansion of noise instantaneous energy 230 133 Asymptotic arbitrary spaceship acceleration 232 1332 Asymptotic KL expansion for noise 234 1333 Asymptotic total noise energy 236 134 Powerlike asymptotic spaceship 238 1342 Powerlike asymptotic KL expansion for noise 239 1343 Approximated powerlike asymptotic KL expansion for noise 241 1344 Powerlike asymptotic total noise energy 242 1345 Powerlike asymptotic KL expansion for noise instantaneous energy 243 1346 Approximated powerlike asymptotic KL expansion for noise instantaneous energy 246 135 Conclusion 247 136 References 248 Genetics aboard relativistic spaceships 249 142 Diffusion partial differential equation for Xt 250 143 Firstpassage time for Xt 252 144 Relativistic interstellar flight 254 145 Timerescaled Brownian motion 255 146 Genetics 256 147 Relativistic genetics 258 148 A glance ahead 259 149 References 260 Engineering tradeo s for the FOCAL spacecraft antenna 262 Reference 264 FOCAL Sun flyby characteristics 269 Mission to the solar gravitational focus by solar sailing 278 C2 Example sailcraft for SGF mission 282 C3 Trajectory profile for SGF mission 283 C4 Conclusions 290 FOCAL radio interferometry by a tethered system 293 D2 References 296 Interstellar propulsion by Sunlensing 298 E2 Highlights on research areas in interstellar propulsion by Sunlensing 300 light from Sirius naked Sun gravity lens and relevent solar sail size 301 E4 Conclusions 305 Brownian motion and its time rescaling 307 F2 Brownian motion essentials 308 F3 KLT of Brownian motion 310 F4 White noise as the derivative of Brownian motion with respect to time 311 F5 Introduction to time rescaling 313 F7 Time rescaling and Gaussian properties of Xt 315 F8 Orthogonal increments for nonoverlapping time intervals 317 F10 References 324 Maccone First KLT Theorem KLT of all timerescaled Brownian motions 325 G3 Solution of the integral equation for eigenfunctions 328 G4 A simpler formula for Bessel Function order 334 G5 Stability criterion for eigenfunctions 335 G6 References 337 KLT of the Bt2H timerescaled Brownian motion 338 H3 KL expansion of BpHt 341 H4 Total energy of BpHt 346 H5 References 349 Maccone Second KLT Theorem KLT of all timerescaled square Brownian motions 351 13 KLT of any zeromean timerescaled square process 352 14 KLT of square Brownian motion 356 I5 Checking the KLT of the square Brownian motion by Matlab simualtions 361 KLT of the B²t²ᵸ timerescaled square Brownian motion 363 J2 Preparatory calculations about B²t²ˣ+¹ 366 J3 KL expansion of the square process B²t²ᵸ 371 J4 Checking the KLT of B²t²ᵸ 373 J5 References 374 A Matlab code for KLT simulations 375 K3 The file input_data_togglem 377 K4 The file Brownian_Autocorrelationm 379 K5 The file process_pathm 380 K7 The file analytic_KLTm 382 K8 The file ANALYTIC_KLT_square_brow_motionm 385 K9 The file ANALYTIC_KLT_uniform_relm 386 K10 Conclusions 389 Index 390 Ауторска права