Free Astronomy Books

This is the updated list of astronomy books available for free download or online reading. These books and papers cover all the areas of astrophysics, cosmology, galactic and extragalactic astronomy, solar and stellar physics, celestial mechanics, planetary science, astrobiology, as well as some popular works. The books are made available free of charge to the reader by their authors or publishers. Here is a categorized directory of astronomy books. This page is updated daily.

1. The Beginning and Evolution of the Universe
   Bharat Ratra, Michael S. Vogeley | arXiv, Published in 2008, 69 pages
2. Stellar Superfluids
   Dany Page, et al. | arXiv, Published in 2013, 88 pages
3. Particle Physics and Inflationary Cosmology
   Andrei Linde | arXiv, Published in 2005, 270 pages
4. Mechanism of the Heavens
   Mary Somerville | J. Murray, Published in 1831, 710 pages
5. Lunar Orbiter Photographic Atlas of the Moon
   D.E. Hughes, J.K. Bowker | Lunar and Planetary Institute, Published in 1971
6. Voyager Encounters Jupiter
   | National Aeronautics and Space Administration, Published in 1979, 48 pages
7. Lectures on Inflation and Cosmological Perturbations
   David Langlois | arXiv, Published in 2010, 56 pages
8. Introduction to Non-Baryonic Dark Matter
   Paolo Gondolo | arXiv, Published in 2004, 51 pages
9. Planetary Theory
   Ernest Brown, Clarence Shook | Cambridge University Press, Published in 1933, 323 pages
10. Black Holes
    P.K. Townsend | arXiv, Published in 1997, 145 pages
11. Textbook on Practical Astronomy
    George Leonard Hosmer | Wiley, Published in 1910, 252 pages
12. Massive Stars and their Supernovae
    F. Thielemann, R. Hirschi, M. Liebendorfer, R. Diehl | arXiv, Published in 2010, 81 pages
13. An Expanded View of the Universe
    | European Southern Observatory, Published in 2011, 54 pages
14. Special Functions: Fractional Calculus and the Pathway for Entropy
    Hans J. Haubold (ed.) | MDPI AG, Published in 2018, 306 pages
15. Introduction to the Theory of Black Holes
    Gerard 't Hooft | Utrecht University, Published in 2009, 49 pages
16. Techniques of Radio Astronomy
    T. L. Wilson | arXiv, Published in 2011, 47 pages
17. Are We Alone?
    Gregg Easterbrook | The Atlantic Monthly, Published in 1988
18. An Introduction to Celestial Mechanics
    Forest Ray Moulton | The MacMillan Company, Published in 1914, 437 pages
19. Practical Astronomy
    George L. Hosmer | John Wiley and Sons Inc., Published in 1925, 314 pages
20. TASI Lectures: Introduction to Cosmology
    Mark Trodden, Sean M. Carroll | arXiv, Published in 2004, 82 pages
21. Dense Matter in Compact Stars
    Andreas Schmitt | arXiv, Published in 2010, 146 pages
22. Ultrahigh Energy Cosmic Rays: Facts, Myths, and Legends
    Luis Alfredo Anchordoqui | arXiv, Published in 2011, 92 pages
23. The Search for Extraterrestrial Intelligence, SETI
    Philip Morrison, John Billingham, John Wolfe | NASA, Published in 1979, 293 pages
24. The Birth And Death Of The Sun
    George Gamow | Dover Publications, Published in 1940, 256 pages
25. Stellar Atmospheres
    J. B. Tatum | , Published in 2006, 302 pages
26. An Introduction to Celestial Mechanics
    Richard Fitzpatrick | The University of Texas at Austin, Published in 2011, 216 pages
27. A New Astronomy
    David Peck Todd | American Book Company, Published in 1906, 437 pages
28. The Practical Astronomer
    Thomas Dick | Seeley, Burnside, and Seeley, Published in 1845, 588 pages
29. High Performance Computing and Numerical Modelling
    Volker Springel | arXiv, Published in 2014, 108 pages
30. The Cosmic Web: Geometric Analysis
    Rien van de Weygaert, Willem Schaap | arXiv, Published in 2007, 129 pages
31. Lopsided Spiral Galaxies
    Chanda J. Jog, Francoise Combes | arXiv, Published in 2008, 75 pages
32. Satellites of Jupiter
    David Morrison | University of Arizona Press, Published in 1982, 983 pages
33. The world according to the Hubble Space Telescope
    Mario Livio | arXiv.org, Published in 2008, 112 pages
34. The Fine-Tuning of the Universe for Intelligent Life
    Luke A. Barnes | arXiv, Published in 2011, 76 pages
35. Large Scale Structure of the Universe
    Alison L. Coil | arXiv, Published in 2012, 43 pages
36. Star-Gazer's Hand-Book
    Henry William Elson | Sturgis & Walton, Published in 1910, 72 pages
37. The Geology of the Terrestrial Planets
    Michael H. Carr | NASA, Published in 1984, 322 pages
38. Introduction to Early Universe Cosmology
    Robert H. Brandenberger | arXiv, Published in 2011, 70 pages
39. Cosmic Rays in Galactic and Extragalactic Magnetic Fields
    F. Aharonian, A. Bykov, E. Parizot, V. Ptuskin, A. Watson | arXiv, Published in 2011, 43 pages
40. Cosmos and Culture: Cultural Evolution in a Cosmic Context
    Steven J. Dick, Mark L. Lupisella | NASA, Published in 2010, 612 pages
41. Practical Astronomy
    P. S. Michie, F. S. Harlow | John Wiley & Sons, Published in 1893, 246 pages
42. Pioneers of Science
    Oliver Lodge | Macmillan and co, Published in 1905, 421 pages
43. Primordial Nucleosynthesis: from precision cosmology to fundamental physics
    F. Iocco, G. Mangano, G. Miele, O. Pisanti, P.D. Serpico | arXiv, Published in 2009, 148 pages
44. Sky Surveys
    S. G. Djorgovski, A.A. Mahabal, A.J. Drake, M.J. Graham, C. Donalek | arXiv, Published in 2012, 62 pages
45. Inflation
    Marieke Postma | NIKHEF, Published in 2009, 53 pages
46. The History of Astrometry
    Michael Perryman | arXiv, Published in 2012, 52 pages
47. Cosmology: The Study of the Universe
    | NASA, Published in 2009, 38 pages
48. An introductory treatise on the lunar theory
    Ernest W Brown | Cambridge University Press, Published in 1896, 312 pages
49. Cosmology and Astrophysics
    Juan Garcia-Bellido | arXiv.org, Published in 2005, 76 pages
50. The Fundamentals of Stellar Astrophysics
    George W. Collins, II | W H Freeman & Co, Published in 2003, 494 pages
51. Observing the Sky from 30S
    Roberto Mura | Wikibooks, Published in 2010, 86 pages
52. Basaltic Volcanism on the Terrestrial Planets
    | Pergamon Press, Published in 1981, 1286 pages
53. A Briefer History of Time: From the Big Bang to the Big Mac
    Eric Schulman | St. Martin's Press, Published in 2004, 207 pages
54. Introduction to Physical Astronomy
    Kenneth R. Koehler | University of Cincinnati, Published in 2010
55. Multi-messenger Astronomy and Dark Matter
    Las Bergstrom | arXiv, Published in 2012, 105 pages
56. Handbook of Space Astronomy and Astrophysics
    Martin V. Zombeck | Cambridge University Press, Published in 2006, 780 pages
57. A Text-book of Astronomy
    George C. Comstock | D. Appleton and company, Published in 1901, 391 pages
58. Short History of Astronomy
    Arthur Berry | John Murray, Published in 1898, 439 pages
59. Dynamics of the Universe in Problems
    Yu. L. Bolotin, et al. | UniverseInProblems.com, Published in 2013, 113 pages
60. Observations of the High Redshift Universe
    Richard S. Ellis | arXiv, Published in 2007, 115 pages
61. The Shape of the Universe
    Gerd Pommerenke | viXra, Published in 2013, 321 pages
62. A Practical Introduction to Numerical Hydrodynamics
    Garrelt Mellema | Leiden University, Published in 2003, 124 pages
63. A Primer for Black Hole Quantum Physics
    R. Brout, S. Massar, R. Parentani, P. Spindel | arXiv, Published in 2007, 178 pages
64. Elementary Mathematical Astronomy
    C. Barlow, G. Bryan | University Correspondence College Press, Published in 1893, 442 pages
65. The First Stars
    Simon C. O. Glover | arXiv, Published in 2012, 72 pages
66. Primordial Magnetogenesis
    Alejandra Kandus, Kerstin E. Kunze, Christos G. Tsagas | arXiv, Published in 2011, 107 pages
67. Supernova Remnants: The X-ray Perspective
    Jacco Vink | arXiv, Published in 2011, 78 pages
68. Traces of Catastrophe
    Bevan M French | Lunar and Planetary Institute, Published in 1998, 120 pages
69. Cosmic Journey: A History of Scientific Cosmology
    N. S. Hetherington, W. P. McCray | American Institute of Physics, Published in 2009, 344 pages
70. The Cosmological Constant
    Sean M. Carroll | arXiv, Published in 2000, 50 pages
71. String Cosmology
    James M. Cline | arXiv, Published in 2007, 47 pages
72. Introduction to Millimeter/Sub-Millimeter Astronomy
    T. L. Wilson | arXiv, Published in 2009, 106 pages
73. An Introduction to Galactic Chemical Evolution
    Nikos Prantzos | arXiv, Published in 2007, 46 pages
74. Gravitational Waves: Sources, Detectors and Searches
    Keith Riles | arXiv, Published in 2012, 79 pages
75. From Cosmic Birth to Living Earths: The Future of UVOIR Space Astronomy
    Julianne Dalcanton, et al. | arXiv, Published in 2015, 176 pages
76. Voyager 1 Encounters Saturn
    | NASA, Published in 1980, 51 pages
77. A practical guide to Basic Statistical Techniques for Data Analysis in Cosmology
    Licia Verde | arXiv, Published in 2008, 52 pages
78. Radiative Gas Dynamics
    David Weinberg | Ohio State University, Published in 2007
79. Hubble 25: A Quarter-Century of Discovery with the Hubble Space Telescope
    Dylan Steele (ed.) | NASA, Published in 2015, 78 pages
80. Planetary Science: A Lunar Perspective
    Stuart Ross Taylor | Lunar and Planetary Institute, Published in 1982
81. Spherical Astronomy
    F. Brünnow | Van Nostrand, Published in 1865, 559 pages
82. General Astronomy
    | Wikibooks, Published in 2009
83. Magnetic Fields, Strings and Cosmology
    Massimo Giovannini | arXiv, Published in 2006, 76 pages
84. Consolidated Lunar Atlas
    Gerald P. Kuiper, et al. | Lunar and Planetary Institute, Published in 1960
85. Galaxy systems in the optical and infrared
    A. Biviano | arXiv, Published in 2008, 60 pages
86. History of Astronomy
    George Forbes | , Published in 1909
87. Curiosities of the Sky
    Garrett Putman Serviss | Harper & Brothers, Published in 1909, 300 pages
88. Views of the Solar System
    Calvin J. Hamilton | , Published in 2008
89. The Beginning and the End: The Meaning of Life in a Cosmological Perspective
    Clement Vidal | arXiv, Published in 2013, 356 pages
90. Resources of Near-Earth Space
    J. S. Lewis, M. S. Matthews | University of Arizona Press, Published in 1993, 977 pages
91. Protostars and Planets
    | Rice University, Published in 2015, 422 pages
92. Astronomy Notes
    Nick Strobel | astronomynotes.com, Published in 2010
93. The Solar Magnetic Field
    Sami Solanki, Bernd Inhester, Manfred Schussler | arXiv, Published in 2010, 83 pages
94. Big Bang Nucleosynthesis and Physics Beyond the Standard Model
    Subir Sarkar | arXiv, Published in 1996, 156 pages
95. A Handbook of Descriptive and Practical Astronomy
    George F. Chambers | Oxford At The Clarendon Press, Published in 1889, 756 pages
96. The Hubble Constant
    Neal Jackson | arXiv, Published in 2014, 48 pages
97. Introduction to Dark Matter Experiments
    R. W. Schnee | arXiv.org, Published in 2011, 64 pages
98. Photographs of Nebulae and Clusters
    James Edward Keeler | University of California Publications, Published in 1908
99. Introductory Lectures on Quantum Cosmology
    J. J. Halliwell | arXiv, Published in 1990, 107 pages
100. An Introduction to Astronomy
     Forest Ray Moulton | The MacMillan Company, Published in 1916, 577 pages
101. Cosmological Evolution of Galaxies
     Isaac Shlosman | arXiv, Published in 2012, 88 pages
102. Lectures on Black Holes, Topological Strings and Quantum Attractors
     Boris Pioline | arXiv, Published in 2007, 103 pages
103. From Chaos to Consciousness: A Brief History of the Universe
     Mike Corwin | Bookboon, Published in 2015, 166 pages
104. To See the Unseen: A History of Planetary Radar Astronomy
     Andrew J. Butrica | NASA History Division, Published in 1996, 301 pages
105. Cosmic Rays and the Search for a Lorentz Invariance Violation
     Wolfgang Bietenholz | arXiv, Published in 2008, 81 pages
106. Astrochemistry: The Issue of Molecular Complexity in Astrophysical Environments
     M. De Becker | arXiv, Published in 2013, 62 pages
107. Through the Telescope
     James Baikie | Adam and Charles Black, Published in 1906, 303 pages
108. Understanding Galaxy Formation and Evolution
     V. Avila-Reese | arXiv, Published in 2006, 50 pages
109. Black-Hole Phenomenology
     Neven Bilic | arXiv, Published in 2006, 58 pages
110. Introduction to Cosmology
     A. D. Dolgov | arXiv, Published in 2009, 58 pages
111. Man's Place in the Universe
     Alfred R. Wallace | Chapman and Hall, Published in 1904, 330 pages
112. Guidebook to the Geology of Barringer Meteorite Crater, Arizona
     David A. Kring | Lunar and Planetary Institute, Published in 2007, 154 pages
113. Advanced Topics in Cosmology: A Pedagogical Introduction
     T. Padmanabhan | arXiv, Published in 2006, 40 pages
114. Why CMB physics?
     Massimo Giovannini | arXiv, Published in 2007, 179 pages
115. Supernova Cosmology: Legacy and Future
     Ariel Goobar, Bruno Leibundgut | arXiv, Published in 2011, 62 pages
116. Gamma-Ray Bursts: Progress, Problems and Prospects
     Bing Zhang, Peter Meszaros | arXiv, Published in 2008, 87 pages
117. Atlas of Peculiar Galaxies
     Halton C. Arp | California Institute of Technology, Published in 1966, 190 pages
118. High Energy Astrophysics
     Jonathan Katz | The Benjamin/Cummings Publishing, Published in 1986, 338 pages
119. Observing the Sky from 40N
     Roberto Mura | Wikibooks, Published in 2010, 86 pages
120. Advances in Modern Cosmology
     Adnan Ghribi | InTech, Published in 2011, 198 pages
121. First Light
     Abraham Loeb | arXiv, Published in 2006, 157 pages
122. Recreations in Astronomy
     Henry White Warren | Project Gutenberg,
123. Elements of Astrophysics
     Nick Kaiser | University of Hawaii, Published in 2002, 435 pages
124. Celestial Mechanics: Notes and Work
     J.D. Mireles James | Rutgers University, Published in 2007, 128 pages
125. Primer Of Celestial Navigation
     John Favill | Cornell Maritime Press, Published in 1944, 300 pages
126. Mysteries of the Sun
     Ginger Butcher | NASA, Published in 2012, 22 pages
127. Radiative Processes in High Energy Astrophysics
     Gabriele Ghisellini | arXiv, Published in 2012, 157 pages
128. Images of the Solar Upper Atmosphere From SUMER on SOHO
     Uri Feldman, at al. | ESA Publications Division, Published in 2003, 209 pages
129. Astronomical Discovery
     Herbert Hall Turner | E. Arnold, Published in 1904, 225 pages
130. To a Rocky Moon: A Geologist's History of Lunar Exploration
     Don E. Wilhelms | University of Arizona Press, Published in 1993, 524 pages
131. From Disks to Planets
     Andrew N. Youdin, Scott J. Kenyon | arXiv, Published in 2012, 70 pages
132. Space Nomads
     Leota Jean LaPaz, Lincoln LaPaz | Holiday House, Published in 1961, 199 pages
133. Plasma Physics of Extreme Astrophysical Environments
     Dmitri A. Uzdensky, Shane Rightley | arXiv, Published in 2014, 56 pages
134. Dark Energy: Observational Evidence and Theoretical Models
     B. Novosyadlyj, V. Pelykh, Yu. Shtanov, A. Zhuk | Akademperiodyka, Published in 2013, 380 pages
135. Exoplanet Observing for Amateurs
     Bruce L. Gary | Reductionist Publications, Published in 2007, 170 pages
136. Planetary Photometry
     Max Fairbairn | , Published in 2005, 142 pages
137. Gravitational Wave Experiments and Early Universe Cosmology
     Michele Maggiore | arXiv, Published in 2000, 100 pages
138. Introduction to relativistic astrophysics and cosmology through Maple
     V. L. Kalashnikov | arXiv, Published in 2001, 124 pages
139. Introduction to Cosmology
     David H Lyth | arXiv, Published in 1993, 53 pages
140. Archaeology, Anthropology, and Interstellar Communication
     Douglas A. Vakoch | NASA, Published in 2014, 330 pages
141. Cluster Lenses
     Jean-Paul Kneib, Priyamvada Natarajan | arXiv, Published in 2012, 120 pages
142. Everything You Always Wanted To Know About The Cosmological Constant Problem
     Jerome Martin | arXiv, Published in 2012, 89 pages
143. Observatories in Space
     Catherine Turon | arXiv, Published in 2011, 50 pages
144. Origin of the Moon
     W. K. Hartmann, R. J. Phillips, G. J. Taylor | Lunar and Planetary Institute, Published in 1986, 781 pages
145. Solar Neutrinos
     V. Antonelli, L. Miramonti, C. Pena-Garay, A. Serenelli | arXiv, Published in 2012, 51 pages
146. Recent Developments in Gravitational Collapse and Spacetime Singularities
     Pankaj S. Joshi, Daniele Malafarina | arXiv, Published in 2012, 89 pages
147. Great Astronomers
     Robert S. Ball | Isbister, Published in 1895, 392 pages
148. Inflationary Cosmology and Structure Formation
     J. A. Peacock | arXiv, Published in 1996, 77 pages
149. Lecture notes on the formation and early evolution of planetary systems
     Philip J. Armitage | arXiv, Published in 2010, 63 pages
150. Lecture Notes on High Energy Cosmic Rays
     M. Kachelriess | arXiv.org, Published in 2008, 82 pages
151. Pioneer Saturn Encounter
     | NASA, Published in 1979, 45 pages
152. When Biospheres Collide: A History of NASA's Planetary Protection Programs
     Michael Meltzer | NASA, Published in 2011, 542 pages
153. Cosmic Structure, Averaging and Dark Energy
     David L. Wiltshire | arXiv, Published in 2013, 55 pages
154. An Introduction to Quantum Cosmology
     D.L. Wiltshire | arXiv, Published in 2003, 60 pages
155. A Review of the Universe: Structures, Evolutions, Observations, and Theories
     | universe-review.ca, Published in 2009
156. Gravitational Wave Detection by Interferometry
     Matthew Pitkin, Stuart Reid, Sheila Rowan, Jim Hough | arXiv, Published in 2011, 80 pages
157. The Universe in a Helium Droplet
     Grigory E. Volovik | Oxford University Press, Published in 2003, 532 pages
158. Cosmology for Particle Physicists
     U. A. Yajnik | arXiv, Published in 2008, 63 pages
159. Astronomy for Amateurs
     Camille Flammarion | D. Appleton and Company, Published in 1910
160. Observational Probes of Cosmic Acceleration
     David H. Weinberg, et al. | arXiv, Published in 2012, 253 pages
161. An Introduction to Cosmic Rays and Gamma-Ray Bursts
     A. De Rujula | arXiv, Published in 2007, 37 pages
162. Chondrules and their Origins
     Elbert A. King | The Lunar and Planetary Institute, Published in 1983, 377 pages
163. Introduction to Supersymmetry: Astrophysical and Phenomenological Constraints
     Keith A. Olive | arXiv, Published in 1999, 67 pages
164. General Astronomy
     Harold Spencer Jones | Edward Arnold and Company, Published in 1924, 392 pages
165. Cosmology
     V. A. Rubakov | arXiv.org, Published in 2018, 56 pages
166. Practical Astronomy for Engineers
     Frederick Hanley Seares | Stephens, Published in 1909, 160 pages
167. Particle Physics Aspects of Modern Cosmology
     Robert H. Brandenberger | arXiv, Published in 1997, 70 pages
168. Dwarf-Galaxy Cosmology
     Regina Schulte-Ladbeck, at al. | Hindawi Publishing, Published in 2010, 238 pages
169. A Photographic Atlas of Rock Breakdown Features in Geomorphic Environments
     Mary Bourke, Heather Viles | Planetary Science Institute, Published in 2007, 88 pages
170. Habitable Planets for Man
     Stephen H. Dole | RAND Corporation, Published in 1964, 176 pages
171. Lectures on Astronomy, Astrophysics, and Cosmology
     Luis A. Anchordoqui | arXiv, Published in 2007, 41 pages
172. Astronomy
     Andrew Fraknoi, David Morrison, Sidney C. Wolff | Unglue.it, Published in 2016, 1200 pages
173. Astronomical Image and Data Analysis
     J.-L. Starck, F. Murtagh | Springer, Published in 2006, 335 pages
174. Neutrinos and the Stars
     Georg Raffelt | arXiv, Published in 2012, 83 pages
175. Cosmic Microwave Background Anisotropies up to Second Order
     Nicola Bartolo, Sabino Matarrese, Antonio Riotto | arXiv, Published in 2007, 53 pages
176. Mathematical Problems Of Radiative Equilibrium
     Eberhard Hopf | Cambridge University Press, Published in 1934, 123 pages
177. Astronomy with an Opera-glass
     Garrett Putman Serviss | D. Appleton & co., Published in 1890, 154 pages
178. Hours With A Three-Inch Telescope
     William Noble | Longmans, Green & Co., Published in 1887, 159 pages
179. Quantization in Astrophysics, Brownian Motion, and Supersymmetry
     F. Smarandache, V. Christianto | MathTiger, Published in 2007, 516 pages
180. Lunar Stratigraphy and Sedimentology
     John Lindsay | Elsevier, Published in 1976, 311 pages
181. Astronuclear Physics: a Tale of the Atomic Nuclei in the Skies
     M. Arnould, S. Goriely | arXiv.org, Published in 2020, 100 pages
182. The Story of Eclipses
     George F. Chambers | S. S. McClure Co., Published in 1909, 208 pages
183. Telescopic Work for Starlight Evenings
     William F. Denning | Taylor and Francis, Published in 1891, 372 pages
184. Atomic and Molecular Processes in Astronomy and Planetary Science
     Geoffrey A. Blake | California Institute of Technology, Published in 2004
185. On the Origin (and Evolution) of Baryonic Galaxy Halos
     Duncan A. Forbes, Ericson D. Lopez | MDPI AG, Published in 2018, 232 pages
186. The Virial Theorem in Stellar Astrophysics
     George W. Collins, II | Pachart Pub. House, Published in 1978, 135 pages
187. An Introduction into the Theory of Cosmological Structure Formation
     Christian Knobel | arXiv, Published in 2012, 102 pages
188. The Astronomy of the Bible
     E. Walter Maunder | Richard Clay & Sons, Published in 1908
189. Cosmology Primer
     Sean Carroll | preposterousuniverse.com, Published in 2012, 120 pages
190. Superstring Cosmology
     James E. Lidsey, David Wands, E. J. Copeland | arXiv, Published in 2000, 161 pages
191. Ekpyrotic and Cyclic Cosmology
     Jean-Luc Lehners | arXiv, Published in 2009, 79 pages
192. The Formation and Evolution of the Solar System
     James Schombert | University of Oregon, Published in 2007, 233 pages
193. The Complete Idiot's Guide to The Sun
     Jay M. Pasachoff | Alpha, Published in 2003, 350 pages
194. Modified Gravity and Cosmology
     T. Clifton, P.G. Ferreira, A. Padilla, C. Skordis | arXiv, Published in 2012, 312 pages
195. The Foundations of Celestial Mechanics
     George W. Collins, II | Pachart Pub House, Published in 2004, 145 pages
196. Protoplanetary Disks and Their Evolution
     Jonathan P. Williams, Lucas A. Cieza | arXiv, Published in 2011, 65 pages
197. Amateur Telescope Making
     | Springfield Telescope Makers Inc, Published in 2018, 428 pages
198. Chemistry in Protoplanetary Disks
     Thomas Henning, Dmitry Semenov | arXiv, Published in 2013, 84 pages
199. Celestial Navigation, Elementary Astronomy, Piloting
     Arturo Chiesa, Raffaele Chiesa | Sky and Sea Software, Published in 2010
200. Mathematical Theories of Planetary Motions
     Otto Dziobek | The Register Pub. Co., Published in 1892, 314 pages
201. The Telescope
     Louis Bell | McGraw-Hill, Published in 1922, 294 pages
202. Encyclopedia of Astrophysics
     Søren Bertil F. Dorch | Scholarpedia, Published in 2009
203. Mag 7 Star Atlas Project
     Andrew L. Johnson | , Published in 2007, 21 pages
204. Planetary Rings
     Matthew S. Tiscareno | arXiv, Published in 2011, 82 pages
205. Elementary Astronomy
     James N. Pierce | , Published in 2013, 134 pages
206. Vision and Voyages for Planetary Science in the Decade 2013-2022
     | National Academy of Sciences, Published in 2011, 410 pages
207. Evolution of the Solar System
     Hannes Alfven, Gustaf Arrhenius | NASA, Published in 1976, 583 pages
208. Inflation and String Theory
     Daniel Baumann, Liam McAllister | arXiv, Published in 2014, 349 pages
209. The Astrobiology Primer: An Outline of General Knowledge
     Lucas J. Mix, at al. | arXiv, Published in 2006, 79 pages
210. Voyager 1 and 2: Atlas of Six Saturnian Satellites
     Raymond M. Batson | NASA, Published in 1984, 182 pages
211. Applied Cosmography: A Pedagogical Review
     Yu. L. Bolotin, et al. | arXiv.org, Published in 2018, 66 pages
212. A Simple Guide to Backyard Astronomy
     Carol Beigel | , Published in 2008, 61 pages
213. An Exposition on Inflationary Cosmology
     Scott Watson | arXiv, Published in 2000, 93 pages
214. A Guide To The Constellations
     Samuel G. Barton | McGraw-Hill, Published in 1928, 96 pages
215. Cosmology
     James Schombert | University of Oregon, Published in 2008, 123 pages
216. Advances in Global and Local Helioseismology: an Introductory Review
     Alexander G. Kosovichev | arXiv, Published in 2011, 86 pages
217. The Birth and Death of Stars
     James Schombert | University of Oregon, Published in 2008, 324 pages
218. Searching for Life Across Space and Time
     | The National Academies Press, Published in 2017, 133 pages
219. The Elements of Theoretical and Descriptive Astronomy
     Charles J. White | J. Wiley, Published in 1909, 322 pages
220. Astronomy of To-day
     Cecil Goodrich Julius Dolmage | Seeley and co., Published in 1910
221. Moon Trip: A Personal Account of the Apollo Program and its Science
     Elbert A. King | Lunar and Planetary Institute, Published in 1989, 162 pages
222. Notes on Stellar Astrophysics
     James N. Pierce | Minnesota State University, Published in 2013, 299 pages
223. Frequently Asked Questions about Calendars
     Claus Tøndering | , Published in 2008, 65 pages
224. The Star Splitters: The High Energy Astronomy Observatories
     Wallace H. Tucker | NASA History Office, Published in 1984, 182 pages
225. Mercury
     F. Vilas, C. Chapman, M. Matthews | University of Arizona Press, Published in 1989, 794 pages
226. The Galactic Habitable Zone I. Galactic Chemical Evolution
     G. Gonzalez, D. Brownlee, P. Ward | arXiv, Published in 2001, 57 pages
227. Voyage to Jupiter
     David Morrison, Jane Samz | NASA, Published in 1980, 218 pages
228. Cosmology: Mankind's Grand Investigation
     Greg Bothun | Harcourt Brace College Publishers, Published in 1999, 129 pages
229. Celestial Mechanics
     J. B. Tatum | , Published in 2008, 244 pages
230. Galaxies and the Expanding Universe
     James Schombert | University of Oregon, Published in 2008, 146 pages
231. An Introduction to the Theory of Rotating Relativistic Stars
     Eric Gourgoulhon | arXiv, Published in 2010, 88 pages