This Work, undertaken at His Lordship's request, is inscribed as a testimony of the Author's esteem and regard. Although it has unavoidably exceeded the limits of the Publications of the Society for the Diffusion of Useful Knowledge, for which it was originally intended, his Lordship still thinks it may tend to promote the views of the Society in its present form. To concur with that Society in the diffusion of useful knowledge, would be the highest ambition of the Author.

MARY SOMERVILLE

The plans you will find on these pages, are, by and large, the result of years of trial and error on the part of John Dobson, one of the founders of The San Francisco Sidewalk Astronomers and a prolific telescope maker. John has, quite literally, helped thousands of people make telescopes of this design! Only in the past few years have commercial telescope manufacturers adopted the Dobsonian approach to make affordable, alt-azimuth Newtonian telescopes... However, the three top manufacturers (henceforth referred to as: "The Big Three"), Celestron, Meade, and Orion, continue to fall short mechanically of the simple designs found on these pages. All of The Big Three, for example, use Melamine; a kind of coated particle board, which is heavy, not durable, in short; not as strong or light as plywood, which, of course, we recommend. All of The Big Three have undersized pivot bolts, do not use Teflon as bearing surfaces (there is no substitute!), and have shoddy mirror cells (tailgates). The list goes on... They do look "pretty," especially in photos; I'll give them that. If you happen to own one of these scopes; you might well peruse these pages to find ways to tinker and fix up your mass-produced Dob: you can only improve what you got! It ain't rocket science!

Astronomy 161, Introduction to the Solar System, is the first quarter of a 2-quarter introductory Astronomy for non-science majors taught at The Ohio State University. This podcast presents audio recordings of Professor Richard Pogge's lectures from his Autumn Quarter 2006 class. All of the lectures were recorded live in 100 Stillman Hall on the OSU Main Campus in Columbus, Ohio.

The Data Book of Astronomy is a one-stop reference for astronomers at all levels of experience, from beginners to experienced observers. Filled with data about the Earth, Moon, the planets, the stars, our Galaxy, and the myriad galaxies in deep space, it also reveals the latest scientific discoveries about black holes, quasars, and the origins of the Universe. Written by a premier astronomy expert, this book begins with a discussion of the Sun, from sunspots to solar eclipses. It then features over 100 tables on characteristics of the Moon, and the names, positions, sizes, and other key descriptors of all the planets and their satellites. The book tabulates solar and lunar eclipse, comets, close-approach asteroids, and significant meteor showers dates. Twenty-four maps show the surface features of the planets and their moons. The author then looks to the stars, their distances and movements, and their detailed classification and evolution. Forty-eight star charts cover both northern and southern hemispheres, enabling you to track down and name the main stars in all the constellations. The maps are supported by detailed tables of the names, positions, magnitudes, and spectra of the main stars in each constellation, along with key data on galaxies, nebulae, and clusters. There is a useful catalogue of the world's great telescopes and observatories, a history of astronomy and of space research, and biographies of 250 astronomers who have been most influential in developing the current understanding of the subject.

Assuming no prior knowledge of astrophysics or geophysics, this resource focuses on the structure of planets and the stars they orbit and the interactions between them. The book is written in two parts, making it suitable for students at different levels and from differing backgrounds. The first twelve chapters reveal our solar system and the diverse bodies it contains. These are followed by 42 detailed topics that discuss specialized subjects, from stellar formation to exobioloy, in a quantitative manner-essential reading for those in higher level courses. Problems and answers are also included.

No modern astronomer made a more profound contribution to our understanding of the cosmos than did Edwin Hubble, who first conclusively demonstrated that the universe is expanding. Basing his theory on the observation of the change in spectra of distant galaxies, called red shift, Hubble showed that this is a Doppler effect, or alteration in the wavelength of light, resulting from the rapid motion of celestial objects away from Earth.

An important historical look at the space program's evolving telecommunications systems.

Jean Meeus has provided a bridge text for dedicated amateurs interested in astronomical and solar event calculations.

Programming the calculations provided by Meeus is possible using any modern programming language. Meeus covers a wide range of astronomical areas.

The book is designed as an astrophysics textbook that provides a comprehensive introduction to the physics of Interstellar Matter. It is aimed primarily at those undertaking postgraduate courses, or those doing advanced projects as part of honors undergraduate courses in physics or astrophysics. It should also provide a handy reference to the field for astrophysics faculty and other researchers who are not necessarily experts in this particular subdiscipline. The objective of Astrophysics of the Diffuse Universe is to show how physics can be applied to the understanding and diagnosis of the phase structure, the physical conditions, and the chemical make-up and evolution of the interstellar medium. Consistent with the authors' lecture and course experience, here a systematic approach has been adopted to assist the development of the reader's insight into the physics underlying the subject.