The basic characteristics of sixty-nine secondary services in physics were analyzed in terms of sponsorship and distribution by: (1) country of origin, (2) language, (3) age, (4) frequency of publication, (5) subject and geographical coverage and (6) size. The eight major services, in terms of size, are identified. The use of the services by the…

The relationship of the mechanics of a falling chimney and a breaking pencil point is presented. A device is discussed that uses a pocket calculator coupled to a telescope to record the angle at which the telescope is pointed. (BB)

Discusses topics related to high-energy, gamma-ray astronomy (including cosmic radiation, gamma-ray detectors, high-energy gamma-ray sources, and others). Also considers motivation for the development of this field, the principal results to date, and future prospects. (JN)

Radio observations show that the gigantic clouds of molecules where stars are born are distributed in various ways in spiral galaxies, perhaps accounting for the variation in their optical appearance. Research studies and findings in this area are reported and discussed. (JN)

This textbook issue has been prepared to accompany later editions, and includes complete reference to all the problems and practical questions contained in Steele's "Popular Physics," "Popular Chemistry," "Hygienic Physiology," and "New Descriptive Astronomy."

The controversial objects, which appear to some to violate the known laws of physics, may prove to be highly condensed, rotating centers of extremely distant galaxies. (Author/DF)

Radioastronomy reveals that clouds between the stars, once believed to consist of simple atoms, contain molecules as complex as seven atoms and may be the most massive objects in our Galaxy. (Author/DF)

This new field, generated from observations above the atmosphere, has been an unexpected gift to astronomy by giving a better understanding of the role and importance of high energy phenomena. The history, instrumentation, and types of celestial sources observed are discussed. (DF)

Recent manned and unmanned space probes have detected hydrogen geocorona and airglow emission bands on the night side of the earth, formed by interplanetary materials. (DF)

The Mariner 9 mission has shown that surface changes, thought previously to be a by-product of some form of life, are intimately connected to strong Martian winds which scour the surface. Close-up photographs of the two moons dispel the notion that they are artificial satellites. (DF)

Objects and energy sources are detected whose existence was only hinted at a few years ago. The X-Ray sky has a large number of sources along the Milky Way, most of which lie within 30 degrees of the galactic center, plus a number of faint sources associated with external galaxies. (DF)

The space shuttle, which will be developed for space transportation in the 1980's, will make space flight simple, less time consuming, and less expensive. (DF)

An experimental space station having three-man crews which will live and work there for periods up to 56 days is designed to provide data needed for long-duration space flight and future spacecraft design. This project will answer many scientific and medical questions. (DF)