4,457 research outputs found

    Economic impact of large public programs: The NASA experience

    Get PDF
    The economic impact of NASA programs on weather forecasting and the computer and semiconductor industries is discussed. Contributions to the advancement of the science of astronomy are also considered

    The Bibliometric Properties of Article Readership Information

    Full text link
    The NASA Astrophysics Data System (ADS), along with astronomy's journals and data centers (a collaboration dubbed URANIA), has developed a distributed on-line digital library which has become the dominant means by which astronomers search, access and read their technical literature. Digital libraries such as the NASA Astrophysics Data System permit the easy accumulation of a new type of bibliometric measure, the number of electronic accesses (``reads'') of individual articles. We explore various aspects of this new measure. We examine the obsolescence function as measured by actual reads, and show that it can be well fit by the sum of four exponentials with very different time constants. We compare the obsolescence function as measured by readership with the obsolescence function as measured by citations. We find that the citation function is proportional to the sum of two of the components of the readership function. This proves that the normative theory of citation is true in the mean. We further examine in detail the similarities and differences between the citation rate, the readership rate and the total citations for individual articles, and discuss some of the causes. Using the number of reads as a bibliometric measure for individuals, we introduce the read-cite diagram to provide a two-dimensional view of an individual's scientific productivity. We develop a simple model to account for an individual's reads and cites and use it to show that the position of a person in the read-cite diagram is a function of age, innate productivity, and work history. We show the age biases of both reads and cites, and develop two new bibliometric measures which have substantially less age bias than citationsComment: ADS bibcode: 2005JASIS..56..111K This is the second paper (the first is Worldwide Use and Impact of the NASA Astrophysics Data System Digital Library) from the original article The NASA Astrophysics Data System: Sociology, Bibliometrics, and Impact, which went on-line in the summer of 200

    Lunar optical telescopes: An historical perspective

    Get PDF
    There is a long history of thought and discussion on the possibilities of astronomical observatories on the Moon. Numerous ideas have been suggested and a variety of concepts have resulted for lunar optical telescopes. This paper reviews some of the ideas and efforts of individuals and working groups including Hershel, Clarke, Malina, Herbig, and Hess; working groups of the 1960s; and recent initiatives of Burke, Burns, and others. The enhanced technologies of the 1980s and 1990s can make past dreams of lunar observatories come to reality in the 21st century

    Space Math IV

    Get PDF
    This booklet includes 31 problems that involve a variety of math skills, including scientific notation, simple algebra, and calculus. Topics covered include black holes, ice on mercury, a mathematical model of the solar interior, sunspots, the heliopause, and coronal mass ejections, among many others. (8.5 x11, 28 pages, 11 color images, PDF file) Educational levels: Intermediate elementary, Middle school, High school

    Aerospace bibliography, fifth edition

    Get PDF
    Bibliography of references, periodicals, and educational materials related to space fligh

    Library Economic Metrics: Examples of the Comparison of Electronic and Print Journal Collections and Collection Services

    Get PDF
    published or submitted for publicatio

    Extragalactic astronomy: The universe beyond our galaxy

    Get PDF
    This single-topic brochure is for high school physical science teachers to use in introducing students to extragalactic astronomy. The material is presented in three parts: the fundamental content of extragalactic astronomy; modern discoveries delineated in greater detail; and a summary of the earlier discussions within the structure of the Big-Bang Theory of evolution. Each of the three sections is followed by student exercises (activities, laboratory projects, and questions-and-answers). The unit close with a glossary which explains unfamilar terms used in the text and a collection of teacher aids (literature references and audiovisual materials for utilization in further study)
    corecore