Astronomy. Gamma-ray astronomy with INTEGRAL.
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Astronomy thrived in Europe during the early nineteenth century, but in the United States a utilitarian mind-set opposed it. John Quincy Adams's oratory in support of American astronomical discovery reached its peak during congressional debate over the Smithsonian Institution (1838-1846). During this debate Adams countered proposals to found a university with plans for an observatory. His addresses to congressional and public audiences about observatories and astronomy were intended to foster interest in the science and encourage the growing astronomical community in America. Although the U.S. Naval Observatory in Washington, D.C., was established before the Smithsonian debate ended, many considered Adams its political father. Adams composed his speeches on astronomy in a systematic manner, following neoclassical principles of rhetoric that he had taught at Harvard University. His speeches both in and outside of Congress show evidence of the rhetorical principles he conscientiously used in the service of astronomy.
Fresnel lenses allow almost perfect imaging in widely different circumstances, but their focus is perfect only for a single wavelength. Wang et al. have shown how the effective bandpass may be widened for X-ray microscopy by using a compound diffractive/refractive lens near to an absorption edge. A compound lens has also been proposed for high-energy astronomy, working well above all absorption edges. Although the scale is very different, we point out here that the principle is the same. Ever since Galileo constructed an astronomical telescope that he was able to reconfigure to study fleas and gnats, astronomy and microscopy have relied on optics that are closely related, but different in detail.
Astronomical techniques, calendars and devices were developed independently in many places around the world. However, there was much cross-cultural exchange of technology over the centuries. The cultures of Egypt, Greece, India and China influenced each others' astronomy and each cannot be treated in isolation.
The extreme ultraviolet wave band (100 to 912 angstroms) was thought until recently to be useless to astronomy, primarily because the opacity of the interstellar medium would prevent observations at these wavelengths. However, the interstellar medium has been found to be markedly inhomogeneous in both density and ionization state and the sun is fortunately located in a region of low extreme ultraviolet opacity. The Extreme Ultraviolet Explorer, launched in June 1992, has surveyed the sky in this wave band and has detected a wide variety of astronomical sources at considerable distances, including some extragalactic objects. Studies in the extreme ultraviolet band have already begun to increase our understanding of the contents of the universe.
STUDY OBJECTIVES: Assess the potential health impacts of the proposed International Astronomy and Space Exploration Centre on the population of New Wallasey. Contribute to the piloting of health impact assessment methods. DESIGN: Prospective health impact assessment involving brainstorming sessions and individual interviews with key informants and a literature review. SETTING: New Wallasey Single Regeneration Budget 4 area. PARTICIPANTS: Key stakeholders including local residents' groups selected through purposeful snowball sampling. MAIN RESULTS: Recommendations are made that cover issues around: transport and traffic; civic design; security; public safety, employment and training. CONCLUSIONS: Health impact assessment is a useful pragmatic tool for facilitating wide consultation. In particular engaging the local population in the early planning stages of a proposed development, and assisting in highlighting changes to maximise the positive health influences on affected communities.
Recent X-ray observations have had a major impact on topics ranging from proto-stars to cosmology. They have also drawn attention to important and general physical processes that currently limit our understanding of thermal and non-thermal X-ray sources. These include unmeasured atomic astrophysics data (wavelengths, oscillator strengths, etc.), basic hydromagnetic processes (e.g. shock structure, reconnection), plasma processes (such as electron-ion equipartition and heat conduction) and radiative transfer (in discs and accretion columns). Progress on these problems will probably come from integrative studies that draw upon observations, throughout the electromagnetic spectrum, of different classes of source. X-ray observations are also giving a new perspective on astronomical subjects, like the nature of galactic nuclei and the evolution of stellar populations. In addition, they are helping us to address central cosmological questions, including the measurement of the matter content of the Universe, understanding its overall luminosity density, describing its chemical evolution and locating the first luminous objects. X-ray astronomy has a healthy future with several international space missions under construction and in development.
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The pure carbon molecules Cn are currently of great experimental and theoretical interest. Our work in this area begins with detection of the SiC molecule, which is isovalent with C2. New infrared electronic transitions of C2 and C3 were discovered by emission spectroscopy of hydrocarbon dicharges. The C3 and C5 molecules were found by infrared vibration-rotation spectroscopy of the prototypical obscured carbon star, IRC+10216. C7 and C9 were searched for in the same source, but not found. The laboratory infrared emission spectrum of C60 was recorded to aid in a search for C60 in extraterrestrial sources.
In the last decade, the use of neural networks (NN) and of other soft computing methods has begun to spread also in the astronomical community which, due to the required accuracy of the measurements, is usually reluctant to use automatic tools to perform even the most common tasks of data reduction and data mining. The federation of heterogeneous large astronomical databases which is foreseen in the framework of the astrophysical virtual observatory and national virtual observatory projects, is, however, posing unprecedented data mining and visualization problems which will find a rather natural and user friendly answer in artificial intelligence tools based on NNs, fuzzy sets or genetic algorithms. This review is aimed to both astronomers (who often have little knowledge of the methodological background) and computer scientists (who often know little about potentially interesting applications), and therefore will be structured as follows: after giving a short introduction to the subject, we shall summarize the methodological background and focus our attention on some of the most interesting fields of application, namely: object extraction and classification, time series analysis, noise identification, and data mining. Most of the original work described in the paper has been performed in the framework of the AstroNeural collaboration (Napoli-Salerno).
After 1700, astrology lost the respect it once commanded in medical circles. But the belief that the heavens influenced bodily health persisted - even in learned medicine - until well into the nineteenth century. The continuing vitality of these ideas owed much to the new empirical and mechanical outlook of their proponents. Taking their cue from the work of Robert Boyle and Richard Mead, a number of British practitioners amassed statistical evidence which purported to prove the influence of the Moon upon fevers and other diseases. Such ideas flourished in the colonies and in the medical services of the armed forces, but their exponents were not marginal men. Some, like James Lind, were widely respected and drew support for their views from such influential figures as Erasmus Darwin.
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