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[en] An historical account is given of major, telescopic instrument-related advancements in 20th-century astronomy, with attention to the roles played by leading figures in the various fields of astronomical research involved. These biographical treatments encompass David Heeshen and the development of the VLA; Riccardo Giacconi and the X-ray astronomy Uhuru, High Energy Astronomy Observatory, and X-ray Explorer, and Einstein Observatory satellites; Allan Jacobson and the Gamma Ray Observatory satellite; the involvements of Frank Low and Gerry Neugebauer in the development of the IR Astronomy Satellite; and C. R. O'Dell's organization of the NASA Space Telescope program. 62 references
[en] Topics covered the setting; looking at the stars; the earth; time, place and the sky; our satellite, the moon; orbits and motion; the motions of the planets; the Copernican revolution; the planets; the other bodies of the solar system; ages, origins, and life; introducing the stars; sorting out the stars; binary stars--two are better than one; variable stars--inconstancy as a virtue; the secrets of starlight--unraveling the spectrum; the sun--our own star; the structure of a star; interstellar material; the Milky Way, our home galaxy; galaxies--the stellar continents; cosmic violence--from radio galaxies to quasars; the universe; and epilogue. The primary emphasis is on how we have come to know what we know about the universe. Star maps are included
[en] Uhuru, the first X-ray astronomy satellite, was launched in 1970. Its instruments performed the first all sky survey in X-rays. Approximately half of the 400 sources discovered by Uhuru and its successor Ariel-5 are galactic objects: binary systems containing neutron stars and possibly blackholes, X-ray bursters, supernova remnants and transients. The extragalactic sources are mainly clusters of galaxies as well as Seyfert galaxies and BL Lac Objects. The identifications and follow-up studies of these sources have produced the main advances in X-ray astronomy in the first half of the 1970's. The follow-up surveys with the A-1, A-2 and A-4 instruments on HEAO-1, provided an increase in spectral coverage and somewhat higher sensitivities. The A-1 experiment detected more than 800 sources with fluxes 0.5 mCrab in the 1-25 keV band. In view of the limited positional resolution of the collimated detectors used in these missions, identifications have been a problem. In this context the rotation modulation collimators flown on SAS-3 and HEAO-1 (A-3 experiment) have played a major role. In this paper the author concentrates on some scientific and technical aspects of the X-ray sky survey. ROSAT is a German satellite with substantial US and UK (XUV wide field camera) contributions. The ROSAT X-ray optics consist of a fourfold nested mirror system of Wolter type I with 83 cm aperture having an intrinsic resolution of a few arcseconds. The focal plane assembly comprises two position sensitive proportional counters (PSPC) and one high resolution imager (HRI), which are mounted on a carousel. This paper also shows a cross section of the X-ray telescope
[en] The capability of registration of the primary high energy cosmic ray gamma emission by a gamma-telescope made of an image calorimeter is shown in this paper. The problem of triggering and off-line identification of primary particles by the analysis of the electromagnetic showers induced in the calorimeter is under consideration. The estimations of the background flux of delayed secondaries induced by nuclear interactions are presented too
[en] The proposal for an experiment on the International Space Station that will perform an all sky survey of the soft X-ray background for interstellar and intergalactic medium studies has been submitted to the Italian Space Agency (ASI). The goal of the experiment is to obtain spectroscopic information on the X-ray diffuse background in the energy range 30-1000 eV. This information will address many questions concerning the origin, composition, structure and evolution of the interstellar and intergalactic medium. The experiment will be installed on one of the outside mounting pallets of the Space Station looking at the local zenith with a field of view of 10 deg.
[en] Until recently little more was known than that dark matter appears to exist; there was little systematic information about its properties. Only in the past several years was progress made to the point where dark matter density distributions can be measured. For example, with accurate rotation curves extending over large ranges in radius, decomposing the effects of visible and dark matter to measure dark matter density profiles can be tried. Some regularities in dark matter behaviour have already turned up. This volume includes review and invited papers, poster papers, and the two general discussions. (Auth.)
[en] This paper presents the non-homogeneous Poisson process (NHPP) for modeling the rate of fast radio bursts (FRBs) and other infrequently observed astronomical events. The NHPP, well-known in statistics, can model dependence of the rate on both astronomical features and the details of an observing campaign. This is particularly helpful for rare events like FRBs because the NHPP can combine information across surveys, making the most of all available information. The goal of the paper is two-fold. First, it is intended to be a tutorial on the use of the NHPP. Second, we build an NHPP model that incorporates beam patterns and a power law flux distribution for the rate of FRBs. Using information from 12 surveys including 15 detections, we find an all-sky FRB rate of 587 events per sky per day above a flux of 1 Jy (95% CI: 272, 924) and a flux power-law index of 0:91 (95% CI: 0.57, 1.25).
[en] The nuclear gamma astronomy is presented, in particular the Gamma Ray Observatory, an enormous eight tonnes machine fitted with gamma telescopes, scheduled for launching around 1985. It is thereby hoped to study the natural nuclear reactions which occur when stars explode
[fr]On presente l'astronomie gamma nucleaire, et en particulier le Gamma Ray Observatory, un enorme engin de 8 tonnes equipe de telescopes gamma qui devrait etre lance vers 1985. On espere ainsi etudier les reactions nucleaires naturelles qui se produisent au cours de l'explosion des etoiles