The Journal of Astronomical Data 2003, Volume 9 ABSTRACTS =============================================================== [JAD 9, 1] The Muenster Red Sky Survey: Large Scale Structures in the Universe R. Ungruhe We present a large-scale galaxy catalogue for the red spectral region which covers an area of 5\,000 square degrees. It contains positions, red magnitudes, radii, ellipticities and position angles of about 5.5 million galaxies. Together with the APM catalogue (4,300 square degrees) in the blue spectral region, this catalogue forms at present the largest coherent data base for cosmological investigations in the southern hemisphere. 217 ESO Southern Sky Atlas R Schmidt plates with galactic latitudes -45 degrees were digitized with the two PDS microdensitometers of the Astronomisches Institut Münster, with a step width of 15 microns, corresponding to 1.01 arcseconds per pixel. All data were stored on different storage media and are available for further investigations. Suitable search parameters must be chosen in such a way that all objects are found on the plates, and that the percentage of artificial objects remains as low as possible. Based on two reference areas on different plates, a search threshold of 140 PDS density units and a minimum number of four pixels per object were chosen. The detected objects were stored, according to size, in frames of different size length. Each object was investigated in its frame, and 18 object parameters were determined. The classification of objects into stars, galaxies and perturbed objects was done with an automatic procedure which makes use of combinations of computed object parameters. In the first step, the perturbed objects are removed from the catalogue. Double objects and noise objects can be excluded on the basis of symmetry properties, while for satellite trails, a new classification criterium based on apparent magnitude, effective radius and apparent ellipticity, was developed. For the remaining objects, a star/galaxy separation was carried out. For bright objects, the relation between apparent magnitude and effective radius serves as the discriminating property, for fainter objects, the relation between effective radius and central intensity was used. In addition, a few regions of enhanced object density like dwarf galaxies and star clusters were removed from the catalogue. Because error estimates of the automatic classificationprocedure are very uncertain, an extensive visual check of the automatic classification was carried out. A large number of objects previously classified automatically - 1.3 million galaxies, 815,000 stars and 647,000 perturbed objects - was re-classified by eye. We found that galaxies suffer most from misclassification. Down to magnitude 13, the error is, independent of galactic latitude, at least 60%. Between13th and 17th magnitude, the percentage of misclassified galaxies for b < -45 degrees drops continuously to between 15% and 30%, and is clearly dependent on galactic latitude. The classification of galaxies at low galactic latitudes is most strongly affected; in these regions only half of the galaxies are correctly classified. Errors found in this work thus lie by a factor 2-3 above values quoted in the literature.Stars show classification errors of at most 10%, whose level increases towards fainter magnitudes. The classification accuracy is less dependent on galactic latitude than in the case of galaxies. As concerns artifacts, noticeable classification errors occur only for objects brighter than magnitude 15, which is mainly caused by saturation effects of the photographic emulsion. At magnitudes fainter than 15th,the error is below 5%. No dependence from galactic latitude is seen. These investigations show that the automatic classification yields satisfactory results only in certain magnitude intervals, which depend on galactic latitude. The object magnitudes are influenced by the desensitization of the emulsion during exposure and by the vignetting of the telescope. Objects at the plate margins appear systematically too faint. The magnitudes were corrected by means of measured number densities of galaxies and stars, which were determined in 63 fields around the galactic southpole. The difference of the magnitude zero-point between the center and the margin of a plate amounts to approximately 0.05 mag after correction of the margin desensitization. Because of their high central intensity, stars reach the saturation limit of the emulsion already at magnitude 17. Thus bright stars appear systematically too faint. The saturation effect can be corrected by means of a point-spread function, which is calculated from the unsaturated parts of the stellar intensity profiles. The magnitude corrections for the saturation are carried out for each plate separately. In order to establish a unique magnitude zero-point for the 217 single plates, a mutual adjustment of neighbouring fields by means of their overlap regions was done. The procedure was carried out separately for stars and galaxies. In total, 1,005 overlap regions for galaxies and 1,103 regions for stars were available. The zero-point error after adjustment amounts to 0.06 mag for galaxies and 0.07 mag for stars. The external calibration of the photographic rF magnitudes was carried out by means of CCD sequences obtained with three telescopes in Chile and South Africa. In total, photometric V, R data for 1,037 galaxies and 1,058 stars in 92 fields are available. The transformation between photographic and CCD magnitudes requires a relation between F and VR.It was carried out separately for stars and galaxies, because they show different colour transformations. After the transformation of the photographic rF magnitudes to the standard Johnson R system, the errors of the local magnitude zero-point amount to 0.11 mag. for galaxies and 0.15 mag for stars. Because of the large areal extent of the catalogue, the galaxy magnitudes must be corrected for interstellar extinction. Magnitude corrections are based on hydrogen column densitiesof interstellar dust. Extinction corrections amount to up to0.1 mag for 55% of galaxies, and 0.2 mag for another 35%. For the remaining 10%, the corrections are above 0.2 mag.The iteration procedure for the indirect adjustment of single platesmay cause a magnitude gradient in north-south or east-west direction. Investigations of the magnitude differences between photographic and CCD magnitudes versus right ascension and declination show no significant gradients.In order to generate a complete catalogue of galaxies and stars, all double or multiple objects that occur in overlap regions have to be excluded. After the merging of all single plates (including half of the overlap regions), both catalogues contain 5.5 million galaxies and 20.2 million stars. The completeness of the catalogues was investigated from the comparison of counts of stars and galaxies with simulations. The limit of completenessis at magnitude18.3 for galaxies, and at 18.8 for stars. In the case of galaxies, a clear deficit is seen for galaxies down to magitude 16 in comparison with the simulation. Neither by taking into account galaxy evolution, nor by changes in the cosmological parameters, an adjustment of the simulation to the catalogue counts was possible. These results and those of others support the assumption that we are dealing with a real galaxy deficit. The determined slope of 0.66 of the galaxy counts is, within the limits of accuracy, in agreement with the measured values of other authors. No comparable star counts are available. The N-point angular correlation function were determined from various sub-catalogues consisting of 9, 25, 63, 121 and 152 fields as well asfor limiting magnitudes from magnitudes 15.0 to 19.0. The computation of chance distributions was carried out for galaxy counts in cells with side borders from 25''to 28.4''. Averaged correlation functions and their coefficients were determined by means of factorial moments. The delete-d jackknife procedure was applied for the error estimate, with 200 replications per subcatalogue. The 2-point angular correlation function shows a linear trend in logarithmic plots for all sub-catalogues on scales from 0.02 to 2degrees.Within this range, it can be parametrized by a power law omega2 = A theta exp(1-gamma). Depending on sub-catalogue, the gamma values scatter between 1.63 and 1.73. They show a good agreement with the EDSGC, APM and MRSP catalogues. The parametrization of the amplitudeof the 2-point angular correlation versus apparent magnitude yields beta values between 0.267 and 0.322, which are in accordance with beta values from model calculations. The curve form of the 2-point angularcorrelation function shows a significantly flatter decline on scales exceeding 2 degrees which cannot be reproduced by the standard CDM-model. The correlation functions of higher order intersect at a point theta_S, whose position depends on the limiting magnitude. For scales theta theta_S,they decay very quickly. Since the higher orders only occur in galaxyclusters, the intersection can be taken as a measure for the cluster size.Correlations for the third to fifth order that still exist on large scalesindicate that, compared to the size of galaxy clusters, larger structuresexist, the superclusters. The correlation function coefficients with N larger or equal to 3 show characteristicplateaus for all limiting magnitudes, whose length depends on the order considered. Simulations have shown that the plateaus ofsmall scales point towards a strong non-linear cluster formation. The meaning of plateaus on large scales is not yet known. Comparisons with the APM- and MRSP-catalogues show a good agreement, both in the shape as well asin the amplitudes of the coefficients. Only the EDSGC shows significantly higher amplitudes on small scales, which are likely caused by wronglyclassified and/or doubly counted galaxies. This paper is an edited and translated version of a Ph.D. thesis, submitted by R. Ungruhe to Muenster University in 1998. It is released to make the results from this work available to a larger scientific community. Since the data of the galaxy catalogue will also be made available through the NED/IPAC database, its users can make themselves familiar with the methods of analysis and of the construction of the catalogue. Another paper, "Angular and three-dimensional correlation functions determined from the Muenster Red Sky Survey" by P. Boschan (the second referee of the Ph.D. thesis), published in Monthly Notices of the Royal Astronomical Society, Vol. 334, pp. 297-309, is to a very large part based on the contents of the thesis. It should be noted that it was written without the knowledge and without the permission of the author of the Ph.D. thesis. ---------------------------------------------------------------------------------------------------- [JAD 9, 2] UBV photometry of 56 Ari: 1990-1994 R. E. Fried and S. J. Adelman We report on five seasons of UBV photometry of 56 Ari obtained with the 0.4-m telescope of the Braeside Observatory starting in the fall of 1990. These observations were part of the data used by Adelman et al. (2001) to find the very slow decrease in the main period of this magnetic CP star and the secondary period of approximately 5 years. Comparison of the light curves obtained in different seasons even with the same telescope tend to show slight discrepancies. ---------------------------------------------------------------------------------------------------- [JAD 9, 3] The CTIO nova survey: data R.E. Williams, M. Hamuy, M.M. Phillips, S.R. Heathcote, L. Wells, M. Navarrete, and H.W. Duerbeck We present 198 optical postoutburst spectra in digital form for 27 novae (23 classical, 4 recurrent). Broad wavelength coverage (between 320 and 1600 nm) has been emphasized at the expense of spectral resolution although the latter has been sufficient to resolve the emission lines. For many of the novae, the temporal coverage has been adequate to document the progressive evolution of the emisison line spectra from the earliest stages at maximum light, dominated by premitted transitions, to the later stages when nebular forbidden lines predominate. Brief descriptions of the spectral evolution for each object are given, and light curves are displayed. ---------------------------------------------------------------------------------------------------- [JAD 9, 4] The CommandLog: A comprehensive method to extract precise stellar photometry from CCD exposures R. Janusz and R. P. Boyle The CommandLog contains a comprehensive method for extracting precise stellar photometry from CCD frames. It has been prepared mainly for the Vatican Advanced Technology Telescope data frames. An IRAF package of tasks (CL and PERL scripts) is given and some easy to process data frames included as an example. The use of text tables allows organizing the frames and preparing them for automatic processing. The CommandLog contains an HTML document which facilitates following carefully detailed instructions and examining data frames. Pasting source CL code from an HTML window to the IRAF CL allows estimating and controlling all necessary IRAF parameters. Adaptation to other data sets should be easy enough provided one adheres to software conventions of IRAF, TTABLES, and PERL. ---------------------------------------------------------------------------------------------------- [JAD 9, 5] BOOK REVIEW: Beitraege zur Astronomiegeschichte, Band 5 (Acta Historica Astronomiae Vol. 16) Wolfgang R. Dick & Juergen Hamel, eds. (Reviewed by H.W. Duerbeck) The 18th volume of the Acta Historica Astronomiae is at the same time the sixth collection of essays on the history of astronomy ("Beiträge zur Astronomiegeschichte, Band 6"), edited by the historians of astronomy W.R. Dick (Potsdam) and J. Hamel (Berlin). Besides a few short notices and book reviews, the book contains eight major articles, which deal with astronomical topics covering the time from the 16th to the 19th centuries. The first article by Michael Weichenhan (Berlin) deals with "the invention of the disk-shaped earth: a chapter of Copernican apologetics". The author shows that the concept of a "disc-shaped Earth" was by no means widespread in the middle ages, but restricted to the father of the church Lactantius and some adherents. Nevertheless, it was used by adherents of Copernicus to show the absurd consequences of a strictly literal biblical interpretation -- here concerning the Earth's shape, disc versus sphere, there the geocentric versus the heliocentric system. This thorough philosophical study is followed by two very short articles. "The measuring accuracy of Tycho's large sextant" by Johann Wünsch investigates O-C values of planet-star distances, as based on Tycho's observations as published in the Historia Coelestis (a compilation, which is also based on Tycho's manuscripts, and published in Regensburg in 1672). The result is that standard deviations are 80 arcseconds for Saturn and 89 arcseconds for Jupiter and Mars, an unexpectedly poor result in view of the general opinion that Tycho was famous for his precision work. "The astronomer Christoph Grienberger and the Galilei trial" by Franz Daxecker deals with a Jesuit astronomer who was both the disciple and successor of the mathematician-astronomer Christopher Clavius at the Collegium Romanum. While he was inclined to Galilei early on, he was forced to propagate Aristotelian doctrine. The brief article is very concise, but extremely tiresome to read (3 pages of pure text are embellished by 33 footnotes). The 3-page paper on Grienberger is followed by a 50-page paper on Kordenbusch. Hans Gaab presents a thoroughly researched biography of the Nuremberg astronomer Georg Friedrich Kordenbusch (1731-1802). Educated as a doctor of medicine, he nevertheless became teacher of mathematics and physics at the Egidien gymnasium, attempted to revitalize the Nuremberg Observatory, and issued a second edition of Johann Leonard Rost's Astronomisches Handbuch (1718), the first compendium of astronomy written in German. He also edited and translated some French works (star maps, a description of globes, and an elementary book on cosmography). Dietmar Fürst (Berlin), who has already published in this series three articles on the foundation of Königsberg Observatory, now presents the first part of the history of the Königsberg heliometer, an instrument which is famous since it was used by Bessel to determine the trigonometric parallax of 61 Cygni. Fürst informs us about the purchase and the putting in operation of the instrument, which was endangered by Fraunhofer's death and delayed by (unavoidably counterproductive?) administrative activities. Reinhold Haefner, astronomer at Munich Observatory, and Rolf Riekher, optician in Berlin, have joined forces to present some pioneers of stellar spectroscopy in "the astro-spectroscopic researches by Fraunhofer and Lamont". It is well known that Fraunhofer observed the solar spectrum with high enough resolution to detect the Fraunhofer lines, but it is less known that he also observed bright planets and fixed stars at the Munich Observatiory, with the assistance of its director Soldner. A publication of 1823 gives only a short summary of this stellar work, and Fraunhofer's early death, three years later, was possibly the cause that no detailed article ever appeared. Interestingly, the second director of the observatory, Johann von Lamont, used the new large refractor (aperture: 28 cm, focal length about 5 m) to observe stellar spectra in 1836. The authors quote details from the observing book and present some sketches (whose reproduction is somewhat poor, and the reader is referred to Häfner's history of Munich Observatory, discussed elsewhere in this volume of JAD, to see a better colour reproduction of a spectral sketch of Lamont). The impact of these studies (or rather the lack of it) is also briefly reviewed. Manfred Strumpf (Gotha) describes the difficulties in finding suitable directors for the Gotha Observatory - when the funds became smaller and the post thus became less and less attractive. Only the wealthy Nikolaus von Konkoly, a serious amateur and pioneer of astrophysics, applied even twice, but the administration was reluctant to seriously consider his offer. The result was that the chosen candidates were mainstream astronomers who used Gotha only as a step to foster their career and to find a better position as soon as possible. Finally, Peter Brosche (Daun) and Endre Zsoldos (Budapest) trace the life of a hitherto elusive craftsman-scientist, Friedrich Schwab. He was chosen to be the mechanic of one of the Venus transit expeditions of the German Empire (1882 to Punta Arenas), became university mechanic in Klausenburg, and later teacher at the technical school in Ilmenau. He was an active observer of variable stars and also a specialist in endomological studies. The authors have located a grand-son and have put to light some valuable notes and photographs. As can be seen from the summaries given above, this collection of essays deals mainly with historical events that occurred in Germany and neighboring countries, and focuses mainly on events in the 17th to 19th centuries. All contributions are written in German. The editors have taken care that generally a high standard was kept, although topic and realization make some articles more pleasant to read than others. ---------------------------------------------------------------------------------------------------- [JAD 9, 6] BOOK REVIEW: Die Universitäts-Sternwarte München im Wandel ihrer Geschichte Reinhold Haefner (Reviewed by H.W. Duerbeck) This concise history of Munich Observatory, written by a staff member, is actually the second, enlarged and updated edition of a brochure that was based on a pair of articles in the now defunct journal Die Sterne (Vol. 68, 263 and 340, 1992). First attempts to establish an observatory in Munich date back to 1759, when the Bavarian Academy of Sciences was founded and a topographic survey was begun; but these private attempts did not lead to a permanent installation. A more official interest arose when a topographic bureau was opened under French direction in 1801, and when the prince-elect Max IV Joseph planned a new land tax which required precise mapping. The collapse of the French rule also meant a collapse of the plans for the new observatory. In 1816, however, things began to develop with an unprecedented speed. The astronomer and surveyor Johann Georg von Soldner was appointed to become observatory director, and king Max I Joseph gave the order to erect the new observatory, which was completed near the end of 1817. The location was chosen near the the village of Bogenhausen (now a suburb of Munich). It took a little longer to install the instrumentation; first observations started in early 1819. Soldner's circle of friends comprised local instrument makers, including Fraunhofer and Reichenbach. With the former, he completed a new apparatus for experiments on the nature of the light of the fixed stars, a refractor of 10 cm aperture equipped with an objective prism. The study of sunlight, began by Fraunhofer, was now extended to the light of planets and fixed stars. Soldner also started a continuous meteorological record. But his name will always be remembered in the annals of science because of a short note, published in 1801 when he was still a student of Bode in Berlin, his On the deviation of a light ray from its rectilinear motion by the attraction of a celestial body which it passes at short distance. Soldner's last years were darkened by illness and enmities. Unfortunately the book does not tell anything about the notorious lunar observer Franz von Paula Gruithuisen, who was appointed professor of astronomy at Munich University in 1826. Soldner died in 1833, and his position was taken by Johann von Lamont, who did pioneering astrometric measurements of Halley's comet, took up again Fraunhofer's and Soldners studies of stellar spectra, but then felt that he should concentrate on only a few studies (stellar positions, magnetic and meteorological measurements). In addition he installed a mechanical workshop in the observatory, where many of the instruments were built, and which exists till the present day. After his death, a three-year vacancy of the director's chair was filled by the mathematician Ludwig Seidel. This was followed by the long reign of Hugo von Seeliger, beginning in 1882 and only ending in 1924. He is most famous for his studies in stellar statistics and other theoretical fields, but he was also active in observational work, including the timeservice. The following 25 years saw two less known directors, Alexander Wilkens and Wilhelm Rabe. After the latter's dismissal, Erich Schoenberg, a theoretician from Breslau, took over in 1949. Numerous changes had happened since Seeliger's time: the integration of a private solar observatory in Herrsching in 1932, which was dissolved in 1946, the transformation into a ``University Observatory'' in 1937/8, major damages through air raids in 1944, and finally, in 1949, the integration of the Wendelstein Solar Observatory, founded by the Deutsche Versuchsanstalt für Luftfahrt in 1941, as one of a series of stations to monitor solar activity. Schoenberg's retirement in 1955 was followed by an interim time of six years. In the following 21 years, Peter Wellmann re-shaped the observatory by building a research group on stellar atmospheres, one of the fields in which the observatory still excels. In the era of Rolf Kudritzki (1982 - 1998), these studies were further pursued and extended. An overview of the Observatory's actual research fields, research installations, its development of modern instrumentation, as well as its activities in public outreach (dating back to TV programmes by R. Kühn in the 1950s which the reviewer still vividly recalls) conclude this historic overview. The appendix lists the Observatory's publication series, statistics of recent publications and their impact, as well as post statistics of the institute - the booklet may also have been written to serve as a lobbying tool for governmental and private sponsorship. Häfner has succeeded in writing a concise sketch of the history of a an important German astronomical institution. It contains a lot of citations from original sources, printed in italics (without indicating their exact locations - this is understandable since Häfner did not want to write an ``academic'' article full of references and footnotes), as well as a useful bibliography. ---------------------------------------------------------------------------------------------------- [JAD 9, 7] BOOK REVIEW: Tycho Brahe and Prague: Crossroads of European Science J.R. Christianson, A. Hadravova, P. Hadrava and M. Solc (Reviewed by C. Sterken) The 16th volume of the Acta Historica Astronomiae is the Proceedings of the International Symposium on the History of Science in the Rudolphine Period. The meeting was held in Prague from 22 to 25 October 2001, on the 400th anniversary of Tycho's sudden death, and was attended by approximately 65 scientists and historians. The volume contains 36 contributions dealing with the life and work of Tycho Brahe, the astronomy of the era, and many cultural aspects of Rudolphine Prague. One of the first papers is an eye-opener on the fact that Tycho Brahe was a cosmologically-driven observer. This is followed by a very illuminating paper on gender roles in science in the late 16th century, with emphasis on the role of Sophie Brahe, Tycho's youngest sister. Several subsequent papers reveal the existence of barely known links between Tycho and his contemporaneous colleagues. These extremely-well documented papers also deal with the broader philosophical investigation he was involved in, viz. meteorology, medicine, astrology, alchemy and even theology. Important names of Tycho's days are Petrus Severinus, Johannes Pratensis, Theophrastus Paracelsus, John Craig, Ursus (Nicolai Reymers Baer) etc. Very illuminating is the information on the relations between Tycho and the Jesuits in Prague, explaining the reason why this order was very supportive of the Tychonic cosmological model. The relationsship with Kepler, and also Kepler's observational activities (after Tycho's death) are highlighted as well as the hideous mode of communication between Galileo and Kepler. More than one paper deals with the accuracy and precision of Tycho's observations, and the causal impact of this accuracy on the scientific revolution. Another study discusses the study of Tycho's handwriting, this paper brings the aditional bonus of a list of accessible works which contain notes by him. One very interesting project was Brahe's proposal to the Republic of Venice to determine the exact latitudes of geographical points at different epochs in order to prove that the value of the precession is constant, which would support his cosmological model. Technically, the book has several regrettable shortcomings: there is no subject nor object index, the layout is rather heterogeneous (some papers have figure captions and others not, only 7 papers have a list of references at the end, some papers are structured in Sections but several are not). Most references appear in footnotes, and several of these footnotes cover a full page or even more, a truly irritating situation for the reader. About 10% of the papers are written in German, the remaining are in English. Despite the editorial imperfections, this is a delightful book, a treasure trove of detailed information which usually is not available in textbooks on the history of astronomy. It is one of these rare proceedings that makes the reader truly regret the fact that he or she could not participate at the conference. This is great informative value for the money. ---------------------------------------------------------------------------------------------------- [JAD 9, 8] GAIA and DIVA Photometry: Towards the Fine Structure of the HR Diagram? T. Lejeune, J. Fernandes and E. Lastennet (Eds.) [JAD 9, 8A] Spectrophotometric information from the DIVA satellite K.S. de Boer, P.G. Willemsen, K. Reif, H. Poschmann, K.-H. Marien, T.A. Kaempf, M. Hilker, D.W. Evans, C.A.L. Bailer-Jones The DIVA satellite will, in addition to the astrometry, obtain photometric data for about 40 million survey stars and spectral data for about a third of these. Relevant sections of the CCD-data stream will be transmitted to Earth to allow a photometric and a spectrophotometric analysis. The DIVA photometric (SM) data can be used to derive stellar colours. Colours are in particular required for the chromaticity correction of the astrometry. The UV telescope (UV) is designed to obtain information about the Balmer jump region of the spectral energy distribution. The spectrophotometric (SC) data consists of overlapping spectral orders in the cross-scan direction. From these SC images the dispi (dispersed position-coded intensity) will be derived. The information on all stellar parameters is, of course, contained in the dispi and can be extracted without deconvolution. CCDs of the type foreseen for DIVA are in the process of being tested for their performance under the special conditions of this space mission. Methods are being tested, like artificial neural networks (ANNs) and others, to derive the astrophysical parameters Teff, log g, [M/H], and E(B-V) from the dispi. We find that even with the relatively modest spectral resolution of the dispi the ANN can discriminate well in temperature, moderately well in gravity and extinction, and crudely in metallicity, all clearly dependent on the brightness of the star. Degeneracy in the temperature and extinction determination can be lifted especially using Balmer jump information from the DIVA UV telescope. ---------------------------------------------------------------------------------------------------- [JAD 9, 8B] GAIA photometry performances C. Jordi, F. Figueras, J.M. Carrasco GAIA will measure all detected sources with a broad-band photometer (BBP) implemented by 4 or 5 bands in the focal plane of the astrometric telescopes (Astro-1 and Astro-2). The sources down to V=20 will also be detected and measured with a medium-band photometer (MBP) implemented by 10-12 bands in the focal plane of the smaller telescope (Spectro). The aim of this paper is to review the current design of the instruments and the estimated attainable accuracies of the stellar parameters for some galactic populations. ---------------------------------------------------------------------------------------------------- [JAD 9, 8C] Testing the GAIA performance on photometry of eclipsing binaries: the case of near-contact and contact binaries P.G. Niarchos and V.N. Manimanis The physical parameters of four eclipsing binaries (two near-contact and two contact) are derived by using ground based photometric observations and HIPPARCOS/Tycho photometric data, which mimic the photometric observations that should be obtained by GAIA. The results are compared and the achievable precision of the basic stellar parameters derived by GAIA photometry is discussed. ---------------------------------------------------------------------------------------------------- [JAD 9, 8D] The minimum distance method of classification using linear interpolation with its applications to simulated GAIA photometry V. Malyuto A modification of the minimum distance method (or template matching) of classification has been tested where with the addition of a likelihood procedure. This two-stage combined method provides continuous classification with linear interpolation. The method has been applied to a grid of simulated GAIA photometric data produced by C. Bailer-Jones. The classification accuracies at different magnitudes have been estimated for a wide range of the fundamental parameters: effective temperature, gravity and metallicity. ---------------------------------------------------------------------------------------------------- [JAD 9, 8E] Combining DIVA images: detecting visual binaries with large magnitudedifferences P. Nurmi During the observational phase of the DIVA satellite several images are obtained from the same object at different epochs and transit angles. Hence, it is scientifically important to combine the images to produce one "super'' image that contains all the data. This allows us to find much fainter stars than those that can be detected in single images. Most of the emerging objects are physical secondary stars in binaries, but also some background objects will be found. The combination procedure also increases the image resolution, especially in the cross-scan direction. The combination procedure is somewhat more complicated than those used in traditional image combining problems. This is mainly due to two main differences. Firstly, DIVA pixels are binned 1 x 4 pixels and secondly, transit angles, i.e. image rotations, can have all the values between0 and 360degrees, which are generally not uniformly distributed. Also, the DIVA field is not a square, but it is elongated in the cross-scan direction. The developed image combination procedure uses a drizzling method as its basic idea. The drizzling method is used in many image combining problems that need to be fast and handle undersampled shifted and rotated images. We show some preliminary results of the image combination and illustrate the basic reduction procedure that could be used to detect faint companions around primary stars. By estimating the efficiency of the current image detection method we conclude that at distances of a few arc-seconds the drizzling method can reveal very faint objects and is especially efficient, but at sub-pixel level, the detection of faint companions becomes more difficult but not impossible. However, even in the worst possible scenario the combining procedure can provide a considerable amount of new binary detections ---------------------------------------------------------------------------------------------------- [JAD 9, 8F] On the detectability of light curves of Kuiper Belt objects P. Lacerda We present a statistical study of the detectability of light curves of Kuiper Belt objects (KBOs). Some Kuiper Belt objects display light curves that appear "flat", i.e., there are no significant brightness variations within the photometric uncertainties. Under the assumption that KBO light curves are mainly due to shape, the lack of brightness variations may be due to (1) the objects have very nearly spherical shapes, or (2) their rotation axes coincide with the line of sight. We investigate the relative probabilities of these two effects, and how they relate to the intrinsic shape distribution of KBOs. This study suggests that the fraction of KBOs with detectable brightness variations may provide clues about the shape distribution of these objects. Although the current database of rotational properties of KBOs is still insufficient to draw any statistically meaningful conclusions, we expect that, with a larger dataset, this method will provide a useful test for candidate KBO shape distributions. ---------------------------------------------------------------------------------------------------- [JAD 9, 8G] Ground-based Astrometry before GAIA and DIVA M. Stavinschi After the success of Hipparcos, and in the perspective of the future astrometric space missions such as DIVA and GAIA, we discuss the role of small telescopes and the development ofground-based astrometry. Several photometric and astrometric programs, that could be performed with small instruments existing in the observatories of different countries, are proposed.