Astronomiske observationer: observatorier, udstyr og metoder

A star in a binary may interact with its companion and this complicates significantly its structure and evolution. During several decades in the past many astronomers hoped that the number of binaries is small. This is sometimes reflected in theoretical studies dealing with large populations of stars where it is ASSUMED (without any justification) that binaries do not alter the results. The number of confirmed binaries increases as observations improve and we there­ fore thought that the time was right to organize a meeting where the main topic would be the effect of binaries on stellar population studies. The SOC proposed a program with extended general overviews and highlights of non-evolved and evolved binaries, with low mass, intermediate mass and massive components, the link with supernova explosions, pulsars and gamma-ray bursts, the effect of binaries on the chemical evo­ lution of galaxies. Specialists in the different research fields were invited and have given very interesting and highly educational talks. As can be noticed by reading the proceedings, the authors have put a lot of effort in preparing their contribution.

The volume of data being collected in solar astronomy has exponentially increased over the past decade and we will be entering the age of petabyte solar data. Deep learning has been an invaluable tool exploited to efficiently extract key information from the massive solar observation data, to solve the tasks of data archiving/classification, object detection and recognition.Astronomical study starts with imaging from recorded raw data, followed by image processing, such as image reconstruction, inpainting and generation, to enhance imaging quality. We study deep learning for solar image processing. First, image deconvolution is investigated for synthesis aperture imaging. Second, image inpainting is explored to repair over-saturated solar image due to light intensity beyond threshold of optical lens. Third, image translation among UV/EUV observation of the chromosphere/corona, Ha observation of the chromosphere and magnetogram of the photosphere is realized by using GAN, exhibiting powerful image domain transfer ability among multiple wavebands and different observation devices. It can compensate the lack of observation time or waveband. In addition, time series model, e.g., LSTM, is exploited to forecast solar burst and solar activity indices.This book presents a comprehensive overview of the deep learning applications in solar astronomy. It is suitable for the students and young researchers who are major in astronomy and computer science, especially interdisciplinary research of them.

My principal aim in writing this book was to present a wide range of astrophysical topics in sufficient depth to give the reader a general quantitative understanding of the subject. The book outlines cosmic events but does not portray them in detail-it provides aseries of astrophysical sketches. I think this approach befits the present uncertainties and changing views in astrophysics. The material is based on notes I prepared for a course aimed at seniors and beginning graduate students in physics and astronomy at Cornell. This course defined the level at which the book is written. For readers who are versed in physics but are unfamiliar with astronomical terminology, Appendix A is included. It gives a brief background of astronomical concepts and should be read before starting the main text. The first few chapters outline the scope of modern astrophysics and deal with elementary problems concerning the size and mass of cosmic objects. However, it soon becomes apparent that a broad foundation in physics is needed to proceed. This base is developed in Chapters 4 to 7 by using, as ex am pIes, specific astronomi- cal situations. Chapters 8 to 10 enlarge on the topics first outlined in Chapter I and show how we can obtain quantitative insights into the structure and evolution of stars, the dynamics of co~mic gases, and the large-scale behavior of the universe.

Pulsating and eccentric binary stars play a fundamentally important role in deciphering the mass distribution within stars. The present volume reviews the fundamental concepts of both radial and nonradial oscillations in the stars, including the Sun. Helio- and astroseismological results are reviewed, from the basics to the most recent developments. A new theory is presented, which seems to explain the mechanism of the light and radial velocity variations of recently discovered Ap stars. This textbook covers almost all kinds of variable stars of widely different characteristics. It will serve as a reference text for a very long time to come, not only for specialists but also for undergraduate students of physics and astronomy.

The exploration of our Solar System is rapidly growing in importance as a scientific discipline. During the last decades, great progress has been achieved as the result of space missions to planets and small bodies - as- teroids and comets - and improved remote-sensing methods, as well as due to refined techniques of laboratory measurements and a rapid progress in theoretical studies, involving the development of various astrophysical and geophysical models. These models are based, in particular, on the approach of comparative planetology becoming a powerful tool in revealing evolu- tionary processes which have been shaping the planets since their origin. Comets and asteroids, being identified as remnants of planetary formation, serve as a clue to the reconstruction of Solar System history because they encapsulated the primordial material from which the planets were built up. At the same time, these interplanetary carriers of original matter and mes- sengers from the past, being triggered by dynamical processes well outside our neighboring space, were responsible for numerous catastrophic events when impacting on the planets and thus causing dramatic changes of their natural conditions. In the crossroads of astronomy and geophysics, recent years have seen a growing understanding of the importance of collisional processes through- out the history of the Solar System and, therefore, the necessity to get more insight into the problem of interactions of planets and small bodies.

This book is the proceedings of a workshop on stellar continuum radio astronomy that was held in BoUlder, Colorado on August 8-10, 1984. Although it was originally intended to be a small workshop with participants mainly from North America, it evolved to a workshop with 72 partiCipants from twelve countries (U.S.A. 52, Canada 3, the Netherlands 3, United Kingdom 3, Australia 2, Ireland 2, Italy 2, France 1, Mexico 1, Switzerland 1, West Germany 1, and U.S.S.R. 1). This workshop was sponsored by the Joint Institute of Laboratory Astrophysics (JILA) and the University of Colorado. In order to preserve a workshop atmosphere, while still presenting both extensive reviews and contributed papers, an experimental format was adopted. All contributed papers related to the topiCS of the day were presented in poster form in the early morning and were accessible all day. During each morning (or afternoon) session review papers were presented, followed by a coffee break in the poster area adjacent to the conference room. Then the review papers and contributed papers were discussed for roughly one and a half hours. The last session was devoted to invited panel papers and discussion of current and future problems in the field of stellar radio astronomy.

The near Infra-Red emission of the Interstellar Medium is a very puzzling subject. In the brightest regions, where spectroscopic observa- tions are possible from the ground, several bands (3.3 - 3.4 - 6.2 - 7.7 - 8.6 - 11.3 ~m) have been observed since 1973. The absence of satisfying explanation was so obvious that they were called "e;Unidenti- fied IR Emission Bands"e;. The puzzle still increased when were known the first results of the general IR sky survey made by the satellite IRAS. On a large scale, the near IR emission of the Interstellar medium was expected to be very small but it was observed to be about one third of the total IR emission for our own galaxy ..* The situation has moved in 1984 when it was suggested that a class of stable organic molecules, the Polycyclic Aromatic Hydrocarbons (PAH's) could be at the origin of this near IR emission. Initially based on the required refractory character of particules that should be heated to high temperature without subliming, this hypothesis leads to a sugges- tive spectroscopic similarity with the observed astronomical bands. This hypothesis is attractive and it has many implications, for ins- tance, the PAHs would be the most abundant organic molecules in the universe. However, many points have to be clarified and the different consequences of this suggestion should be explored.