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"Exciting results are blooming, thanks to a convergence between unprecedented asteroseismic data obtained by the satellites CoRoT and KEPLER, and state-of-the-art models of the internal structure of red giants and of galactic evolution. The pulsation properties now available for thousands of red giants promise to add valuable and independent constraints to current models of structure and evolution of our galaxy. Such a close connection between these domains opens a new very promising gate in our understanding of stars and galaxies. In this book international leaders in the field offer a wide perspective of the recent advancements in, asteroseismology of red giants, models of the atmosphere, internal structure, and evolution of red giants, and stellar population synthesis and models of the Milky Way."

"This book is revised and extended to include using a low-cost "go-to" telescope, there are various pitfalls to be avoided, and how this class of instrument can make amateur astronomy more accessible to those with limited time at their disposal. It also discusses the new breed of mid-range digital cameras that include powerful on-board processing and image enhancement software that used to be available only to people with advanced astronomical CCD cameras. Finally, there are detailed reviews and test reports on some of the budget telescopes that are available on main street and by mail order."

"Transmission grating spectroscopes look like simple filters and are designed to screw into place on the eyepiece of a telescope for visual use, or into the camera adapter for digicam or CCD imaging. Using the most popular commercially made filter gratings. Rainbow Optics (US) and Star Analyzer (UK), as examples, this book provides the reader with information on how to set up and use the grating one needs to obtain stellar spectrograms. It also discusses several methods on analyzing the results. This book is written in an easy to read style, perfect for getting started on the first night using the spectroscope, and specifically showing how the simple transmission filter is used on the camera or telescope. No heavy mathematics or formulas are involved, and there are many practical hints and tips, something that is almost essential to success when starting out. This book helps readers to achieve quick results, and by following the worked examples, they can successfully carry out basic analysis of the spectra."

"Symposium 7 of the JENAM 2010 aimed at bringing these diverse opportunities to the attention of both theoretical and observational astronomers working at all wavelengths, including the potential for synergies with other facilities. The meeting highlighted the scientific potential of the SKA, discussed scientific priorities and their impact on the design of the SKA, explored the synergies between the SKA and other next-generation astronomical facilities in different wavelength domains such as the ALMA, ELTs, LSST, JWST, GRE, IXO, Gaia and Euclid, and high-energy facilities (Auger), explored the ?cyber?infrastructure? that may become available for the distribution and distributed analysis of SKA data. "

"Menguji validitas relativitas umum dapat dilakukan dengan memodifikasinya untuk mencari penyimpangan. Beberapa teori gravitasi termodifikasi menghasilkan potensial gravitasi dengan suku eksponensial yang menyerupai potensial Yukawa untuk aproksimasi medan lemah. Walaupun pengujian eksperimental dari koreksi Yukawa masih terbatas pada skala sistem tata surya, beberapa penelitian terbaru telah menggunakan data dari kurva rotasi galaksi untuk membatasi parameter Yukawa ini secara observasional, namun dengan asumsi bahwa barion terkopel secara lemah dengan gravitasi untuk memenuhi batasan gravitasi lokal. Studi kami mengabaikan asumsi ini dan menganalisis suku koreksi Yukawa baik dalam halo materi gelap maupun komponen bariyonik. Kami menyelidiki empat model: Newton, Almeida, MG, dan MG Duo, berdasarkan keberadaan suku koreksi Yukawa dalam komponennya dan kopling antar jenis partikel. Kami menguji keempat model ini pada tiga set data yang berbeda dari galaksi Bima Sakti, termasuk data Sofue (2015, 2017, dan 2020) dan data kurva rotasi dari Gaia DR3 oleh Wang (2023) dan Zhou (2023). Kami menemukan dukungan statistik yang kuat melalui faktor Bayes untuk model MG Duo yang menunjukkan kopling terpisah antara baryon-baryon dan baryon-DM. Namun, data observasional yang lebih tepat yang mencakup rentang radius galaksi yang lebih luas masih diperlukan untuk meningkatkan pemahaman tentang modifikasi di wilayah dalam galaksi Bima Sakti.

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Testing the validity of general relativity can be done by modifying it to search for potential deviations. Several modified gravity theories introduce a Yukawa-like exponential term in the gravitational potential for weak-field limits. While experimental tests of the Yukawa-correction are limited to Solar system scales, recent studies have used galactic rotation curve data to observationally constrain these Yukawa parameters, although assuming that baryons are weakly coupled to gravity to satisfy local gravity constraints. In our study, we relax this assumption and analyze the Yukawa-correction in both dark matter halo and baryonic components. We investigate four models: Newtonian, Almeida, MG and MG Duo models, based on the presence of the Yukawa-correction term in the components and the coupling between particle species. We tested these models on three Milky Way datasets: Sofue (2015, 2017, 2020) and rotation curves by Wang (2023) and Zhou (2023) derived from Gaia DR3 data. We find strong statistical favor through the Bayes factor for the MG Duo model that presents a separated coupling between baryon-baryon and baryon-DM. However, more precise observational data covering a broader range of galactic radii is still required to enhance our understanding of modifications in the inner regions of the Milky Way."

"There are 'voids' obscuring all kinds of objects in the cosmos. Voids may be within an object, or between an object and us. Dark nebulae, dark lanes, and dust lanes looks out into the deep sky at those apparent dark regions in space, which are among the most compelling telescopic destinations for amateur observers. One famous example is Barnard's dark nebulae, those striking dark clouds set against the background of stars in the milky way. This book explains the optimal ways to observe each object in detail."

"This textbook focuses on fundamental and sometimes practical limitations on the ultimate performance that an astronomical system may reach, rather than presenting particular systems in detail. In little more than a decade there has been extraordinary progress in imaging and detection technologies, in the fields of adaptive optics, optical interferometry, in the sub-millimetre waveband, observation of neutrinos, discovery of exoplanets, to name but a few examples. The work deals with ground-based and space-based astronomy and their respective fields. And it also presents the ambitious concepts behind space missions aimed for the next decades. Avoiding particulars, it covers the whole of the electromagnetic spectrum, and provides an introduction to the new forms of astronomy becoming possible with gravitational waves and neutrinos. It also treats numerical aspects of observational astrophysics, signal processing, astronomical databases and virtual observatories."