This review presents a scientometric and text-mining analysis of publications related to f(Q) gravity, dark energy, and cosmology based on literature indexed in the Scopus database from 2021 to 2023. Using tools such as VOSviewer and Biblioshiny, this study identified influential publications, prominent authors, recurring keywords, and emerging research trends. Co-occurrence analysis revealed that topics such as nonmetricity, wormholes, cosmic acceleration, and observational constraints dominate the current research landscape. Citation network mapping and thematic clustering expose the evolution of dominant research fronts, including extensions to anisotropic models, wormhole physics, and modified gravity frameworks that incorporate non-commutative geometry and teleparallelism. The results showed an exponential increase in publication numbers, indicating a proliferating interest with more academic involvement in the field. The analysis maps the relationship between fundamental theoretical advancements and the observational datasets, like Pantheon and BAO, representing a growing intersection between datadriven science and theoretical cosmology. The study emphasizes research contributions across the globe. In short, this scientometric analysis provides a thorough overview of how f(Q) gravity is configuring modern research in cosmology and astrophysics.
In May, 2024 a severe solar storm with strong geomagnetic storm components was recorded. Based on optical observation of low Earth orbit (LEO) satellites during and after the solar event, we describe and make available a database featuring topocentric observations for more than 300 LEOs, and present the analysis of the storm's impact on the satellites' orbital positions. Between May 10 and May 15, on several nights, we performed a series of observations on LEOs from Cluj-Napoca, Romania, and the Feleacu Station of the Astronomical Observatory Cluj-Napoca. Two instruments were used: a wide Field of View instrument based on an 85 mm lens with a DSLR camera, and a narrow Field of View instrument based on an Orion ShortTube 80 refractor telescope, with a SBIG STT 1603ME CCD camera. These observations were gathered in a database with information about the instrument used and location, the satellite's identifier, time of observation, and the topocentric position. This database contains over 300 satellites. In the second part of this study, we used these observations to compare the observed apparent positions with the predicted positions computed from the up-to-date Two-Line Elements (TLEs), available in the USSPACECOM catalog. An initial investigation of this comparison leads us to identify satellites that underwent active space maneuvers (ASM), with most satellites belonging to the Starlink constellation. Additionally, we plotted and investigated the distribution of O-C values for ASM and non-space maneuvered (NSM) satellites during the solar storm. Among all surveyed satellites, prediction errors for ASM satellites were significantly larger when compared to NSM satellites. These differences are illustrated in plots of ASM versus NSM satellites. We found that O-C errors were driven primarily by active maneuvers, rather than by the G5 geomagnetic storm itself.
tau Ceti is a G-type main-sequence star (spectral type G8 V) and a member of Population II. Because of its proximity, similarity to the Sun, and the presence of a planetary system, it has long served as a benchmark object in stellar astrophysics. Its fundamental parameters have been extensively determined through observational surveys, theoretical analyses, and interior structure modeling. In this study, we focus on the atmospheric modeling of tau Ceti. Whereas interior models are primarily constrained by global properties such as stellar radius and mass, the atmospheric model provides access to the detailed thermodynamic structure of the star. In particular, we examine the variation of mass depth, temperature, pressure, density, and electron number density as functions of Rosseland optical depth (tau R), thereby establishing a self-consistent framework for characterizing the stellar atmosphere. This framework further enables the generation of synthetic spectra, which can be directly compared with observational data to test the validity of the model.
In 1990, the initiative of publishing an academic journal devoted to astronomy and astrophysics was agreed by the Romanian Academy. The Romanian Astronomical Journal is now 35 years old. This journal is now quoted into the Web of Science and indexed by various international databases.
This study explores the potential of fractal and complexity metrics in classifying open and globular stellar clusters, providing a nuanced perspective on their structural differences. Using a dataset of 20 open clusters and 20 globular clusters selected from the Messier Catalogue - due to their historical significance, availability in standardized formats, and high image quality - eight grayscale and eight binary metrics were applied to assess their effectiveness in distinguishing between these two classes. Although the sample size is modest, it was deliberately curated to ensure balance, comparability, and suitability for a first-stage methodological evaluation of fractal analysis in astronomy. This framework lays the groundwork for broader applications in future research. Among the grayscale metrics, Higuchi 2D Dimension emerged as the most effective, achieving complete separation with no overlap between the two classes. For with minimal overlap. Complementary metrics, such as Lacunarity and Correlation Dimension, provided additional insights into the texture and spatial distribution of stellar clusters, though their utility for standalone classification was limited by moderate overreduced sensitivity in capturing subtle structural differences. The study employed overlap analysis and box-plot visualizations to identify key discriminative metrics, supcomplex systems, demonstrating the utility of fractal metrics in complementing traditional photometric and spectroscopic approaches.
