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The study of motion of a test mass in the vicinity of an equilibrium point under the frame of restricted three body problem (RTBP) plays an important role in the trajectory design for different space missions. In this paper, motion of an infinitesimal mass has been described under the frame of Jupiter-Europa system with oblateness. At first, we have determined equilibrium points and then performed linear stability tests under the influence of oblateness of both the primaries. We found that due to oblateness, a considerable deviation in the existing results has occurred. Next, we have computed tadpole and horseshoe orbits in the neighbourhood of triangular equilibrium points and then the oblateness effect is recorded on these orbits. Finally, the evolution of orbits of infinitesimal mass about triangular equilibrium points have been estimated by using Poincaré surface of section technique and it is noticed that in presence of oblateness, quasi-periodic orbit dominates over the chaotic zones. These results will help in further study of more generalised models with perturbations.

Asteroids pose significant threats to Earth, necessitating early detection for potential deflection. Leveraging machine learning (ML), we classify asteroids into near-Earth Asteroids (particularly Atens, Amors, Apollos, and Apoheles) and non-near-Earth asteroids, further categorizing them based on hazard potential. Training the seven models on a comprehensive data set of 4687 asteroids, we achieve high accuracy in prediction. The predictive capability of these models is critical for informed decision-making in planetary defense strategies. We apply different regularization techniques to prevent overfitting and validate the models using a large unseen data set. A rigorous long-term N -body integration spanning 1 Myr is executed utilizing the Mercury N -body integrator to illuminate the evolution of asteroid properties over extended temporal scales. Following this integration process, the best-performing ML model is employed to classify asteroids based on their orbital characteristics and hazardous status respectively. Our findings highlight the effectiveness of ML in asteroid classification and prediction, paving the way for large-scale applications. By dividing a 1 Myr integration into intervals, we uncover temporal trends in asteroid behaviour, revealing insights into hazard evolution and ejection patterns. Notably, initially, hazardous asteroids tend to transition to non-hazardous states over time, elucidating key dynamics in planetary defense. We illustrate these findings through plotted graphs, providing valuable insights into asteroid dynamics. These insights are instrumental in advancing our understanding of long-term asteroid behaviour, with significant implications for future research and planetary protection efforts. [ABSTRACT FROM AUTHOR]

Background: The United Nations Children's Fund and global partners define an orphan as a child who has lost one or both parents. Orphanages, children's villages, or other group residential facilities generally fail to meet young people's emotional and psychological needs. Research indicates that orphaned youth face more negative psychosocial challenges than their younger counterparts do. This study was carried out to find out the association of the psychological well-being of adolescent orphans with the selected demographic variables. Methods: A descriptive, cross-sectional study was carried out among 115 adolescent orphans in orphanage of the Srinagar district between July 2020 and February 2021 using standardized psychological well-being scale given by Carol Ryff. Association of psychological well-being, with its dimensions, and selected demographic variables were assessed. Results: Group mean difference on psychological well-being revealed that double-orphan adolescents have significantly lower psychological well-being as compared to the half-orphan adolescents. The study also revealed that habitat was significantly associated with overall psychological well-being and one of the dimensions of psychological well-being, i.e., positive relations with others. Educational status was found to have a significant association with the autonomy dimension of psychological well-being only, where as the type of orphan shows a significant association with overall psychological well-being and self-acceptance dimension of psychological well-being. Time spent in orphanage also shows significant association with purpose in life and self-acceptance dimension of psychological well-being. Conclusions: There is a need for organized social support to improve the physical and psychological health of orphans. [ABSTRACT FROM AUTHOR]