Articles written in Journal of Astrophysics and Astronomy

    • Trajectory of asteroid 2017 SB20 within the CRTBP


      More Details Abstract Fulltext PDF

      Regular monitoring the trajectory of asteroids to a future time is a necessity, because the variety of known probably unsafe near-Earth asteroids are increasing. The analysis is perform to avoid any incident or whether they would have a further future threat to the Earth or not. Recently a new Near Earth Asteroid (2017 SB20) has been observed to cross the Earth orbit. In view of this we obtain the trajectory of Asteroid in the circular restricted three body problem with radiation pressure and oblateness.We examine nature of Asteroid’sorbit with Lyapunov Characteristic Exponents (LCEs) over a finite intervals of time. LCE of the system confirms that the motion of asteroid is chaotic in nature. With the effect of radiation pressure and oblateness the length of curve varies in both the planes. Oblateness factor is found to be more perturbative than radiation pressure. To see the precision of result obtain from numerical integration we show the error propagation and the numerical stability is assured around the singularity by applying regularized equations of motion for precise long-term study.

    • Halo orbit of regularized circular restricted three-body problem with radiation pressure and oblateness


      More Details Abstract Fulltext PDF

      In this paper, computation of the halo orbit for the KS-regularized photogravitational circular restricted three-body problem is carried out. This work extends the idea of Srivastava et al. (Astrophys. Space Sci. 362: 49, 2017) which only concentrated on the (i) regularization of the 3D-governing equations of motion, and (ii) validation of the modeling for small out-of-plane amplitude ($A_z = 110000$ km) assuming the third order analytical approximation as an initial guess with and without differential correction. This motivated us to compute the halo orbits for the large out-of-plane amplitudes and to study their stability analysis for the regularized motion. The stability indices are described as a function of out-of-plane amplitude, mass reduction factor and oblateness coefficient. Three different Sun–planet systems: the Sun–Earth, Sun–Mars and the Sun–Jupiter are chosen in this study. Stable halo orbits do not exist around the $L_1$ point, however, around the $L_2$ point stable halo orbits are found for the considered systems.

    • Lissajous motion near Lagrangian point $L_2$ in radial solar sail


      More Details Abstract Fulltext PDF

      An attempt was made to study the dynamics close to the collinear libration point $L_2$ of the radial solar sail circular-restricted three-body problem (RSCRTBP) in the Sun–Jupiter System, where the third massless body is a solar sail.We analyse the qausi-periodic (Lissajous solutions) orbits about the libration point $L_2$. The Lindstedt–Poincaré approximation for the qausi-periodic orbitswas used for numerical simulations.We utilized linear quadratic regulator (LQR) to stabilize the full nonlinear model, and linear state-feedback controller was designed to stabilize the trajectory.

  • Journal of Astrophysics and Astronomy | News

    • Continuous Article Publication

      Posted on January 27, 2016

      Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.