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Dmitry Pritykin

Publications and source records attributed to Dmitry Pritykin.

3 recordsLinked to original sources

Asteroid Mining to Sustain a Mars Colony: A Logistics Point of View

Asteroid mining can become an enabling technology to establish a sustainable manned colony on Mars, which requires metallic materials more often than they are readily available in shipments from Earth. This paper describes a feasibility study of a supply chain that delivers metals extracted from metallic asteroids to Mars. The asteroids are selected to respect the $\Delta V$ limits imposed by up-to-date spacecraft. The study is conducted with reference to the state of the art in space transportation technologies and in-situ resource utilization. A possibility for mining on carbonaceous asteroids to produce the propellant required for return trips is also taken into account. Different supply chains are computed through a multi-objective optimization routine that considers the mission $\Delta V$, the mass of extracted metals and the mass of propellant produced on the asteroids. Schedules to visit the asteroids within reach are obtained and the total mass of the delivered material is evaluated for various mining rates. Finally, the use of the metallic material to build habitats and rovers on the Martian soil through additive manufacturing is discussed.

astro-ph.IM

Defunct Satellites in Nearly Polar Orbits: Long-term Evolution of Attitude Motion

Low Earth orbits (LEO) are known as a region of high space activity and, consequently, space debris highest density. Launcher upper stages and defunct satellites are the largest space debris objects, whose collisions can result in still greater pollution, rendering further space missions in LEO impossible. Thus, space debris mitigation is necessary, and LEO region is a primary target of active debris removal (ADR) projects. However, ADR planning requires at least an approximate idea of the candidate objects' attitude dynamics, which is one of the incentives for our study. This paper is mainly focused on modeling and simulating defunct satellites. The model takes into account the gravity gradient torque and the torque due to eddy currents induced by the interaction of conductive materials with the geomagnetic field. A better understanding of the intermediate phase of the exponential deceleration is achieved owing to a more accurate model of the eddy currents torque than in most prior research. We also show the existence of other important factors in the studied dynamics such as evolution of the orbit itself and the residual magnetic moment, which both contribute to the overall attitude motion evolution and the variety of the final regimes.

physics.space-ph

Long-term Attitude Dynamics of Space Debris in Sun-synchronous Orbits: Cassini Cycles and Chaotic Stabilization

Comprehensive analysis of space debris rotational dynamics is vital for active debris removal missions that require physical capture or de-tumbling of a target. We study the attitude motion of used rocket bodies acknowledgedly belonging to one of the categories of large space debris objects that pose an immediate danger to space operations in low Earth orbits. Particularly, we focus on Sun-synchronous orbits (SSO) with altitudes in the interval 600-800 km, where the density of space debris is maximal. Our mathematical model takes into account the gravity gradient torque and the torque due to eddy currents induced by the interaction of conductive materials with the geomagnetic field. Using perturbation techniques and numerical methods we examine the deceleration of the initial fast rotation and the subsequent transition to a relative equilibrium with respect to the local vertical. A better understanding of the latter phase is achieved owing to a more accurate model of the eddy currents torque than in most prior research. We show that SSO precession is also an important factor influencing the motion properties. One of its effects is manifested at the deceleration stage as the angular momentum vector oscillates about the direction to the south celestial pole.

physics.space-ph