Design of a low thrast propulsion system and the trajectories of spasecraft to the centre of the solar system

The article is devoted to the peculiarities of the flight trajectories design to the centre of the Solar system for two perspective Russian spacecrafts. A scientific goal of the project is to study the near-solar space from close distances (60-80 solar radii) and non-ecliptic inclinations. As part of the draft project, management decided to create two space- crafts (SC), where an option with a “chemical” propulsion system based on low-thrust engines is offered as a march. In connection with a significant increase in the initial mass of the spacecraft, it is necessary to use means of deducing a heavier class. Therefore, now options are being considered for launching at “Angara-A5” and “Soyuz-5” (“Sumkar”) with “DM” and “Fregat-SBU” upper stages from the Vostochny and Baikonur launch sites. The active life of the SC should exceed seven years, for which an inclination of more than 25 ° must be achieved. The article describes the additional version of the propulsion system with the use of two-component engines, pro- duced by NIIMash (Nizhnyaya Salda), and the main characteristics of the flight schemes for two spacecrafts are indi- cated. The developed scheme of the first spacecraft flight assumes the launch in August 2026. Convergence with the Sun at a minimum distance of 61.5 solar radii occurs 6 years after the start. After the last, the eighth, gravitational maneu- ver, 8.3 years after launching the spacecraft reaches heliocentric latitude of 33.1°. The trajectory of the second space- craft assumes the launch in April 2028. Six years after the start it also approaches the Sun to approximately the same distance 63.0 solar radii. The spacecraft reaches the heliocentric latitude of 29.1° with the help of subsequent gravity- assists at Venus. The presented design appearance of the ‘chemical’ propulsion system with the use of low-thrust engines makes it possible to achieve the specified parameters of the Sun orbit and to execute the scientific program within the given period of active existence of two spacecrafts.