Astrophys Space Sci ( 2018) 363:14 https://doi.org/10.1007/s10509-017-3234-5 ORIGINAL ARTICLE Analysis of impulsive maneuvers to keep orbits around the asteroid 2001SN 263 Willer G. Santos 1 · Antonio F.B.A. Prado 1 · Geraldo M.C. Oliveira 1,2 · Leonardo B.T. Santos 1 Received: 15 August 2017 / Accepted: 7 December 2017 © Springer Science+Business Media B.V., part of Springer Nature 2017 Abstract The strongly perturbed environment of a small body, such as an asteroid, can complicate the prediction of orbits used for close proximity operations. Inaccurate pre- dictions may make the spacecraft collide with the aster- oid or escape to the deep space. The main forces acting in the dynamics come from the solar radiation pressure and from the body’s weak gravity field. This paper investigates the feasibility of using bi-impulsive maneuvers to avoid the aforementioned non-desired phenomena (collisions and es- capes) by connecting orbits around the triple system asteroid 2001SN 263 , which is the target of a proposed Brazilian space mission. In terms of a mathematical formulation, a recently presented rotating dipole model is considered with oblate- ness in both primaries. In addition, a “two-point boundary value problem” is solved to find a proper transfer trajec- tory. The results presented here give support to identify- ing the best strategy to find orbits for close proximity op- erations, in terms of long orbital lifetimes and low delta- V consumptions. Numerical results have also demonstrated the significant influence of the spacecraft orbital elements (semi-major axis and eccentricity), angular position of the Sun and spacecraft area-to-mass ratio, in the performance of the bi-impulsive maneuver. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10509-017-3234-5) contains supplementary material, which is available to authorized users. B W.G. Santos willer.gomes@inpe.br 1 Space Engineering Department, National Institute for Space Research, São José dos Campos 12227010, Brazil 2 Federal Center for Technological Education of Minas Gerais (CEFET-MG), Contagem, Brazil Keywords Impulsive maneuvers · Near-earth asteroids · Close proximity operations · Irregular bodies · Astrodynamics 1 Introduction Since the discovery of the first asteroid, Ceres (currently classified as a minor planet), in 1801 by Giuseppe Piazzi, many others similar objects have been found (Bowell et al. 1994; Tedesco and Desert 2002). At present, approximately 600,000 asteroids (Libourel and Corrigan 2014) in the as- teroid belt known, and, very likely, there are millions more. When the orbit of a main belt asteroid is within 1.3 AU from the Sun—where the term AU represents the Astronomical Unit, which is a unit of length, roughly the average distance from the Earth to the Sun, i.e., 149.597.871 km—or within 0.3 AU of the Earth’s orbit, then such object is classified as a near-Earth asteroid (NEA). They are grouped into three categories: Apollos, representing 54.6% of the total NEAs; Amor (37.1% of NEAs); and Atens (8.3% of NEAs). When the orbit of a NEA is less than 0.05 AU (about 7.5 million kilometers) from the orbit of the Earth and when their di- ameter exceed 150 m, they are classified as potentially haz- ardous asteroids (PHAs). The risk of collisions justifies the increasing interest from space agencies around the world in exploring and studying this kind of object. However, this is not the only reason. According to Lewis (1996), an asteroid with one kilo- meter of diameter and two billion tons of mass would con- tain, for instance, about 7500 tons of platinum, representing a monetary value of more than $150 billion. Furthermore, from the scientific point of view, it is believed that most of the NEAs still preserve information as regards the ori- gin of the solar system. Several missions have been sched-