author = "Santos, Leonardo Barbosa Torres dos and Prado, Antonio Fernando 
                         Bertachini de Almeida and Merguizo Sanchez, Diogo",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Lifetime of a spacecraft around a synchronous system of asteroids 
                         using a dipole model",
              journal = "Astrophysics and Space Science",
                 year = "2017",
               volume = "362",
               number = "11",
                month = "Nov.",
             keywords = "Celestial mechanics, Minor planets asteroid, Restricted 
                         synchronous four-body problem.",
             abstract = "Space missions allow us to expand our knowledge about the origin 
                         of the solar system. It is believed that asteroids and comets 
                         preserve the physical characteristics from the time that the solar 
                         system was created. For this reason, there was an increase of 
                         missions to asteroids in the past few years. To send spacecraft to 
                         asteroids or comets is challenging, since these objects have their 
                         own characteristics in several aspects, such as size, shape, 
                         physical properties, etc., which are often only discovered after 
                         the approach and even after the landing of the spacecraft. These 
                         missions must be developed with sufficient flexibility to adjust 
                         to these parameters, which are better determined only when the 
                         spacecraft reaches the system. Therefore, conducting a dynamic 
                         investigation of a spacecraft around a multiple asteroid system 
                         offers an extremely rich environment. Extracting accurate 
                         information through analytical approaches is quite challenging and 
                         requires a significant number of restrictive assumptions. For this 
                         reason, a numerical approach to the dynamics of a spacecraft in 
                         the vicinity of a binary asteroid system is offered in this paper. 
                         In the present work, the equations of the Restricted Synchronous 
                         Four- Body Problem (RSFBP) are used to model a binary asteroid 
                         system. The main objective of this work is to construct grids of 
                         initial conditions, which relates semi- major axis and 
                         eccentricity, in order to quantify the lifetime of a spacecraft 
                         when released close to the less massive body of the binary system 
                         (modeled as a rotating mass dipole). We performed an analysis of 
                         the lifetime of the spacecraft considering several mass ratios of 
                         a binary system of asteroids and investigating the behavior of a 
                         spacecraft in the vicinity of this system. We analyze direct and 
                         retrograde orbits. This study investigated orbits that survive for 
                         at least 500 orbital periods of the system (which is approximately 
                         one year), then not colliding or escaping from the system during 
                         this time. In this work, we take into account the gravitational 
                         forces of the binary asteroid system and the solar radiation 
                         pressure (SRP). We found several regions where the direct and 
                         retrograde orbits of a spacecraft survive throughout the 
                         integration time (one year) when the solar radiation pressure is 
                         taken into account. Numerical evidence shows that retrograde 
                         orbits have a larger region initial conditions that generate 
                         orbits that survive for one year, compared to direct orbits.",
                  doi = "10.1007/s10509-017-3177-x",
                  url = "http://dx.doi.org/10.1007/s10509-017-3177-x",
                 issn = "0004-640X",
             language = "en",
           targetfile = "santos_lifetime.pdf",
        urlaccessdate = "28 nov. 2020"