author = "Ferreira, Alessandra Ferraz da Silva and Prado, Antonio Fernando 
                         Bertachini de Almeida and Winter, Othon Cabo",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Universidade Estadual 
                         Paulista (UNESP)}",
                title = "A numerical study of powered swing-bys around the moon",
              journal = "Advances in Space Research",
                 year = "2015",
               volume = "56",
               number = "2",
                pages = "252--272",
                month = "July",
             keywords = "Powered Swing-By, Astrodynamics, Orbital maneuvers, Close-approach 
             abstract = "The present research studies Swing-By maneuvers combined with the 
                         application of an impulse at the spacecraft periapsis passage. The 
                         studies were made for different values of r(p) (periapsis 
                         distance), delta V (magnitude of the impulse), Psi (angle of 
                         approach) and alpha (angle that defines the direction of the 
                         impulse). The results show the best direction to apply the impulse 
                         for each specific geometry of the passage, maximizing the gains or 
                         energy losses. The results show, as an example, that an angle 
                         alpha near 20 degrees gives the best solution to maximize the 
                         energy gains for the situation where the periapsis distance is 1.1 
                         Moon's radius and Psi = 90 degrees. This value goes to near -20 
                         degrees when Psi = 270 degrees. In the case of maximizing the 
                         energy losses, two families with impulses against the direction of 
                         the spacecraft motion are found to be the best solutions. 
                         Conditions where the impulse generates a capture around the Moon 
                         or a collision are also mapped. For values larger than 1.1 Moon's 
                         radius for the periapsis distance, the angle that maximizes the 
                         energy variation increases. Empirical analytical equations are 
                         obtained that express the energy variation as a function of the 
                         angle of approach, which replaces well-known equations obtained 
                         from the two-body approximation.",
                  doi = "10.1016/j.asr.2015.04.016",
                  url = "http://dx.doi.org/10.1016/j.asr.2015.04.016",
                 issn = "0273-1177 and 1879-1948",
             language = "en",
           targetfile = "ferreira_a numerical.pdf",
        urlaccessdate = "03 dez. 2020"