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tokens: the stability of the orbits in the sense of keeping them within a well-defined section of the available orbital parameter space, Fig. 1 indicates that the eccentricity may eventually reach values that lead the aphelion closer to the Earth–Moon system, perhaps triggering an impact or an ejection from NEA parameter space. Conversely, a larger value of the eccentricity may lead to a shorter perihelion and an eventual collision with the Sun or an ejection from the Solar system or into its outskirts. In our case, the value of the aphelion distance, that oscillates between those of the semimajor axes of Venus and the Earth, can become as high as 1.02 au (see Fig. 6 , right-hand panel), opening the door to eventual impacts on our planet if one of the nodes reaches aphelion (see also Ribeiro et al. 2016 ). Members of the Atira population can eventually become impactors as a result of the complex orbital evolution discussed here and in the event of an impact, they will most probably come from out of the Sun’s glare. 3.3.2 Vatira evolution The evolution of 2019 AQ 3 shown in Fig. 1 initially leads to brief periods (in thick red/grey) in which the aphelion distance of 2019 AQ 3 , Q 0.718 au i.e. 2019 AQ 3 , an Atira, becomes a transient Vatira. This opens the door to transitions between the two dynamical classes. In fact, the dynamical context that keeps 2019 AQ 3 in a chaotic but relatively stable state may be effective in enabling a dynamical pathway to go from the Atira orbital realm into the Vatira one as shown by the evolution after about 3.5 Myr into the future. The progressive reduction in the value of the semimajor axis eventually leads to a transition from the Atira population into the Vatiras that avoid encounters with Venus altogether. Fig. 6 shows that transitions to and from the Vatira orbital realm are also possible well away from the nominal orbit. Our calculations show that a combination of secular evolution and eventual close encounters with Venus triggers the transitions. Atiras do not cross the orbit of the Earth–Moon system and Vatiras do not cross the orbit of Venus; both Atiras and Vatiras define disjoint subsets. Atiras can impact on Venus, Vatiras cannot; therefore and although the members of both dynamical classes interact with Venus, they do it quite differently. We may now argue that the distinctive dynamical property of putative, long-term stable Vatiras is that they must be virtually and dynamically detached from Venus. This implies a robust difference between the dynamical behaviour of hypothetically stable Atiras, such as those discussed by Ribeiro et al. ( 2016 ), and stable Vatiras. In general, Atiras may still experience close encounters with Venus, Vatiras cannot. When the Lidov–Kozai resonance is at work, in addition to avoiding close encounters with Venus at aphelion, close encounters with Mercury at perihelion are also reduced, but the orbit of Mercury is far more eccentric (0.21) and inclined (70) than that of