  Atira-class asteroids have aphelia greater than 0.718 au and smaller than
0.983 au. It has been found that the orbits of many of them remain relatively
stable for at least 1 Myr, but it is unclear what can make them so stable when
they cross the orbit of Venus and some may reach, in heliocentric terms, as far
as Earth's perihelion and as close as inside Mercury's perihelion. The analysis
of their orbits shows that many of them have values of the argument of
perihelion close to 0 or 180 degrees. Such an orbital arrangement means that
the nodes are located at perihelion and at aphelion, i.e. for many known
Atiras, away from the path of Venus. Here, we show that the orbits of some
Atiras are strongly affected by the Kozai-Lidov resonance, which translates
into enhanced long-term stability.
