Hsuan-Ting Lai (IANCU); Wing-Huen Ip (IANCU)
Asteroids having perihelion distance q < 1.3 AU are classified as near-Earth objects (NEOs), which are divided into different sub-groups: Vatira-class, Atira-class, Aten-class, Apollo-class, Amor-class. One of 23 known Atira-class, 2020 AV$_2$, the first Vatira (its orbits totally inside Venus' orbit) is discovered by the Twilight project of the Zwicky Transient Facility (ZTF) on January 4, 2020. Upon the discovery of the first Vatira-class asteroid, a couple of orbital studies of the short-term orbital evolution of 2020 AV$_2$ have been performed and indicated 2020 AV$_2$ was the former Atira-class asteroid before entering the orbital region of the Vatira-class asteroid (de la Fuente Marcos et al, 2020; Greenstreet, 2020). Therefore, in this present work, we performed an assessment of the long-term orbital evolution of the known Atira-class asteroids under the Yarkovsky effect by using the Mercury N-body code. In addition, we will evaluate the lifetime of Atira-class asteroids and present a preliminary assessment of the relationship of orbital dynamical evolution between Atira-class and Vatira-class asteroids.