A Numerical Survey of Transient Co-orbitals of the Terrestrial Planets

We study the dynamical evolution of asteroid 2002 AA 29 . This object moves in the co-orbital region of the Earth and is the first known asteroid which experiences We distinguish a few moments in time crucial for understanding its dynamics. Near 2400 and 2500 this object will be close to going through the maxima of the averaged disturbing function and it will either change its co-orbital regime by transition from the HS into QS state, or leave the librating mode. These approaches generate instability in the motion of 2002 AA 29 . By means of 66 observations, covering a two-year interval, we extend the analysis of the long term evolution of this object presented by Connors et al. (2002) and Brasser et al. (2004a). Our analysis is based on a sample of 100 cloned orbits. We show that the motion of 2002 AA 29 is predictable in the time interval [−2600, 7100] and outside of this interval the past and future orbital history can be studied using statistical methods.

Section: Long-term Evolutionsupporting

confidence: 90%

Section: Accepted M Manuscriptmentioning

confidence: 99%

2002 AA29: Earth's recurrent quasi-satellite?

Wajer¹

2009

“…Moreover, several objects which move (or will be moving in the future) on compound HS-QS and TP-QS orbits were recognized inside the Earth's co-orbital region 1 (see eg. Wiegert et al (1998); Namouni et al (1999); Christou (2000); Brasser et al (2004a); Wajer (2008b)). Kinoshita and Nakai (2007) found that Jupiter has four quasi-satellites at present: two asteroids, 2001 QQ 199 and2004 AE 9 , as well as two comets, P/2002 AR 2 LIN-EAR and P/2003 WC 7 LINEAR-CATALINA.…”

Section: Introductionmentioning

confidence: 99%

“…Quasi-satellites move outside of the planet's Hill sphere at the mean distance from the associated planet of the order of O(e), where e is the eccentricity of the object. For sufficiently large values of eccentricity and/or high enough inclination transitions between QS and HS (or TP) orbits are possible, and there can exist compound orbits which are unions of the HS (or TP) and QS orbits (Namouni, 1999;Namouni et al, 1999;Christou, 2000;Brasser et al, 2004a) So far quasi-satellites have been found for Venus, Earth and Jupiter. Venus currently has one temporary quasi-satellite object 2002 VE 68 and also one compound HS-QS orbiter (Brasser et al, 2004a).…”

Section: Introductionmentioning

confidence: 99%

Dynamical evolution of Earth’s quasi-satellites: 2004 GU9 and 2006 FV35

Wajer

2010

“…Any primordial Saturn and Uranus Trojans would have been subsequently lost through planetary perturbations (Nesvorný and Dones, 2002;Dvorak et al, 2010;Hou et al, 2014), with the known Uranus Trojans thought to be temporarily captured from among the Centaurs (Alexandersen et al, 2013;de la Fuente Marcos and de la Fuente Marcos, 2014). Some hypothetical Trojans of Earth would have been long-term stable, with the situation at Venus being less clear (Tabachnik and Evans, 2000;Cuk et al, 2012;Marzari and Scholl, 2013); however, so far only temporary coorbitals of these planets are known (Christou, 2000;Christou and Asher, 2011;Connors et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

Yarkovsky-driven spreading of the Eureka family of Mars Trojans

Ćuk

Christou

Hamilton

2015

Out of nine known stable Mars Trojans, seven appear to be members of an orbital grouping including the largest Trojan, Eureka. In order to test if this could be a genetic family, we simulated the long term evolution of a tight orbital cluster centered on Eureka. We explored two cases: cluster dispersal through planetary gravity alone over 1 Gyr, and a 1 Gyr evolution due to both gravity and the Yarkovsky effect. We find that the dispersal of the cluster in eccentricity is primarily due to dynamical chaos, while the inclinations and libration amplitudes are primarily changed by the Yarkovsky effect. Current distribution of the cluster members orbits are indicative of an initially tight orbital grouping that was affected by a negative acceleration (i.e. one against the orbital motion) consistent with the thermal Yarkovsky effect. We conclude that the cluster is a genetic family formed either in a collision or through multiple rotational fissions. The cluster's age is on the order of 1 Gyr, and its long-term orbital evolution is likely dominated by the seasonal, rather than diurnal, Yarkovsky effect. If confirmed, Gyr-scale dominance of the seasonal Yarkovsky effect may indicate suppression of the diurnal Yarkovsky drift by the related YORP effect. Further study of Mars Trojans is essential for understanding the long-term orbital and rotational dynamics of small bodies in the absence of frequent collisions.