[Previous] | [Session 48] | [Next]
M. Connors (Athabasca U.), R. Brasser (Queen's U.), R. G. Stacey (Athabasca U.), P. Wiegert (UWO)
Neptune and Pluto share a remarkable 3:2 mean motion resonance. Neptune orbits the Sun three times for each two circuits by Pluto, and Pluto in its eccentric orbit is never at perihelion when Neptune is close. In recent years many plutinos, which share the 3:2 resonance in the outer solar system, have been discovered. We now find Earth, Venus, and Mars, to have resonant asteroids dynamically similar to the plutinos of Neptune. Earth-associated asteroids 67367, 2000 YJ11, and 2002 AV31 share many relative orbital properties, including eccentricity, with Pluto. Associated with Venus, 5381 Sekhmet and 2000 ET70 are in short-lived libration with dissimilar orbits also not similar to that of Pluto. Earth and Venus 3:2 resonant objects interact with the next outer planet, limiting their lifetimes. It is likely that such interactions also provide an injection mechanism into the resonance. In resonance with Mars are 12008 Kandrup, 1999 RO37, 2002 GO6, 2004 CN50, and four others, and these have Pluto-like and apparently primordial orbits at the inner edge of the asteroid belt. This suggests an unexpected influence of Mars on the structure of the inner belt. While plutinos have only been observed for partial orbits, these objects all have been, or soon will be, observed over a full orbital path, permitting exploration of the evolution of the resonance. In some cases we find that close approaches to the associated planet are possible, while this has generally been discounted as being involved in the origin of the Pluto resonance. Even for computational studies, these objects favor further investigations of 3:2 resonant behavior since the time scales are short. Thus, while informing us on asteroid transport in the inner solar system, ``inner plutinos" may shed light also on the outer solar system and the role of the 3:2 resonance there.
[Previous] | [Session 48] | [Next]
Bulletin of the American Astronomical Society, 36 #4
© 2004. The American Astronomical Soceity.