Orbit
With a semimajor axis of 2.5294 AU, or roughly 2.5 times the separation of the Earth from the Sun, Toutatis has a 3:1 orbital resonance with Jupiter and a near-1:4 resonance with Earth. Thus it completes one orbit around the Sun for every 4.02 annual orbits of the Earth. The gravitational perturbations caused by frequent close approaches to the terrestrial planets lead to chaotic behaviour in the orbit of Toutatis, making precise long-term predictions of its location progressively inaccurate over time. Estimates in 1993 put the Lyapunov time horizon for predictability at around 50 years, after which the uncertainty region becomes larger with each close approach to a planet. Without the perturbations from the terrestrial planets the Lyapunov time would be close to 10,000 years. The initial observations which showed its chaotic behaviour were made by Wiśniewski.
The low inclination (0.47°) of the orbit allows frequent transits, where the inner planets Mercury, Venus, Earth, and Mars can appear to cross the Sun as seen from the perspective of the asteroid. Earth did this in January 2009 and July 2012, and will also do it in July 2016 and 2020.
Read more about this topic: 4179 Toutatis
Famous quotes containing the word orbit:
“Words can have no single fixed meaning. Like wayward electrons, they can spin away from their initial orbit and enter a wider magnetic field. No one owns them or has a proprietary right to dictate how they will be used.”
—David Lehman (b. 1948)
“The Fitchburg Railroad touches the pond about a hundred rods south of where I dwell. I usually go to the village along its causeway, and am, as it were, related to society by this link. The men on the freight trains, who go over the whole length of the road, bow to me as to an old acquaintance, they pass me so often, and apparently they take me for an employee; and so I am. I too would fain be a track-repairer somewhere in the orbit of the earth.”
—Henry David Thoreau (1817–1862)
““To my thinking” boomed the Professor, begging the question as usual, “the greatest triumph of the human mind was the calculation of Neptune from the observed vagaries of the orbit of Uranus.”
“And yours,” said the P.B.”
—Samuel Beckett (1906–1989)