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The history of the lunar orbit
A method of calculating the past states of the earth-moon system is developed. The method is based on the existence of three distinct time scales for dynamical change. The short time scale isExpand
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Origin of chaos in the Prometheus-Pandora system
We demonstrate that the chaotic orbits of Prometheus and Pandora are due to interactions associated with the 121:118 mean motion resonance. Differential precession splits this resonance into aExpand
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Towards a theory for the uranian rings
Interparticle collisions, radiation drag and differential precession all tend to disrupt the rings of Uranus. The first two effects lead to radial spreading which would disrupt a free ring in ≲108Expand
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Sharp edges of planetary rings
The ring systems of Saturn and Uranus exhibit several sharp edges across which the optical depth drops from order unity to essentially zero. At least two and perhaps all of these features areExpand
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Elastic ice shells of synchronous moons: Implications for cracks on Europa and non-synchronous rotation of Titan
A number of synchronous moons are thought to harbor water oceans beneath their outer ice shells. A subsurface ocean frictionally decouples the shell from the interior. This has led to proposals thatExpand
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Quasar absorption lines
" Analyzing a spectrum is exactly like doing a crossword puzzle, but when you get through with it, you call the answer research. " – Henry Norris Russell. The absorption lines observed in quasarExpand
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Single-Sided Shepherding
Abstract Narrow ringlets are observed to form at isolated Lindblad resonances in recent simulations (J. Hanninen and H. Salo, Icarus 108, 325-346 (1994) and 117, 435-438 (1995)). Our remarks areExpand
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Rotation of the Sun
Dicke has interpreted his recent measurement of the sun's oblateness as implying a fast (1.8-day period) rotation of the solar radiative interior. We find that differentially rotating solar models,Expand
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Magnetic focusing in the Sco X-1 radio source
There has been much theoretical discussion of the confinement of the radio jets associated with extragalactic radio sources1. There are now several examples of sources where the minimum pressureExpand
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Chaotic Motions of F-Ring Shepherds
Recent HST images of the Saturnian satellites Prometheus and Pandora show that their longitudes deviate from predictions of ephemerides based on Voyager images. Currently Prometheus is lagging andExpand
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