Robin Canup - Academia.edu (original) (raw)

Papers by Robin Canup

Nature, 2000

The Moon is generally believed to have formed from the debris disk created by a large body collid... more The Moon is generally believed to have formed from the debris disk created by a large body colliding with the early Earth. Recent models of this process predict that the orbit of the newly formed Moon should be in, or very near, the Earth's equatorial plane. This prediction, however, is at odds with the known history of the lunar orbit: the orbit is currently expanding, but can be traced back in time to reveal that, when the Moon formed, its orbital inclination relative to the Earth's equator was I approximately = 10 degrees. The cause of this initial inclination has been a mystery for over 30 years, as most dynamical processes (such as those that act to flatten Saturn's rings) will tend to decrease orbital inclinations. Here we show that the Moon's substantial orbital inclination is probably a natural result of its formation from an impact-generated disk. The mechanism involves a gravitational resonance between the Moon and accretion-disk material, which can increase orbital inclinations up to approximately 15 degrees.

Thesis University of Colorado at Boulder 1995 Source Dissertation Abstracts International Volume 56 09 Section B Page 4935, 1995

Lunar and Planetary Science Conference, Mar 1, 2001

Bulletin of the American Astronomical Society, May 1, 2004

We consider a scenario in which the Galilean satellites form within a circumplanetary accretion d... more We consider a scenario in which the Galilean satellites form within a circumplanetary accretion disk produced during the end stages of gas accretion onto Jupiter. In Canup and Ward (2002), we identified disk conditions compatible with three main constraints on satellite formation: 1) disk temperatures low enough for ices in the general region of Ganymede and Callisto, 2) satellite accretion

To avoid accretion of substantial hydrogen, it is likely that the final stage of Uranus formation... more To avoid accretion of substantial hydrogen, it is likely that the final stage of Uranus formation post-dated the bulk of the solar nebula. This renders it unlikely that its satellite system formed from a hydrogen-rich circumplanetary disk, and suggests it might instead be a by-product of a giant impact. Indeed, the 97 degree obliquity of Uranus is often cited as

The satellite systems of Jupiter and Saturn are thought to have formed from circumplanetary disks... more The satellite systems of Jupiter and Saturn are thought to have formed from circumplanetary disks surrounding these planets that developed during the accretion of the planets themselves. Early models assumed that the mass of the disk could be estimated by augmenting the satellite system to roughly solar composition. When translated to a circumplanetary environment, this predicts a disk in which

The Jovian and Saturnian regular satellites are believed to have accreted within circumplanetary ... more The Jovian and Saturnian regular satellites are believed to have accreted within circumplanetary disks of gas and solids. Such disks probably existed during the final stages of gas planet accretion, because gas inflowing from solar orbit that contained too much angular momentum to fall directly onto the planet would have instead flowed into circumplanetary orbit. As a circumplanetary gas disk

The Astrophysical Journal, 2006