A hit-and-run giant impact scenario

  title={A hit-and-run giant impact scenario},
  author={Andreas Reufer and Matthias M. M. Meier and W. Benz and Rainer Wieler},
Signatures of Hit-and-run Collisions
Terrestrial planets grew in a series of similar-sized collisions that swept up most of the next-largest bodies. Theia was accreted by the Earth to form the Moon according to the theory. Planetesimals
Collisions during planetary systems formation
The Moon is believed to have formed from the debris generated by a giant impact. In the canonical impact scenario it is found that the Moon forms predominantly from impactor material. In contrast,
Fate of the Runner in Hit-and-run Collisions
In similar-sized planetary collisions, a significant part of the impactor often misses the target and continues downrange. We follow the dynamical evolution of "runners" from giant impacts to
A multiple-impact origin for the Moon
The hypothesis of lunar origin by a single giant impact can explain some aspects of the Earth–Moon system. However, it is difficult to reconcile giant-impact models with the compositional similarity
Origin of the Earth and Moon
According to the giant impact hypothesis, the Moon formed from a disk created by an impact between the proto-Earth and an impactor. Three major models for this hypothesis are (a) standard model: a
N-Body Simulation of the Formation of the Earth-Moon System from a Single Giant Impact
The giant impact hypothesis is the dominant theory of how the Earth-Moon system was formed. Models have been created that can produce a disk of debris with the proper mass and composition to create
Constraints on the pre-impact orbits of Solar system giant impactors
We provide a fast method for computing constraints on impactor pre-impact orbits, applying this to the late giant impacts in the Solar System. These constraints can be used to make quick, broad
Collision Chains among the Terrestrial Planets. III. Formation of the Moon
In the canonical model of Moon formation, a Mars-sized protoplanet “Theia” collides with proto-Earth at close to their mutual escape velocity v esc and a common impact angle ∼45°. The
Collision Chains among the Terrestrial Planets. II. An Asymmetry between Earth and Venus
During the late stage of terrestrial planet formation, hit-and-run collisions are about as common as accretionary mergers, for expected velocities and angles of giant impacts. Average hit-and-runs


Hit-and-run planetary collisions
It is shown that colliding planets do not simply merge, as is commonly assumed, and in many cases, the smaller planet escapes from the collision highly deformed, spun up, depressurized from equilibrium, stripped of its outer layers, and sometimes pulled apart into a chain of diverse objects.
Origin of the Moon in a giant impact near the end of the Earth's formation
This work reports a class of impacts that yield an iron-poor Moon, as well as the current masses and angular momentum of the Earth–Moon system, and suggests that the Moon formed near the very end of Earth's accumulation.
The proto-Earth as a significant source of lunar material
Geochemical evidence continues to challenge giant impact models, which predict that the Moon formed from both proto-Earth and impactor material. Analyses of lunar samples reveal isotopic homogeneity
Evolution of a Circumterrestrial Disk and Formation of a Single Moon
Abstract We investigate the evolution of a circumterrestrial disk of debris generated by a giant impact on Earth and the dynamical characteristics of the moon accreted from the disk by using
A Scaling Relationship for Satellite-Forming Impacts
Abstract We describe a scaling relationship that can be used to characterize the results of numerical smooth particle hydrodynamic (SPH) experiments of potential satellite-forming impacts. The
Oxygen Isotopes and the Moon-Forming Giant Impact
The three oxygen isotopes (Δ17O), 16O,17O, and 18O provide no evidence that isotopic heterogeneity on the Moon was created by lunar impacts, and are consistent with the Giant Impact model.
Collisions are the core agent of planet formation. In this work, we derive an analytic description of the dynamical outcome for any collision between gravity-dominated bodies. We conduct