The shape and structure of cometary nuclei as a result of low-velocity accretion

  title={The shape and structure of cometary nuclei as a result of low-velocity accretion},
  author={Martin Jutzi and Erik Asphaug},
  pages={1355 - 1358}
Collisions give comets their shape The shape and structure of comets are relicts of collision processes from long ago. Despite recent and ongoing spacecraft missions that offer direct measurements of cometary nuclei, it is difficult to test what is important in comet shaping. Jutzi and Asphaug ran ∼100 three-dimensional collision simulations across a wide range of target and impactor masses and trajectories. Slow and less violent collisions produced the layering and bi-lobed shapes of actual… 

Evidence for geologic processes on comets

Spacecraft missions have resolved the nuclei of six periodic comets and revealed a set of geologically intriguing and active small bodies. The shapes of these cometary nuclei are dominantly bilobate

The shape and structure of small asteroids as a result of sub-catastrophic collisions

  • M. Jutzi
  • Physics, Geology
    Planetary and Space Science
  • 2019

The Formation of Bilobate Comet Shapes through Sublimative Torques

The results suggest that the bilobate shapes of observed comets developed recently in their history, rather than during solar system formation or collisions during planet migration and residency in the trans-Neptunian population.

Origin and Evolution of Cometary Nuclei

One of the key goals of the Rosetta mission was to understand how, where and when comets formed in our solar system. There are two major hypotheses for the origin of comets, both pre-Rosetta: (1)

How primordial is the structure of comet 67P? - Combined collisional and dynamical models suggest a late formation

Context. There is an active debate about whether the properties of comets as observed today are primordial or, alternatively, if they are a result of collisional evolution or other processes. Aims.

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The processes that led to the formation of the planetary bodies in the Solar system are still not fully understood. Using the results obtained with the comprehensive suite of instruments onboard the

Shape evolution of cometary nuclei via anisotropic mass loss

Context. Breathtaking imagery recorded during the European Space Agency Rosetta mission confirmed the bilobate nature of the nucleus of comet 67P/Churyumov-Gerasimenko. The peculiar appearance of the

Formation of bi-lobed shapes by sub-catastrophic collisions. A late origin of comet 67P's structure

Context. The origin of the particular shape of comet 67P/Churyumov-Gerasimenko (67P) is a topic of active research. How and when it acquired its peculiar characteristics has distinct implications on

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It is found that hit-and-run collisions likely occur more often in density-stratified bodies and across a wider range of impact angles than suggested by the most commonly used analytic approximation, which is contrary to the commonly assumed invariance of total mass, density structure, and material composition on the largest remnants of giant impacts.



Structure and density of cometary nuclei

Abstract— Understanding the nature of the cometary nucleus remains one of the major problems in solar system science. Whipple's (1950) icy conglomerate model has been very successful at explaining a

The Origin of Comets in the Solar Nebula: A Unified Model

Abstract Comets originated as icy planetesimals in the outer Solar System, as shown by dynamical studies and direct observation of objects in the Kuiper disk. Their nuclei have low strength


The Kuiper Belt is a remnant from the early solar system and its size distribution contains many important constraints that can be used to test models of planet formation and collisional evolution.

Comets and the origin of the solar system - Reading the Rosetta Stone

It is argued that, from the measured volatile abundances, comets formed at temperatures near or below about 60 K and possibly as low as about 25 K. Grains in Comet Halley were found to be of two

Direct N-body Simulations of Rubble Pile Collisions in Strong Tidal Fields: Applied to Saturn's F Ring

There is increasing evidence that many kilometer-sized bodies in the Solar System are piles of rubble bound together by gravity. We present results from a project to map the parameter space of

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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.