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

  title={How primordial is the structure of comet 67P? - Combined collisional and dynamical models suggest a late formation},
  author={Martin Jutzi and W. Benz and Anastasia Toliou and Alessandro Morbidelli and Ramon Brasser},
  journal={Astronomy and Astrophysics},
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. We investigate the effects of collisions on a comet with a structure like 67P/Churyumov-Gerasimenko (67P). We develop scaling laws for the critical specific impact energies Q reshape required for a significant shape alteration. These are then used in simulations of the combined dynamical and… 

Catastrophic disruptions as the origin of bilobate comets

Several comets observed at close range have bilobate shapes1, including comet 67P/Churyumov–Gerasimenko (67P/C–G), which was imaged by the European Space Agency’s Rosetta mission2,3. Bilobate comets

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)

A gas-phase primordial origin of O2 in comet 67P/Churyumov-Gerasimenko

Recent observations made by the Rosetta/ROSINA instrument have detected molecular oxygen in the coma of comet 67P/Churyumov-Gerasimenko with abundances at the 1–10 per cent level relative to H2O.

On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko

Two major findings of the Rosetta mission on the composition of comet 67P/Churyumov-Gerasimenko are discussed and their context is put in the context of what the authors know from other comets and solar system objects.

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

The Effect of Cosmic Rays on Cometary Nuclei. II. Impact on Ice Composition and Structure

Since their formation in the protosolar nebula some ∼4.5 billion years ago, comets are in storage in cold distant regions of the solar system, the Kuiper Belt/scattered disk or Oort Cloud. Therefore,

Forming a Churyumov-Gerasimenko–like comet by sublimation

The Rosetta spacecraft, which was sent to the comet 67P/Churyumov-Gerasimenko, collected data of the nucleus revealing its peculiar bi-lobed shape. A discussion about whether the shape is primordial

Kuiper belt: Formation and evolution

Comets and Planetesimal Formation

In this chapter, we review the processes involved in the formation of planetesimals and comets. We will start with a description of the physics of dust grain growth and how this is mediated by



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

The hypothesis that nuclei formed by collisional coagulation—either out of cometesimals accreting in the early solar system or, alternatively, out of comparable-sized debris clumps paired in the aftermath of major collisions—is advanced.

Comet 67P/Churyumov-Gerasimenko: Constraints on its origin from OSIRIS observations

Context. One of the main aims of the ESA Rosetta mission is to study the origin of the solar system by exploring comet 67P/Churyumov-Gerasimenko at close range. Aims. In this paper we discuss the

The primordial nucleus of comet 67P/Churyumov-Gerasimenko

We investigate the formation and evolution of comet nuclei and other trans-Neptunian objects (TNOs) in the solar nebula and primordial disk prior to the giant planet orbit instability foreseen by the

Fission and reconfiguration of bilobate comets as revealed by 67P/Churyumov-Gerasimenko.

The reconfiguration process suggested here would preferentially decimate comet nuclei during migration to the inner solar system, perhaps explaining this lack of a substantial cometary flux.

Two independent and primitive envelopes of the bilobate nucleus of comet 67P

The notable structural similarities between the two lobes of comet 67P/Churyumov–Gerasimenko indicate that the early-forming cometesimals experienced similar primordial stratified accretion, even though they formed independently.

Planetesimal formation by sweep-up: how the bouncing barrier can be beneficial to growth

Context. The formation of planetesimals is often accredited to the collisional sticking of dust grains. The exact process is unknown, as collisions between larger aggregates tend to lead to

Comets as collisional fragments of a primordial planetesimal disk

The Rosetta mission and its exquisite measurements have revived the debate on whether comets are pristine planetesimals or collisionally evolved objects. We investigate the collisional evolution

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


Recent years have shown many advances in our knowledge of the collisional evolution of protoplanetary dust. Based on a variety of dust-collision experiments in the laboratory, our view of the growth