Evidence for the formation of comet 67P/Churyumov-Gerasimenko through gravitational collapse of a bound clump of pebbles

Abstract

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 on-board ESA's Rosetta mission, we present evidence that comet 67P/Churyumov-Gerasimenko likely formed through the gentle gravitational collapse of a bound clump of mm-sized dust aggregates ("pebbles"), intermixed with microscopic ice particles. This formation scenario leads to a cometary make-up that is simultaneously compatible with the global porosity, homogeneity, tensile strength, thermal inertia, vertical temperature profiles, sizes and porosities of emitted dust, and the steep increase in water-vapour production rate with decreasing heliocentric distance, measured by the instruments on-board the Rosetta spacecraft and the Philae lander. Our findings suggest that the pebbles observed to be abundant in protoplanetary discs around young stars provide the building material for comets and other minor bodies.

accepted by MNRAS

References in corpus (11)

• The stickiness of micrometer-sized water-ice particles
• How to form planetesimals from mm-sized chondrules and chondrule aggregates
• Testing the theory of grain growth and fragmentation by millimeter observations of protoplanetary disks
• Comets formed in solar-nebula instabilities! -- An experimental and modeling attempt to relate the activity of comets to their formation process (corrigendum included)
• Erosion and the limits to planetesimal growth
• Formation of pebble-pile planetesimals
• Formation of bi-lobed shapes by sub-catastrophic collisions: A late origin of comet 67P/C-G's structure
• How primordial is the structure of comet 67P/C-G? Combined collisional and dynamical models suggest a late formation
• The role of pebble fragmentation in planetesimal formation I. Experimental study
• The role of pebble fragmentation in planetesimal formation II. Numerical simulations
• On the origin of inner coma structures observed by Rosetta during a diurnal rotation of comet 67P/Churyumov-Gerasimenko

Cited by in corpus (55)

• Thresholds for Particle Clumping by the Streaming Instability
• The thermal, mechanical, structural, and dielectric properties of cometary nuclei after Rosetta
• Planetesimal Population Synthesis: Pebble Flux Regulated Planetesimal Formation
• Solution to the debris disc mass problem: planetesimals are born small?
• The Orbit and Size-Frequency Distribution of Long Period Comets Observed by Pan-STARRS1
• Thermophysical evolution of planetesimals in the Primordial Disk
• Tensile Strength of Porous Dust Aggregates
• Understanding planet formation using microgravity experiments
• Debris Disc Constraints on Planetesimal Formation
• Porous Dust Particles in Protoplanetary Disks: Application to the HL Tau Disk
• High precision meteor observations with the Canadian Automated Meteor Observatory -- Data reduction pipeline and application to meteoroid mechanical strength measurements
• Modelling the water and carbon dioxide production rates of Comet 67P/Churyumov-Gerasimenko
• Formation of Comets
• Sequential giant planet formation initiated by disc substructure
• Learning about comets from the study of mass distributions and fluxes of meteoroid streams
• Thermal conductivity and coordination number of compressed dust aggregates
• Are there any pristine comets? Constraints from pebble structure
• Thermal processing of primordial pebbles in evolving protoplanetary disks
• Volatile exposures on the 67P/Churyumov-Gerasimenko nucleus
• The radial structure of planetary bodies formed by the streaming instability
• Thermal inertias of pebble-pile comet 67P/Churyumov-Gerasimenko
• Activity distribution of comet 67P/Churyumov-Gerasimenko from combined measurements of non-gravitational forces and torques
• A quantitative description of comet 67P's dust and gas production remains enigmatic
• Cometary surface dust layers built out of millimetre-scale aggregates: dependence of modelled cometary gas production on the layer transport properties
• Optical tweezers in a dusty universe
• Planetesimal formation via the streaming instability with multiple grain sizes
• Hot exozodis: cometary supply without trapping is unlikely to be the mechanism
• Comparing the reflectivity of ungrouped carbonaceous chondrites with that of short period comets like 2P/Encke
• Sub-mm/mm optical properties of real protoplanetary matter derived from Rosetta/MIRO observations of comet 67P
• Polydisperse Formation of Planetesimals: The dust size distribution in clumps
• Forbidden planetesimals
• The ice composition close to the surface of comet 67P/Churyumov-Gerasimenko
• A gas-phase primordial origin of O2 in comet 67P/Churyumov-Gerasimenko
• A method to distinguish between micro- and macro-granular surfaces of small Solar System bodies
• Destruction of eccentric planetesimals by ram pressure and erosion
• Diurnal ejection of boulder clusters on comet 67P lasting beyond 3 AU
• Laboratory Experiments on the Motion of Dense Dust Clouds
• Cometary dust collected by MIDAS on board Rosetta. I. Dust particle catalog and statistics
• Dynamics and potential origins of decimeter-sized particles around comet 67P/Churyumov-Gerasimenko
• How much large dust could be present in hot exozodiacal dust systems?
• Survivability of Amorphous Ice in Comets Depends on the Latent Heat of Crystallization of Impure Water Ice
• The footprint of cometary dust analogues: II. Morphology as a tracer of tensile strength and application to dust collection by the Rosetta spacecraft
• On the trail of a comet's tail: A particle tracking algorithm for comet 67P/Churyumov-Gerasimenko
• Revisiting sticking property of submillimetre-sized aggregates
• Constraints on the ejecting-crust activity model on comet 67P/Churyumov-Gerasimenko
• Cometary dust collected by MIDAS on board Rosetta II. Particle shape descriptors and pristineness evaluation
• The Dissolution of Planetesimals in Electrostatic Fields
• Interpebble contact radius in a comet nucleus
• Alkali phenoxides in comets
• Formation of Ryugu's parent planetesimal beyond the CO${}_2$ snow line from small pebbles: insights from thermal evolution modeling
• Detecting and analysing geomorphological structures in images of comet 67P/Churyumov-Gerasimenko using Fourier transform
• Numerical Investigation on the Compressive Behavior of Hierarchical Granular Piles
• Direct contact binary planetesimal formation from gravitational collapse
• History of the Solar Nebula from Meteorite Paleomagnetism
• A Simulation Platform for Small Solar System Bodies' Gravity Using the Einstein-Elevator