Seeding the Formation of Mercurys: An Iron-sensitive Bouncing Barrier in Disk Magnetic Fields

Abstract

The inner part of protoplanetary disks can be threaded by strong magnetic fields. In laboratory levitation experiments, we study how magnetic fields up to 7 mT influence the aggregation of dust by observing the self-consistent collisional evolution of particle ensembles. As dust samples we use mixtures of iron and quartz in different ratios. Without magnetic fields, particles in all samples grow into a bouncing barrier. These aggregates reversibly form larger clusters in the presence of magnetic fields. The size of these clusters depends on the strength of the magnetic field and the ratio between iron and quartz. The clustering increases the size of the largest entities by a factor of a few. If planetesimal formation is sensitive to the size of the largest aggregates, e.g., relying on streaming instabilities, then planetesimals will preferentially grow iron-rich in the inner region of protoplanetary disks. This might explain the iron gradient in the solar system and the formation of dense Mercury-like planets.

References in corpus (31)

• Streaming Instabilities in Protoplanetary Disks
• The evaporation valley in the Kepler planets
• The outcome of protoplanetary dust growth: pebbles, boulders, or planetesimals? II. Introducing the bouncing barrier
• Masses, Radii, and Orbits of Small Kepler Planets: The Transition from Gaseous to Rocky Planets
• Dynamics of Solids in the Midplane of Protoplanetary Disks: Implications for Planetesimal Formation
• The Mass and Size Distribution of Planetesimals Formed by the Streaming Instability. I. The Role of Self-Gravity
• Compositional imprints in density-distance-time: a rocky composition for close-in low-mass exoplanets from the location of the valley of evaporation
• Magnetic fields in protoplanetary disks
• Can dust coagulation trigger streaming instability?
• The Physics of Protoplanetesimal Dust Agglomerates. III. Compaction in Multiple Collisions
• Direct magnetic field detection in the innermost regions of an accretion disc
• The Roche limit for close-orbiting planets: Minimum density, composition constraints, and application to the 4.2-hour planet KOI 1843.03
• An Earth-sized exoplanet with a Mercury-like composition
• Equilibrium Condensation from Chondritic Porous IDP Enriched Vapor: Implications for Mercury and Enstatite Chondrite Origins
• Photophoretic separation of metals and silicates: the formation of Mercury like planets and metal depletion in chondrites
• Magnetic Aggregation I: Aggregation Dynamics and Numerical Modelling
• K2-106, a system containing a metal-rich planet and a planet of lower density
• Porosities of Protoplanetary Dust Agglomerates from Collision Experiments
• Experimental Study on Bouncing Barriers in Protoplanetary Disks
• Fossil magnetic field of accretion disks of young stars
• K2-66b and K2-106b: Two extremely hot sub-Neptune-size planets with high densities
• Magnetic fields in protoplanetary disks: from MHD simulations to ALMA observations
• Failed Growth at the Bouncing Barrier in Planetesimal Formation
• Self-sustained Levitation of Dust Aggregate Ensembles by Temperature Gradient Induced Overpressures
• Crossing barriers in planetesimal formation: The growth of mm-dust aggregates with large constituent grains
• Magnetic fields in circumstellar disks: The potential of Zeeman observations
• Is There a Temperature Limit in Planet Formation at 1000 K?
• Terrestrial Planet Formation: Constraining the Formation of Mercury
• Growing into and out of the bouncing barrier in planetesimal formation
• Effects of photophoresis on the dust distribution in a 3D protoplanetary disc
• Explaining Mercury's Density through Magnetic Erosion

Cited by in corpus (25)

• Observations of Protoplanetary Disk Structures
• Understanding planet formation using microgravity experiments
• Nucleation and growth of iron pebbles explains the formation of iron-rich planets akin to Mercury
• HD 23472: A multi-planetary system with three super-Earths and two potential super-Mercuries
• The HD 137496 system: A dense, hot super-Mercury and a cold Jupiter
• Forming super-Mercuries: The role of stellar abundances
• Composition and Size Dependent Sorting in Preplanetary Growth: Seeding the Formation of Mercury-like Planets
• A Smoking Gun for Planetesimal Formation: Charge Driven Growth into a New Size Range
• Dynamical avenues for Mercury's origin II: in-situ formation in the inner terrestrial disk
• TOI-1075 b: A Dense, Massive, Ultra-Short Period Hot Super-Earth Straddling the Radius Gap
• The Exosphere as a Boundary: Origin and Evolution of Airless Bodies in the Inner Solar System and Beyond Including Planets with Silicate Atmospheres
• The growth of super-large pre-planetary pebbles to an impact erosion limit
• Aggregation of Sub-mm Particles in Strong Electric Fields under Microgravity Conditions
• Explaining Mercury via a single giant impact is highly unlikely
• Mercury's formation within the Early Instability Scenario
• Onset of planet formation in the warm inner disk -- Colliding dust aggregates at high temperatures
• Forbidden planetesimals
• The Curie line in protoplanetary disks and the formation of Mercury-like planets
• Unknotting of quasi-two-dimensional ferrogranular networks by in-plane homogeneous magnetic fields
• Selective Aggregation Experiments on Planetesimal Formation and Mercury-Like Planets
• Building Earth with pebbles made of chondritic components
• Variable refractory lithophile element compositions of planetary building blocks: insights from components of enstatite chondrites
• Ionizing Protoplanetary Disks in Pebble Collisions
• Origins of Mercury's Big Heart of Iron: Exploring Pathways to Form High Core Mass Fraction (CMF) Planets via N-body Simulations
• Accretion disk's magnetic field controlled the composition of the terrestrial planets