86 citations · 752 across the 40 of their papers we have counts for
40 papers
Minimal Local Simulation Foundations for LLM- and VLM-Driven Agents in 2D and 3D Environments
Ryuki Hyodo
Large language models (LLMs) and vision-language models (VLMs) are expanding the range of behaviors that can be represented in agent-based simulations, but many contemporary platfo…
Numerical Simulations of Hypervelocity Micrometeoroid Impacts: Rocky Impactors onto Icy Targets and the Role of Porosity
Ryuki Hyodo, Shigeru Wakita, Brandon C. Johnson
In the outer Solar System, for example in the Saturnian system, a planet's strong gravity attracts micrometeoroids and generates hypervelocity impacts on bodies such as rings and s…
Dynamical Evolution of V-Shaped Collision Debris
Ryuki Hyodo, Naoya Torii
Catastrophic collisions between proto-satellites have been proposed as a possible origin of Saturn's rings. This argument relies on the concept of the equivalent circular orbit. He…
Ring formation around giant planets by tidal disruption of a single passing large Kuiper belt object II: The dynamical fate of tidal fragments
Naoya Torii, Shigeru Ida, Ryuki Hyodo
Planetary rings are ubiquitous structure in our Solar System, but their formation mechanisms remain under debate. One of the proposed scenarios is the tidal disruption of a nearby…
Ringed versus Ringless Worlds: How Poynting-Robertson Drag Shapes Rings across the Solar System
Ryuki Hyodo, Shigeru Ida
Planetary rings are not only ubiquitous around the giant planets in the outer Solar System, but have also been discovered around several small distant bodies. In contrast, no rings…
Mixing model of Phobos' bulk elemental composition for the determination of its origin: Multivariate analysis of MMX/MEGANE data
Kaori Hirata, Tomohiro Usui, Ryuki Hyodo +6
The formation process of the two Martian moons, Phobos and Deimos, is still debated with two main competing hypotheses: the capture of an asteroid or a giant impact onto Mars. In o…
Exploring the recycling model of Phobos formation: rubble-pile satellites
Gustavo Madeira, Sebastien Charnoz, Yun Zhang +4
Phobos is the target of the return sample mission Martian Moons eXploration by JAXA that will analyze in great details the physical and compositional properties of the satellite fr…
Dynamical origin of Dimorphos from fast spinning Didymos
Gustavo Madeira, Sebastien Charnoz, Ryuki Hyodo
Didymos is a binary near-Earth asteroid. It is the target of the DART and HERA space missions. The primary body, Didymos, rotates close to the spin at which it is expected to shed…
Modeling the Evolution of Silicate/Volatile Accretion Discs around White Dwarfs
Ayaka Okuya, Shigeru Ida, Ryuki Hyodo +1
A growing number of debris discs have been detected around metal-polluted white dwarfs. They are thought to be originated from tidally disrupted exoplanetary bodies and responsible…
Giga-Year Dynamical Evolution of Particles Around Mars
Yuying Liang, Ryuki Hyodo
Particles of various sizes can exist around Mars. The orbits of large particles are mainly governed by Martian gravity, while those of small particles could be significantly affect…
Formation of moons and equatorial ridge around top-shaped asteroids after surface landslide
Ryuki Hyodo, Keisuke Sugiura
Top-shaped asteroids have been observed among near-Earth asteroids. About half of them are reported to have moons (on the order of wt.\% of the top-shaped primary) and many…
Challenges in forming Phobos and Deimos directly from a splitting of an ancestral single moon
Ryuki Hyodo, Hidenori Genda, Ryosuke Sekiguchi +2
The origin and evolution of Martian moons have been intensively debated in recent years. It is proposed that Phobos and Deimos may originate directly from a splitting of an ancestr…
A "no-drift" runaway pile-up of pebbles in protoplanetary disks II. Characteristics of the resulting planetesimal belt
Ryuki Hyodo, Shigeru Ida, Tristan Guillot
Forming planetesimals from pebbles is a major challenge in our current understanding of planet formation. In a protoplanetary disk, pebbles drift inward near the disk midplane via…
Asteroid Flyby Cycler Trajectory Design Using Deep Neural Networks
Naoya Ozaki, Kanta Yanagida, Takuya Chikazawa +3
Asteroid exploration has been attracting more attention in recent years. Nevertheless, we have just visited tens of asteroids while we have discovered more than one million bodies.…
Tidal evolution of the eccentric moon around dwarf planet (225088) Gonggong
Sota Arakawa, Ryuki Hyodo, Daigo Shoji +1
Recent astronomical observations revealed that (225088) Gonggong, a 1000-km-sized trans-Neptunian dwarf planet, hosts an eccentric satellite, Xiangliu, with an eccentricity of appr…
Forming pressure-traps at the snow-line to isolate isotopic reservoirs in the absence of a planet
Sébastien Charnoz, Guillaume Avice, Ryuki Hyodo +2
Pressure maxima are regions in protoplanetary disks where pebbles can be trapped because of the local absence of pressure gradient. These regions could be ideal places to form plan…
Tidal pull of the Earth strips the proto-Moon of its volatiles
S. Charnoz, P. A. Sossi, Y-N Lee +7
Prevailing models for the formation of the Moon invoke a giant impact between a planetary embryo and the proto-Earth \citep{Canup_2004, Cuk_Stewart_2012}. Despite similarities in t…
SPH Simulations for Shape Deformation of Rubble-Pile Asteroids Through Spinup: The Challenge for Making Top-Shaped Asteroids Ryugu and Bennu
Keisuke Sugiura, Hiroshi Kobayashi, Sei-ichiro Watanabe +3
Asteroid Ryugu and asteroid Bennu, which were recently visited by spacecraft Hayabusa2 and OSIRIS-REx, respectively, are spinning top-shaped rubble piles. Other axisymmetric top-sh…
Erosion and accretion by cratering impacts on rocky and icy bodies
Ryuki Hyodo, Hidenori Genda
During planet formation, numerous small impacting bodies result in cratering impacts on large target bodies. A fraction of the target surface is eroded, while a fraction of the imp…
A "no-drift" runaway pile-up of pebbles in protoplanetary disks in which midplane turbulence increases with radius
Ryuki Hyodo, Shigeru Ida, Tristan Guillot
A notable challenge of planet formation is to find a path to directly form planetesimals from small particles. We aim to understand how drifting pebbles pile up in a protoplanetary…
Planetesimal formation around the snow line. II. Dust or pebbles?
Ryuki Hyodo, Tristan Guillot, Shigeru Ida +2
Around the snow line, icy pebbles and silicate dust may locally pile-up and form icy and rocky planetesimals via streaming instability and/or gravitational instability. We perform…
Planetesimal formation around the snow line: I. Monte Carlo simulations of silicate dust pile-up in a turbulent disk
Shigeru Ida, Tristan Guillot, Ryuki Hyodo +2
Context: The formation of rocky planetesimals is a long-standing problem in planet formation theory. One of the possibilities is that it results from gravitational instability as a…
Modification of the composition and density of Mercury from late accretion
Ryuki Hyodo, Hidenori Genda, Ramon Brasser
Late accretion is a process that strongly modulated surface geomorphic and geochemical features of Mercury. Yet, the fate of the impactors and their effects on Mercury's surface th…
Escape and accretion by cratering impacts: Formulation of scaling relations for high-speed ejecta
Ryuki Hyodo, Hidenori Genda
Numerous small bodies inevitably lead to cratering impacts on large planetary bodies during planet formation and evolution. As a consequence of these small impacts, a fraction of t…