搜索结果: 16-30 共查到“知识库 行星物理学”相关记录322条 . 查询时间(4.767 秒)
NG：FeO的超高压相变及其对系外行星内部的启示（图）
FeO 超高压相变 系外行星内部
2023/1/16
在过去数十年里，数以千计的系外行星被发现，其中包括许多比地球体积更大、内部温度压力更高的岩质系外行星。目前，大多数描述这些岩质系外行星内部成分的模型都是基于地球分层结构的缩放版本，即由硅酸盐为主的幔包围着铁核。虽然这些模型便于我们理解岩质系外行星的内部结构和组成，却忽略了大型岩质系外行星（比地球体积或质量大）中极端温度和压力条件所造成的物质属性变化。例如，Unterborn and Panero ...
ILLUMINATION INVARIANT CHANGE DETECTION (IICD): FROM EARTH TO MARS
Illumination Planetary Surface Change Detection Phase Correlatio Saliency Active Contour
2018/5/15
Multi-temporal Earth Observation and Mars orbital imagery data with frequent repeat coverage provide great capability for planetary surface change detection. When comparing two images taken at differe...
Interactive evolution of multiple water-ice reservoirs on Mars: Insights from hydrogen isotope compositions
Mars water ice isotope atmospheric escape
2017/4/10
Remote sensing data from orbiter missions have proposed that ground ice may currently exist on Mars, although the
volume is still uncertain. Recent analyses of Martian meteorites have suggested that ...
COUPLED SPIN AND SHAPE EVOLUTION OF SMALL RUBBLE-PILE ASTEROIDS:SELF-LIMITATION OF THE YORP EFFECT
methods numerical–minor planets,asteroids general
2015/12/25
We present the first self-consistent simulations of the coupled spin-shape evolution of small gravitational aggregates under the influence of the YORP effect. Because of YORP's sensitivity to surface ...
Numerical simulations of collisional disruption of rotating gravitational aggregates:Dependence on material properties
Asteroids Planetesimals Dynamics N-body simulations Collisional physics
2015/12/25
Our knowledge of the strengths of small bodies in the Solar System is limited by our poor understanding of their internal structures, and this, in turn, clouds our understanding of the formation and e...
Selective sampling during catastrophic disruption:Mapping the location of reaccumulated fragments in the original parent body
Asteroids Collisions Internal structure Gravitational reaccumulations
2015/12/25
In this paper, we simulate numerically the catastrophic disruption of a large asteroid as a result of a collision with a smaller projectile and the subsequent reaccumulation of fragments as a result o...
Low-speed impact simulations into regolith in support of asteroid sampling mechanism design I:Comparison with 1-g experiments
Asteroids Surfaces Collisional physics Granular material Sampling mechanism Geological processes Regoliths
2015/12/25
This study is carried out in the framework of sample-return missions to asteroids that use a low-speed projectile as the primary component of its sampling mechanism (e.g., JAXA’s Hayabusa and Hayabusa...
Numerical predictions of surface effects during the 2029 close approach of Asteroid 99942 Apophis
Asteroids,dynamics Asteroids, surfaces Near-Earth objects Regoliths Tides,solid body
2015/12/25
Asteroid (99942) Apophis’ close approach in 2029 will be one of the most significant small-body encounter events in the near future and offers a good opportunity for in situ exploration to determine t...
The Brazil nut effect and its application to asteroids
methods:numerical comets:general minor planets,asteroids:general
2015/12/25
Out of the handful of asteroids that have been imaged, some have distributions of blocks that are not easily explained. In this paper, we investigate the possibility that seismic shaking leads to the ...
Numerically simulating impact disruptions of cohesive glass bead agglomerates using the soft-sphere discrete element method
Asteroids, Surfaces Collisional physics Geological processes Regoliths
2015/12/25
We present our implementation of cohesion in the parallel N-body code pkdgrav in order to model small bodies that are not fully monolithic but that have at least some degree of cohesion. Small bodies ...
ROTATION-DEPENDENT CATASTROPHIC DISRUPTION OF GRAVITATIONAL AGGREGATES
minor planets asteroids:general planets and satellites:formation planets and satellites:physical evolution
2015/12/25
We carry out a systematic exploration of the effect of pre-impact rotation on the outcomes of low-speed collisions between planetesimals modeled as gravitational aggregates. We use pkdgrav, a cosmolog...
Collision and gravitational reaccumulation:Possible formation mechanism of the asteroid Itokawa
gravitation methods:numerical minor planets asteroids:general minor planets asteroids:individual:Itokawa
2015/12/25
Aims: We investigate the possibility that the observed sea-otter shape of the asteroid Itokawa, associated with the presence of big boulders on its surface, originates from the reaccumulation process ...
Spin-up of rubble-pile asteroids:Disruption,satellite formation,and equilibrium shapes
Asteroid, Dynamics Rotational dynamics Satellites,Dynamics
2015/12/25
We present results from numerical experiments testing the behavior of cohesionless gravitational aggregates experiencing a gradual increase of angular momentum. The test bodies used in these numerical...
N-body simulations of cohesion in dense planetary rings:A study of cohesion parameters
Planetary rings Saturn, Rings Tides, Solid body Ices, Mechanical properties Collisional physics
2015/12/25
We present results from a large suite of simulations of Saturn’s dense A and B rings using a new model of particle sticking in local simulations (Perrine, R.P., Richardson, D.C., Scheeres, D.J. [2011]...
A comparison between rubble-pile and monolithic targets in impact simulations:Application to asteroid satellites and family size distributions
Asteroids Collisional physics Impact processes Satellites, General
2015/12/25
Collisions are a fundamental process in the creation of asteroid families and in satellite formation. For this reason, understanding the outcome of impacts is fundamental to the accurate modeling of t...