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Method for decoding asteroid interiors could help aim asteroid-deflecting missions（图）
小行星内部 小行星偏转 自旋变化
2023/6/9
NASA hit a bullseye in late September with DART, the Double Asteroid Redirection Test, which flew a spacecraft straight at the heart of a nearby asteroid. The one-way kamikaze mission smashed into the...
Last week, the stuff of Hollywood blockbusters became a reality when NASA launched its Double Asteroid Redirection Test (DART), a small spacecraft that will smash into an asteroid sometime in Septembe...
Highest-resolution measurements of asteroid surface temperatures ever obtained from Earth
asteroid belt solar system surface temperature
2021/8/9
A close examination of the millimeter-wavelength emissions from the asteroid Psyche, which NASA intends to visit in 2026, has produced the first temperature map of the object, providing new insight in...
Scientists find closest known asteroid to fly by Earth（图）
Scientists closest known asteroid fly by Earth
2020/8/27
On August 16, 2020, the Zwicky Transient Facility, a robotic survey camera located at the Palomar Observatory near San Diego, spotted an asteroid that had, just hours earlier, traveled only 1,830...
Astronomers have obtained observations of the smallest asteroid ever characterized in detail. At 2 meters (6 feet) in diameter, the tiny space rock is small enough to be straddled by a person in a hyp...
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...
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 ...
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...
Collisional evolution and reddening of asteroid surfaces–I. The problem of conflicting time-scales and the role of size-dependent effects
meteorites meteors meteoroids–minor planets asteroids: general
2015/12/25
Space weathering is the generic term used for processes that modify the optical properties of surfaces of atmosphereless rocky bodies under exposure to the space environment. The general agreement abo...
The Asteroid Veritas:An intruder in a family named after it?
Asteroids Asteroids, Composition Collisional physics Impact processes
2015/12/25
The Veritas family is located in the outer main belt and is named after its apparent largest constituent, Asteroid (490) Veritas. The family age has been estimated by two independent studies to be qui...
RUBBLE-PILE RESHAPING REPRODUCES OVERALL ASTEROID SHAPES
methods N-body simulations–minor planets asteroids–planets satellites formation–gravitation
2015/12/25
There have been attempts in the past to fit the observed bulk shapes (axial ratios) of asteroids to theoretical equilibrium figures for fluids, but these attempts have not been successful in many case...
Asteroid rotation and shapes from numerical simulations of gravitational re-accumulation
Asteroids Asteroid formation Asteroid evolution Collisions
2015/12/25
We present simulations of the gravitational collapse of a mono-disperse set of spherical particles for studying shape and spin properties of re-accumulated members of asteroid families. Previous numer...
Size–frequency distributions of fragments from SPH/N-body simulations of asteroid impacts: Comparison with observed asteroid families
Asteroids Collisional physics Impact processes
2015/12/25
We investigate the morphology of size–frequency distributions (SFDs) resulting from impacts into 100-km-diameter parent asteroids, represented by a suite of 161 SPH/N-body simulations conducted to stu...
Insights into collisional physics may be obtained by studying the asteroid belt, where large-scale collisions produced groups of asteroid fragments with similar orbits and spectra known as the asteroi...