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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...
How asteroid, comet strikes may have delayed evolution of atmosphere（图）
小行星 彗星撞击 大气科学 高层大气物理学
2023/6/21
Between 2.5 and 4 billion years ago, a time known as the Archean eon, Earth’s weather could often be described as cloudy with a chance of asteroid.
Back then, it was not uncommon for asteroids or com...
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...
Volcanic activity did not play a direct role in the mass extinction event that killed the dinosaurs, according to an international team of researchers. It was all about the impact of an asteroid, the ...
Rocks at asteroid impact site record first day of dinosaur extinction（图）
Rocks asteroid impact site record first day dinosaur extinction
2019/10/18
When the asteroid that wiped out the dinosaurs slammed into the planet, the impact set wildfires, triggered tsunamis and blasted so much sulfur into the atmosphere that it blocked the sun, which cause...
ASTEROID (21) LUTETIA: SEMI-AUTOMATIC IMPACT CRATERS DETECTION AND CLASSIFICATION
Asteroid Lutetia Image processing Patter recognition Crater detection
2018/6/4
The need to develop an automated method, independent of lighting and surface conditions, for the identification and measurement of impact craters, as well as the creation of a reliable and efficient t...
Human activities could change the pace of evolution, similar to what occurred 66 million years ago when a giant asteroid wiped out the dinosaurs, leaving modern birds as their only descendants. That’s...
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...