相关论文: Regolith behavior under asteroid-level gravity con…
To deflect impact-trajectory of massive km^3 and spinning asteroid by a few terrestrial radius one need a large momentum exchange. The dragging of huge spinning bodies in space by external engine seems difficult or impossible. Our solution…
According to Shoemaker, the "impact of solid bodies is the most fundamental process that has taken place on the terrestrial planets", as they shape the surfaces of all solar system bodies. A lot of information on this process has been…
There is an unceasing incoming flux of extraterrestrial materials reaching the Earth's atmosphere. Some of these objects produce luminous columns when they ablate during the hypersonic encounter with air molecules. A few fireballs occur…
The collision of a spherical grain with a granular bed is commonly parametrized by the splash function, which provides the velocity of the rebounding grain and the velocity distribution and number of ejected grains. Starting from elementary…
Context. Particles in protoplanetary disks go through a number of phases that are dominated by collisions. In each of these events, grains exchange electrical charge via triboelectric effects. This enhances the stability of particle…
Liquid may give strong cohesion properties to a granular medium, and confer a solid-like behavior. We study the erosion of a fixed circular aggregate of wet granular matter subjected to a flow of dry grains inside a half-filled rotating…
Asteroids smaller than about 100 meters are observed to rotate very fast, with periods often much shorter than the critical limit of 2.2 h. Some of these super-fast rotators can also achieve a very large semi-major axis drift induced by the…
We study the role of grain size in the rheological behaviour of calcite aggregates in the semi-brittle regime. We conduct triaxial deformation tests on three rocks, Solnhofen limestone, Carrara marble and Wombeyan marble, with average grain…
Hayabusa2 is the Japanese Asteroid Return Mission and targeted the carbonaceous asteroid Ryugu, conducted by the Japan Aerospace Exploration Agency (JAXA). The goal of this mission was to conduct proximity operations including remote…
Given the compositional diversity of asteroids, and their distribution in space, it is impossible to consider returning samples from each one to establish their origin. However, the velocity and molecular composition of primary minerals,…
Context: The sizes of dust in the interstellar medium follows a distribution where most of the dust mass is in smaller grains. However, the re-distribution from larger grains towards smaller sizes especially by means of rotational…
Evidence is seen for young, fresh surfaces among Near-Earth and Main-Belt asteroids even though space-weathering timescales are shorter than the age of the surfaces. A number of mechanisms have been proposed to refresh asteroid surfaces on…
Small asteroids intersecting Earth's orbit can deliver extraterrestrial rocks to the Earth, called meteorites. This process is accompanied by a luminous phenomena in the atmosphere, called bolides or fireballs. Observations of bolides…
A projectile (84^Kr_36) having kinetic energy around 1 A GeV was used to expose NIKFI BR-2 emulsion target. A total of 700 inelastic events are used in the present studies on projectile fragments. The emission angle of the projectile…
Many asteroids are rubble piles with irregular shapes. While the irregular shapes of large asteroids may be attributed to collisional events, those of small asteroids may result from not only impact events but also rotationally induced…
Carbonaceous chondrites are among the most important meteorite types and have played a vital role in deciphering the origin and evolution of our solar system. They have been linked to low-albedo C-type asteroids, but due to subdued…
The ~200 m/s impact of a single 400-kg Bjurb\"ole L/LL ordinary chondrite meteorite onto sea ice resulted in the catastrophic disruption of the projectile. This resulted in a significant fraction of decimeter-sized fragments that exhibit…
To gain a better understanding of the surfaces of planets and small bodies in the solar system, the flow behavior of granular material for various gravity levels is of utmost interest. We performed a set of reduced-gravity measurements to…
The Stardust mission captured comet Wild 2 particles in aerogel at 6.1 km/sec. We performed high resolution three-dimensional imaging and X-ray fluorescence mapping of whole cometary tracks in aerogel. We present the results of a survey of…
Recent space missions have provided information on the physical and chemical properties of interstellar grains such as the ratio $\beta$ of radiation pressure to gravity acting on the grains in addition to the composition, structure, and…