Video Experimental Relacionado
Updated: Jun 29, 2026

06:10
Extraction of Structural Extracellular Polymeric Substances from Aerobic Granular Sludge
Published on: September 26, 2016
La naturaleza de los depósitos en estanques en Eros
M S Robinson1, P C Thomas, J Veverka
1Department of Geological Sciences, Northwestern University, 1847 Sheridan Road, Evanston, Illinois, USA. robinson@earth.northwestern.edu
Nature
|September 28, 2001
Resumen
La misión NEAR-Shoemaker reveló el asteroide Eros.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Morfología de la superficie del asteroide Morfología de la superficie del asteroide
- Los procesos de Regolith se llevan a cabo en los procesos de Regolith.
Sus antecedentes:
- La misión NEAR-Shoemaker proporcionó datos sin precedentes sobre el asteroide Eros.
- La superficie de Eros muestra diversas formas de relieve, incluidos extensos escombros fragmentarios.
- Las variaciones en la rugosidad de la superficie van desde campos de roca hasta depósitos excepcionalmente lisos.
Objetivo del estudio:
- Para llevar a cabo el mapeo global y el análisis de color de los depósitos lisos en Eros.
- Investigar los mecanismos de formación y las características de estas características únicas.
- Para comparar los depósitos lisos de Eros con las características conocidas de la superficie lunar y asteroide.
Principales métodos:
- Mapeo de la superficie global de Eros.
- Análisis del color de regiones de superficie distintas.
- Caracterización morfológica y de composición de depósitos lisos.
Principales resultados:
- Los depósitos lisos se concentran en áreas específicas de Eros.
- Es probable que estos depósitos estén formados por material ordenado y más fino del regolito del asteroide.
- Las características exhiben morfologías variadas, todas ellas sugiriendo un origen sedimentario.
- La geografía de los depósitos se alinea con las predicciones de la clasificación fotoeléctrica, aunque los mecanismos siguen sin estar claros.
Conclusiones:
- Los depósitos lisos de Eros representan una nueva clase de características de la superficie de los asteroides.
- La sedimentación y la clasificación potencialmente fotoeléctrica son procesos clave en su formación.
- Estos hallazgos ofrecen nuevos conocimientos sobre la evolución geológica de los pequeños cuerpos celestes.
Videos de Conceptos Relacionados
Density
Density is an important characteristic of substances, crucial in determining whether an object sinks or floats in a fluid. Its SI unit is kg/m3, and its cgs unit is g/cm3. The density of an object helps in identifying its composition, and also reveals information about the phase of the matter and its substructure. The densities of liquids and solids are roughly comparable, consistent with the fact that their atoms are in close contact. However, gases have much lower densities than liquids and...
Density and Archimedes' Principle
When a lump of clay is dropped into water, it sinks. But if the same lump of clay is molded into the shape of a boat, it starts to float. Because of its shape, the clay boat displaces more water than the lump and experiences a greater buoyant force, even though its mass is the same. The same holds true for steel ships. The average density of an object majorly determines if the object will float. If an object's average density is less than that of the surrounding fluid, it will float. The reason...
Porosity and Absorption of Aggregate
Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the aggregate...
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the aggregate...
Deleterious Substances in Aggregate
Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...
Another type of impurity is clay and fine material that...
Abrasion Resistance of Concrete
Abrasion resistance is an essential characteristic of concrete that determines its durability and longevity under various wear conditions. Concrete surfaces are vulnerable to different types of abrasion. For instance, surfaces may wear down due to the constant movement of vehicles or be eroded by solids carried in water, as seen in concrete canal linings. Specific tests are conducted to measure the abrasion resistance of concrete.
One such test is the revolving disc test, where three plates...
One such test is the revolving disc test, where three plates...
Shotcrete
Shotcrete is a specialized technique where mortar or small aggregate concrete rich in cement content is sprayed onto a surface at high velocity. The force of impact compacts the material and enables it to cling to vertical or overhead areas without sagging. The technique involves layering the shotcrete in stages until it reaches approximately 4 inches in thickness. Operator skill in nozzle management is pivotal in deciding the quality of the shotcrete. Shotcrete is used in constructing tunnel...

