Video Experimental Relacionado
Updated: Aug 4, 2026
09:44
Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System
Published on: June 5, 2014
Pruebas gravitacionales de una calísto indiferenciada
J D Anderson1, E L Lau, W L Sjogren
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109-8099, USA. john.d.anderson@jpl.nasa.gov
Nature
|May 15, 1997
Resumen
Es probable que Calisto sea una mezcla homogénea de hielo y roca, a diferencia de sus lunas galileanas diferenciadas. Este estado indiferenciado sugiere que Calisto carecía de suficiente calor interno para la separación por composición.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La astronomía es la astronomía.
- La geofísica es la geofísica.
Sus antecedentes:
- Los modelos anteriores de interiores de satélites galileanos incluían estructuras indiferenciadas o en capas.
- Los datos anteriores para Callisto ofrecían información limitada, principalmente su densidad media.
Objetivo del estudio:
- Para determinar la estructura interior de Calisto.
- Para comparar la estructura interna de Calisto con la de otros satélites galileanos (Io, Europa y Ganímedes).
Principales métodos:
- Análisis de las mediciones del campo gravitacional de la nave espacial Galileo.
- Modelado de la composición interna de Calisto basado en datos de densidad y gravedad.
Principales resultados:
- Calisto parece ser un cuerpo homogéneo, no diferenciado.
- Su composición se estima como una mezcla solar de 40% de hielo y 60% de roca (incluyendo hierro y sulfuro de hierro).
- Esto contrasta con los interiores diferenciados de Io y Ganímedes.
Conclusiones:
- El estado indiferenciado de Callisto es consistente con la ausencia de una fase de calentamiento interno significativa.
- La ausencia de calor interno impidió la separación de la roca y el metal del hielo.
- Este hallazgo proporciona nuevos conocimientos sobre la evolución térmica de las lunas galileanas exteriores.
Videos de Conceptos Relacionados
01:27Gravity between Spherical Bodies
Newton's law of gravitation describes the gravitational force between any two point masses. However, for extended spherical objects like the Earth, the Moon, and other planets, the law holds with an assumption that masses of spherical objects are concentrated at their respective centers.
This assumption can be proved easily by showing that the expression for gravitational potential energy between a hollow sphere of mass (M) and a point mass (m) is the same as it would be for a pair of extended...
This assumption can be proved easily by showing that the expression for gravitational potential energy between a hollow sphere of mass (M) and a point mass (m) is the same as it would be for a pair of extended...
01:24Acceleration due to Gravity on Other Planets
The gravitational acceleration of an object near the Earth's surface is called the acceleration due to gravity. It can be measured by conducting simple experiments on Earth. However, such an experiment is impossible to conduct on the surface of other planets.
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
01:10Kepler's First Law of Planetary Motion
In the early 17th century, German astronomer and mathematician Johannes Kepler postulated three laws for the motion of planets in the solar system. He formulated his first two laws based on the observations of his forebears, Nikolaus Copernicus and Tycho Brahe.
Polish astronomer Nikolaus Copernicus put forth a theory that stated a heliocentric model for the solar system. According to this heliocentric theory, all the planets, including Earth, orbit the Sun in circular orbits.
On the other hand,...
Polish astronomer Nikolaus Copernicus put forth a theory that stated a heliocentric model for the solar system. According to this heliocentric theory, all the planets, including Earth, orbit the Sun in circular orbits.
On the other hand,...
01:10Detection of Black Holes
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
01:14Gravitation Between Spherically Symmetric Masses
The gravitational potential energy between two spherically symmetric bodies can be calculated from the masses and the distance between the bodies, assuming that the center of mass is concentrated at the respective centers of the bodies.
01:17The Principle of Superposition and the Gravitational Field
The principle of superposition applies to gravitational forces of objects that are sufficiently far apart. It states that the net gravitational force on a point object is the vector sum of the gravitational forces on it due to various objects. The principle helps calculate the force by listing the individual forces and then vectorially summing them up. However, it should be noted that the principle of superposition is not always apparent. In the presence of a second force, the first force could...