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EPOXI en el cometa Hartley 2

Michael F A'Hearn¹, Michael J S Belton, W Alan Delamere

¹Department of Astronomy, University of Maryland, College Park, MD 20742-2421 USA. ma@astro.umd.edu

Science (New York, N.Y.)

|June 18, 2011

Resumen

La misión EPOXI estudió el cometa 103P/Hartley 2, revelando que su actividad es impulsada por la desgasificación de dióxido de carbono. Este proceso expulsa trozos de hielo y muestra una variada composición volátil a través del pequeño núcleo activo.

Área de la Ciencia:

* Ciencias planetarias Ciencias planetarias
* La astronomía es la astronomía.
* Ciencia de los cometas.

Sus antecedentes:

* La comprensión de la actividad cometaria es clave para el estudio del sistema solar temprano.
* Los cometas proporcionan una visión única de los materiales del sistema solar primordial.
* La misión EPOXI apuntó al cometa 103P/Hartley 2 para una observación detallada.

Objetivo del estudio:

* Investigar los impulsores de la actividad cometaria en núcleos pequeños y activos.
* Para analizar la composición y el comportamiento del cometa 103P/Hartley 2.
* Comprender la relación entre las propiedades del núcleo y la desgasificación.

Principales métodos:

* La nave espacial EPOXI realizó un sobrevuelo del cometa 103P/Hartley 2.
* Las imágenes de alta resolución capturaron el núcleo y la actividad del cometa.
* El análisis espectroscópico proporcionó datos sobre la composición volátil del cometa.

Principales resultados:

* El núcleo del cometa 103P/Hartley 2 es inusualmente pequeño pero altamente activo.
* La desgasificación de dióxido de carbono (CO2) es el principal motor de la actividad, a diferencia de los cometas más grandes.
* La sublimación de CO2 expulsa hielo y polvo, creando chorros y actividad.
* Se observaron variaciones significativas en la abundancia volátil en diferentes regiones del núcleo.

Conclusiones:

* Los núcleos cometarios pequeños y activos pueden estar dominados por la desgasificación de CO2.
* Los mecanismos de actividad de los cometas difieren según el tamaño y la composición del núcleo.
* Los hallazgos mejoran nuestra comprensión de la evolución cometaria y las primeras condiciones del sistema solar.

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