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Updated: Jun 9, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
CoRoT revela un ciclo de actividad magnética en una estrella similar al Sol
Rafael A García1, Savita Mathur, David Salabert
1Laboratoire Astrophysique, Instrumentation, et Modélisation, CEA/Direction des Sciences de la Matière-CNRS, Université Paris 7 Diderot, Institut de Recherche sur les Lois Fondamentales de l'Univers/Service d'Astrophysique, Centre de Saclay, 91191 Gif-sur-Yvette, France. Rafael.Garcia@cea.fr
Science (New York, N.Y.)
|August 28, 2010
Resumen
Los investigadores encontraron evidencia de un ciclo de actividad magnética en la estrella HD49933, similar al ciclo de 11 años del Sol. Los datos asterosísmicos revelaron oscilaciones similares a las solares moduladas por este proceso de dinamo estelar.
Área de la Ciencia:
- La astrofísica estelar es la astrofísica estelar.
- Heliofísica es la heliofísica.
- Asteroseismología La Asteroseismología
Sus antecedentes:
- El Sol exhibe un ciclo de actividad magnética de 11 años impulsado por un proceso de dínamo interno.
- Comprender los ciclos magnéticos estelares es crucial para comprender la evolución estelar y la habitabilidad.
Objetivo del estudio:
- Para investigar las firmas de la actividad magnética estelar en la estrella similar al Sol HD49933.3.
- Para analizar los datos fotométricos en busca de evidencia de cambios cíclicos en las oscilaciones estelares.
Principales métodos:
- Se utilizaron datos fotométricos de la misión espacial CoRoT.
- Aplicó análisis asterosísmico para estudiar las oscilaciones similares a las solares en HD49933.3.
- Cambios globales medidos en las frecuencias de oscilación y amplitudes de modo.
Principales resultados:
- Detectó una modulación de al menos 120 días en las oscilaciones de la estrella HD49933.
- Se observó una relación en la que el desplazamiento mínimo de frecuencia correspondía a la amplitud máxima, reflejando el comportamiento solar.
- Identificaron evidencia de un ciclo de actividad magnética bajo la superficie de la estrella.
Conclusiones:
- La estrella HD49933 exhibe un ciclo de actividad magnética, análogo al del Sol.
- Estos hallazgos proporcionan valiosas restricciones para los modelos teóricos de dínamo estelar.
- El estudio demuestra la presencia de dinamos estelares en condiciones distintas a las del Sol.
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