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Glossary term: Actividad estelar

Description: La actividad estelar es un término genérico que engloba los distintos efectos que los campos magnéticos ejercen sobre las estrellas. Las estrellas con campos magnéticos intensos presentan más manchas estelares en su superficie. Además, es probable que los campos magnéticos estelares sean la fuente de calor de la corona de una estrella, por lo que las estrellas con campos magnéticos más intensos emitirán más rayos X y radiación ultravioleta desde su corona. La actividad también puede observarse en el espectro de la estrella, en particular en la emisión de la línea de hidrógeno alfa. En conjunto, estos efectos cuantifican de forma aproximada la «actividad» de una estrella. Las estrellas masivas (de tipo espectral O, B y A temprana) suelen tener una actividad baja. La actividad aumenta entonces en las estrellas de menor masa, alcanzando su máximo en las enanas rojas (enanas M). Las estrellas jóvenes son más activas que las viejas. El Sol sigue un ciclo de actividad de 11 años que da lugar a una variación en el número de manchas solares.

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Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".

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Credit: NASA/SDO/HMI credit link

License: PD Public Domain icons


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Credit: NASA/SDO credit link

License: PD Public Domain icons

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