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Actividad estelar y variaciones de brillo: un vistazo a la historia del Sol
Science (New York, N.Y.)
|January 5, 1990
Resumen
El brillo del Sol cambia con su ciclo de actividad magnética, similar a las estrellas más viejas. Las estrellas más jóvenes muestran un comportamiento opuesto, lo que indica un cambio en la variabilidad del brillo solar con el tiempo.
Área de la Ciencia:
- Física solar Física solar es la física de la energía solar.
- La astrofísica estelar es la astrofísica estelar.
- La astronomía es la astronomía.
Sus antecedentes:
- La irradiación solar total (TSI) exhibe variaciones relacionadas con el ciclo de actividad magnética de 11 años del sol.
- Las misiones satelitales anteriores (Misión Máxima Solar, Nimbus 7) proporcionaron datos iniciales sobre la variabilidad de las ETI.
Objetivo del estudio:
- Confirmar y ampliar la relación observada entre la actividad magnética solar y la irradiación solar total.
- Para investigar la variabilidad de brillo estelar en estrellas de diferentes edades y niveles de actividad magnética.
- Comprender la evolución a largo plazo de la variabilidad del brillo solar.
Principales métodos:
- Análisis de las mediciones radiométricas de la Misión Máxima Solar y los satélites Nimbus 7.
- Observaciones estelares realizadas en los observatorios Lowell y Mount Wilson.
- Comparación de los niveles de actividad magnética y los cambios de brillo en el Sol y otras estrellas.
Principales resultados:
- Se confirmó que la irradiación solar total del Sol varía con su ciclo magnético de 11 años.
- Observó que las estrellas más viejas, similares al Sol, generalmente brillan a medida que aumenta su actividad magnética.
- Encontró que las estrellas más jóvenes tienden a volverse más débiles con el aumento de la actividad magnética.
Conclusiones:
- El comportamiento contrastante de brillo de las estrellas jóvenes y viejas sugiere un cambio en los mecanismos físicos subyacentes que gobiernan la variabilidad solar a lo largo de las vidas estelares.
- El comportamiento actual del Sol es representativo de las estrellas más viejas, lo que implica cambios en los procesos de regulación del brillo a lo largo de su evolución.
- Este estudio proporciona información sobre la estabilidad a largo plazo y la evolución de las estrellas, incluido nuestro Sol.
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