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Un velo polvoriento que cubre Betelgeuse durante su Gran Oscurecimiento
M Montargès1,2, E Cannon3, E Lagadec4
1LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, Meudon, France. miguel.montarges@observatoiredeparis.psl.eu.
Nature
|June 17, 2021
Resumen
Las supergigantes rojas pierden masa a través de mecanismos desconocidos. Las Betelgeuse
Área de la Ciencia:
- Astronomía y astrofísica
- Evolución estelar
Sus antecedentes:
- Las supergigantes rojas representan la etapa evolutiva final para las estrellas masivas (835 masas solares).
- Estas estrellas sufren una pérdida de masa significativa, crucial para su evolución y destino de supernova, pero el mecanismo sigue sin estar claro.
- Betelgeuse, una supergigante roja cercana, experimentó un evento de atenuación sin precedentes ('Gran atenuación') desde 2019 2020.
Objetivo del estudio:
- Para investigar la causa del Gran Oscurecimiento de Betelgeuse.
- Para entender los mecanismos de pérdida de masa en las supergigantes rojas.
Principales métodos:
- Observaciones de alta resolución angular de Betelgeuse durante su Gran Oscurecimiento.
- Modelado fotosférico para interpretar las variaciones de brillo observadas.
Principales resultados:
- Se observó que el hemisferio sur de Betelgeuse estaba diez veces más oscuro de lo normal.
- Una masa de polvo, formada por una disminución localizada de la temperatura en la fotosfera, se identifica como la causa.
- Las variaciones de brillo evolucionaron durante semanas, lo que indica cambios rápidos de la fotosfera.
Conclusiones:
- El Gran Oscurecimiento fue causado por un cúmulo de polvo formado debido a cambios fotosféricos.
- La pérdida de masa en las supergigantes rojas es probablemente inhomogénea y está impulsada por procesos dinámicos de la fotosfera.
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