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Gas frío en el viento nuclear de la Vía Láctea
Enrico M Di Teodoro1,2,3, N M McClure-Griffiths4, Felix J Lockman5
1Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, USA. editeodoro@jhu.edu.
Nature
|August 21, 2020
Resumen
Los científicos descubrieron un gas molecular frío y denso que fluye fuera de la Vía Láctea
Área de la Ciencia:
- La astrofísica
- Dinámica Galáctica
- El medio interestelar
Sus antecedentes:
- El Centro Galáctico experimenta procesos de alta energía de Sagitario A* y retroalimentación estelar.
- Estos procesos impulsan un viento galáctico, expulsando materia y energía del disco galáctico.
- El gas de salida observado incluye fases atómicas ionizadas calientes, ionizadas cálidas y frías.
Objetivo del estudio:
- Investigar la presencia y las propiedades de gas molecular frío y denso en el viento galáctico de la Vía Láctea.
- Para entender el origen y el impacto de esta fase de gas no observada previamente.
Principales métodos:
- Observaciones de alta resolución del flujo de salida de gas molecular.
- Análisis de la morfología y cinemática de las nubes de gas frío.
- Asociación con las nubes de hidrógeno atómico en el viento nuclear.
Principales resultados:
- Observación directa de gas molecular frío y denso que fluye desde el centro galáctico.
- Las nubes de gas molecular se están mezclando y potencialmente están siendo interrumpidas por el medio de salida más cálido.
- La masa del flujo molecular es significativa y puede influir en la formación central de estrellas.
Conclusiones:
- El descubrimiento de gas molecular frío en el viento galáctico desafía los modelos existentes.
- Ni la actividad actual de Sagitario A* ni la formación central de estrellas explican completamente la presencia de este gas.
- Este flujo de gas frío podría jugar un papel crucial en la evolución galáctica y la formación de estrellas.
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