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Una escala de masa común para las galaxias satélite de la Vía Láctea
Louis E Strigari1, James S Bullock, Manoj Kaplinghat
1Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, California 92697-4574, USA. lstrigar@uci.edu
Nature
|August 30, 2008
Resumen
Los investigadores estudiaron las débiles galaxias satélite de la Vía Láctea. Estas galaxias tienen una masa común, lo que sugiere que están dominadas por la materia oscura y puede revelar nuevos conocimientos sobre la formación de galaxias y la agrupación de materia oscura.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Cosmología Cosmología.
Sus antecedentes:
- La Vía Láctea alberga al menos veintitrés galaxias satélite conocidas con luminosidades que varían significativamente.
- Descubrimientos recientes del Sloan Digital Sky Survey han identificado numerosas galaxias de baja luminosidad, entre las más débiles del Universo.
Objetivo del estudio:
- Para determinar la masa de las débiles galaxias satélite de la Vía Láctea.
- Para probar modelos de formación de galaxias en pequeñas escalas.
- Para sondear la naturaleza de la materia oscura.
Principales métodos:
- Utilizando nuevas mediciones de velocidades estelares dentro de estas galaxias satélite.
- Analizar la distribución de las estrellas para inferir la masa galáctica.
Principales resultados:
- Las galaxias satélite estudiadas exhiben una masa consistente de aproximadamente 10 ^ 7 masas solares dentro de sus 300 parsecs centrales.
- Estas galaxias son las más dominadas por materia oscura conocidas.
Conclusiones:
- Los hallazgos sugieren una nueva escala potencial en la formación de galaxias.
- Los resultados pueden indicar una escala característica para el agrupamiento de materia oscura.
- Esta investigación proporciona datos cruciales para comprender el contenido de materia oscura del Universo.
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