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Gold Nanostar Synthesis with a Silver Seed Mediated Growth Method
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La evolución morfológica de las galaxias.

R G Abraham1, S van Den Bergh

  • 1Department of Astronomy and Astrophysics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 3H8, Canada. abraham@astro.utoronto.ca

Science (New York, N.Y.)
|August 18, 2001
PubMed
Resumen
Este resumen es generado por máquina.

La apariencia de las galaxias ha evolucionado significativamente a lo largo del tiempo cósmico, con estructuras complejas como brazos espirales cada vez menos comunes en el Universo temprano. Sin embargo, el número de galaxias de disco luminoso se ha mantenido constante desde el corrimiento al rojo 1.

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Área de la Ciencia:

  • La evolución cósmica es la evolución cósmica.
  • La morfología de la galaxia.
  • La astrofísica es la astrofísica.

Sus antecedentes:

  • La apariencia de la galaxia ha cambiado significativamente en el tiempo cósmico.
  • Las galaxias del universo temprano exhiben morfologías distintas en comparación con las galaxias locales.

Objetivo del estudio:

  • Para investigar la evolución de la morfología de las galaxias a lo largo del tiempo cósmico.
  • Para entender cómo las poblaciones de galaxias han cambiado desde el universo temprano.

Principales métodos:

  • Análisis de la morfología de la galaxia en varios desplazamientos al rojo (z).
  • Comparación de las características de galaxias distantes con las clasificaciones de galaxias locales.

Principales resultados:

  • Desviaciones significativas en la morfología de las galaxias observadas en desplazamientos al rojo tan bajos como z = 0.3.3.
  • Los brazos espirales están menos desarrollados y las galaxias espirales con barras parecen más raras más allá de z = 0.5.5.
  • En z = 1, una fracción sustancial de las galaxias son demasiado peculiares para la clasificación tradicional.
  • La densidad espacial de las galaxias de disco luminoso se ha mantenido constante desde que z = 1.

Conclusiones:

  • Las formas familiares de galaxias son relativamente recientes.
  • Mientras que las apariencias individuales de las galaxias evolucionan, la población de galaxias de disco luminoso se ha conservado desde el corrimiento al rojo 1.