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Los aminoácidos de la irradiación ultravioleta del hielo interestelar son análogos
G M Muñoz Caro1, U J Meierhenrich, W A Schutte
1Raymond and Beverly Sackler Laboratory for Astrophysics at Leiden Observatory, PO Box 9513, NL-2300 RA Leiden, The Netherlands.
Nature
|March 29, 2002
Resumen
Los aminoácidos, vitales para la vida, pueden formarse en el hielo interestelar. Esta investigación muestra que los aminoácidos extraterrestres podrían haber sembrado la Tierra primitiva, apoyando la entrega de moléculas prebióticas desde el espacio.
Área de la Ciencia:
- Astrobiología Astrobiología.
- Química orgánica es la química orgánica.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- Los aminoácidos son fundamentales para la vida en la Tierra.
- Las teorías existentes luchan por explicar el origen de los primeros aminoácidos.
- La entrega extraterrestre de compuestos orgánicos es una alternativa propuesta.
Objetivo del estudio:
- Para investigar la formación de aminoácidos en el hielo interestelar.
- Para determinar si las moléculas prebióticas pueden formarse en el espacio.
- Para evaluar la entrega potencial de estas moléculas a la Tierra primitiva.
Principales métodos:
- Análogo de hielo interestelar simulado.
- Irradiación ultravioleta en un alto vacío a bajas temperaturas (12 K).
- Análisis del residuo a temperatura ambiente para el contenido de aminoácidos.
Principales resultados:
- Detección de 16 aminoácidos diferentes en el residuo de hielo irradiado.
- Identificación de la separación enantiomérica en los aminoácidos quirales.
- La superposición entre los aminoácidos detectados y los que se encuentran en los meteoritos.
Conclusiones:
- La formación de aminoácidos es posible dentro del medio interestelar.
- Esto apoya la hipótesis de la entrega de moléculas prebióticas a la Tierra a través de fuentes extraterrestres.
- El polvo cometario, los meteoritos y las partículas de polvo interplanetario son vehículos potenciales de entrega.
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