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Anomalías de isótopos de azufre e hidrógeno en ácidos sulfónicos de meteoritos
G W Cooper1, M H Thiemens, T L Jackson
1SETI Institute and NASA Ames Research Center, MS 239-4, Moffett Field, CA 94035, USA.
Science (New York, N.Y.)
|August 22, 1997
Resumen
Los ácidos sulfónicos orgánicos encontrados en el meteorito Murchison muestran firmas isotópicas únicas. Estos sugieren la formación en ambientes interestelares fríos, posiblemente de los precursores de monosulfuro de carbono.
Área de la Ciencia:
- La astroquímica es astroquímica.
- Geoquímica de isótopos La geoquímica de isótopos es la química de los isótopos.
Sus antecedentes:
- Los meteoritos contienen compuestos orgánicos que proporcionan pistas sobre la química temprana del sistema solar.
- Los isótopos de azufre e hidrógeno en las moléculas orgánicas pueden indicar sus condiciones de formación.
Objetivo del estudio:
- Para investigar la composición isotópica de los ácidos sulfónicos orgánicos del meteorito Murchison.
- Determinar el origen y el entorno de formación de estos compuestos orgánicos extraterrestres.
Principales métodos:
- Análisis de las proporciones intramoleculares de isótopos de carbono, hidrógeno y azufre.
- Medición de las relaciones de isótopos deuterio/hidrógeno (D/H) y azufre-33 (33S).
Principales resultados:
- Se observaron fraccionamientos de isótopos de azufre independientes de la masa y altas relaciones D/H.
- Los enriquecimientos de deuterio sugieren la formación de hidrocarburos en entornos interestelares de baja temperatura.
- Los enriquecimientos de azufre-33 en ácido metanesulfónico indican una posible irradiación ultravioleta de los precursores del disulfuro de carbono.
Conclusiones:
- Los ácidos sulfónicos orgánicos probablemente se formaron en nubes interestelares frías.
- Los precursores pueden incluir moléculas interestelares como el monosulfuro de carbono.
- La irradiación ultravioleta jugó un papel en la vía de formación.
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