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Una determinación de la relación HDO/H2O en el cometa C/1995 O1 (Hale-Bopp)
R Meier1, T C Owen, H E Matthews
1University of Hawaii, Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822, USA.
Science (New York, N.Y.)
|February 28, 1998
Resumen
El agua deuterada (HDO) en el cometa Hale-Bopp se midió utilizando el Telescopio James Clerk Maxwell. Su alta relación D/H sugiere que los cometas no son la única fuente de los océanos de la Tierra.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Ciencias planetarias Ciencias planetarias.
- Ciencia de los Cometas Ciencia de los Cometas
Sus antecedentes:
- Los cometas son cuerpos helados que pueden haber suministrado agua a la Tierra primitiva.
- La medición de la relación deuterio-hidrógeno (D/H) en el agua cometaria proporciona información sobre su origen.
Objetivo del estudio:
- Para detectar y cuantificar la relación D/H en el agua del cometa C/1995 O1 (Hale-Bopp).
- Para comparar la relación D/H cometaria con el agua terrestre y los valores protosolares para evaluar la contribución de los cometas a los océanos de la Tierra.
Principales métodos:
- Detección de agua deuterada (HDO) utilizando el Telescopio James Clerk Maxwell.
- Análisis espectroscópico para determinar la relación D/H.
Principales resultados:
- Se detectó con éxito agua desidratada (HDO) en el cometa Hale-Bopp.
- Se determinó que la relación D/H en el agua de Hale-Bopp es (3,3 ± 0,8) x 10−4,4.
- Esta relación es consistente con las mediciones de los cometas P/Halley y C/1996 B2 (Hyakutake).
Conclusiones:
- La relación D/H en el cometa Hale-Bopp es significativamente mayor que la del agua terrestre.
- La relación D/H cometaria es más de 10 veces el valor de H2 protosolar.
- Los cometas por sí solos no pueden explicar el origen de los océanos de la Tierra.
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