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Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
Published on: April 24, 2014
Evidencia de moléculas de cadena enriquecidas en carbono, hidrógeno y oxígeno en el cometa Halley
Science (New York, N.Y.)
|August 7, 1987
Resumen
El análisis de iones pesados del cometa Halley reveló moléculas de cadena como el polioximetileno. Estos compuestos ricos en carbono, oxígeno e hidrógeno proporcionan información sobre la composición y los orígenes de los cometas.
Área de la Ciencia:
- Ciencia de los Cometas Ciencia de los Cometas
- La astroquímica es astroquímica.
- Física del espacio Física del espacio
Sus antecedentes:
- Las comas cometarias contienen una compleja mezcla de iones.
- Comprender la composición de los cometas es clave para desentrañar la formación del sistema solar.
Objetivo del estudio:
- Para analizar la composición y distribución espacial de los iones positivos térmicos pesados en el coma del cometa Halley.
- Para identificar las estructuras moleculares presentes en los entornos cometarios.
Principales métodos:
- Mediciones in situ con el analizador de iones pesados RPA2-PICCA a bordo de la nave espacial Giotto.
- Espectrometría de masas para determinar la composición y distribución de iones.
Principales resultados:
- Los picos de masa ordenada observados en 61, 75, 91 y 105 unidades de masa atómica para iones >50 amu.
- Cada pico comprendía múltiples masas muy espaciadas.
- Las abundancias disminuyeron y las tasas de disociación aumentaron con mayor masa.
Conclusiones:
- Los patrones de iones observados sugieren la presencia de moléculas de cadena ricas en carbono, oxígeno y hidrógeno.
- El polioximetileno (formaldehído polimerizado) es una molécula candidata probable.
- Estos hallazgos contribuyen a comprender la complejidad química de los cometas.
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