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Comet Assay as an Indirect Measure of Systemic Oxidative Stress
Published on: May 22, 2015
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Abundante oxígeno molecular en el coma del cometa 67P/Churyumov-Gerasimenko
A Bieler1,2, K Altwegg2,3, H Balsiger2
1Department of Climate and Space Science and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, Michigan 48109, USA.
Nature
|October 30, 2015
Resumen
El oxígeno molecular (O2) fue detectado en el cometa 67P/Churyumov-Gerasimenko
Área de la Ciencia:
- Ciencia de los cometas
- Astroquímica
- Ciencias planetarias
Sus antecedentes:
- Los comas cometarios están compuestos principalmente de H2O, CO y CO2.
- Otras moléculas como compuestos sulfúricos e hidrocarburos están presentes.
- El oxígeno molecular (O2) se ha detectado en otros cuerpos helados, pero no en los cometas.
Objetivo del estudio:
- Para informar de la detección in situ de oxígeno molecular (O2) en el coma del cometa 67P/Churyumov-Gerasimenko.
- Para cuantificar la abundancia de O2 en relación con H2O.
- Investigar la distribución y el origen del O2 en los núcleos cometarios.
Principales métodos:
- Mediciones in situ de la composición del gas neutro en el coma del cometa 67P/Churyumov-Gerasimenko.
- Análisis de las abundancias de O2 en relación con H2O.
- Evaluación de la isotropía de la relación O2/H2O y la dependencia de la distancia heliocéntrica.
Principales resultados:
- El oxígeno molecular (O2) fue detectado en el coma del cometa 67P/Churyumov-Gerasimenko.
- Las abundancias locales de O2 oscilaron entre el 1% y el 10% en relación con el H2O, con una media de 3,80 ± 0,85%.
- Se encontró que la relación O2/H2O es isotrópica e independiente de la distancia heliocéntrica.
Conclusiones:
- La presencia de O2 sugiere su incorporación primordial en el núcleo del cometa durante la formación.
- Este hallazgo desafía los modelos actuales de formación del Sistema Solar.
- Se necesita más investigación para comprender las condiciones que permiten la incorporación de O2.
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